Not so long ago, developers were afraid to install flat roofs for their homes. The fact is that the roofing materials produced by factories did not have high waterproofing properties and, as a rule, such a roof began to leak within a few years. Modern Products allow you to create a decent roof for a private house and how this is done is in this article.

Flat designs

Spreading flat roofs began with Western and European countries. Today, it is becoming more and more common throughout Russia. Inflated standards are gradually leaving people's consciousness, and they are opening up to something new. This novelty offers a rather serious alternative, because the construction of a flat structure can significantly save your money, and thanks to high-quality materials, you will receive a roof with a long service life, and it will reliably perform its functions throughout the entire time.

Previously, flat roofs were found only on multi-story buildings and factories, but today any developer can afford this option.

If we look at this roof in detail, it will look like it consists of the following components.

• Base. As a rule, this is a reinforced concrete floor slab, but there are often projects where a metal profile performs this function
• Vapor barrier layer. Various mastics or good roll materials are used here
• Thermal insulation boards. You shouldn't take the layer I wrote literally. To do this, you can use bulk products covered with screed and any other materials that are suitable for this.
• Waterproofing layer. Most developers use roofing felt or other bitumen-based products. Alternatively, a PVC membrane or mastic can be laid

It is worth noting that there are several types of roofing. Depending on it, the position of these layers may change.

Roof slope

Despite its name, a flat roof must have some slope. This allows precipitation to be naturally removed. By removing excess moisture from the surface, you can avoid many destructive processes that try to significantly reduce the life of your roof.

An example is the change in the state of aggregation of water in spring. During the day, the temperature is usually above zero, and the water spreads over the entire plane, and at night it freezes. Moisture, which filled the microcracks of the coating during the day and changed its state of aggregation at night, simply tears the surface of the material. Of course, this is not noticeable at first glance, but in a couple of years you will need repairs.

You can create a ramp in several ways.

1. Use lightweight concrete mix. To create a high-quality ramp, it must include extruded polystyrene. Filling the surface with this mixture will not be difficult and can be done by just one worker. After hardening, the surface will be very strong and durable. It is worth noting that when laying concrete on the roof surface, additional calculations should be made to determine the maximum possible load on the surface. As a rule, this is done at the construction stage of the building.
2. The second option is the same concrete mixture, but mixed with expanded clay or perlite. These two components are bulk materials and they have a small mass. The hardened screed will differ significantly in strength from the previous mixture
3. The greatest preference is given to the third option. Although its creation is a rather labor-intensive process, it can save quite a decent amount and get a durable and durable coating. The whole point is that a layer of bulk product (expanded clay or perlite) is laid on the prepared base, and on top of it a concrete screed. Thanks to the low price of bulk materials, you will win
4. Laying foam concrete blocks and treating them with fiber-reinforced concrete is also a fairly effective method. I note that such a structure will last for more than one decade, but installation work will take a lot of effort and finances
5. The slope can be created without the help of concrete or its alternative. For this purpose, thermal insulation boards are used. They are attached to the base using the gluing method. This will avoid any mixing of the material during operation. Some developers, to be on the safe side, combine glue and dowels for fastening. However, you can do the same if you think it necessary

The operational period of the ramp will depend entirely on the materials used in its creation. The higher their quality, the better.

Sealing joints

The roofing pie should always remain protected from moisture. Dry layers guarantee the performance of its functional task one hundred percent. To achieve maximum sealing, pay special attention to the junction of two planes. For example, bottom vertical wall or chimney pipe. As a rule, flat roofs are equipped with aerators or deflectors to create artificial ventilation. So the places where they connect with the roofing pie should also be treated with sealants.

Types of flat roofing

Before starting construction, it is always worth working out all the nuances. For example, what kind of flat roof to create. In their structure they differ in:

• Traditional
• Inversion

All three options have their own characteristics. Below I will describe each of them in detail, but for now let me explain to you about the loads.

Roofing loads

Most developers equip the roofing surface to suit their needs. This solution is quite effective, for example, if you are a creative person and want a large space for your activities, then move your workshop to the roof. If you don’t create any crafts, then you can just lie on the roof or set up a pool there. Of course, such manipulations will require careful calculations so that the roofing system does not simply collapse.

Unused flat roof

Today, developers are still distrustful of the use of roofs. However, the reason for this may be a lack of funds, but I don’t think this is required large number finance.

The structure of an unused roof has only a few layers, and their installation is affordable for everyone. PVC membranes are very often used for flat roofing. Working with them does not cause any complications and flooring can be done at any time of the year. Even if moisture gets on the insulating boards, thanks to the membrane it will be removed from the roofing pie without any problems. The entire installation process is carried out without any dangerous tools. To connect the canvases into a monolithic surface, heat welding without open flame is used.

It is worth understanding that there are many alternatives for covering flat roofs. For example, bitumen mastic. It is applied immediately over the insulation. This product contains polyurethane water-repellent resins, so the entire surface will be under reliable protection. Liquid mastic soon acquires a surface similar to rubber. It copes with all mechanical damage without problems and reliably performs its functions. As you understand, repairing this surface is not difficult. It is enough just to warm up the mastic and cover the damaged area with it.

Fused surfaces are the most popular coatings for unused roofs. It earned its popularity due to its low cost. This type includes roofing felt. This material is an environmentally friendly material, because it contains ordinary cellulose. The service life of roofing felt is only 10 years, but it can be extended without any problems. To do this, it is necessary to apply new material to the old base. Modern methods production have given rise to new types of surface-surface coatings. Thanks to this, along with the operational period, the waterproofing properties also increased.

Operable roof

Arrangement of a used roof is a much time-consuming undertaking. The price for its creation will depend on what exactly you want to see on it. As a rule, many developers build on the roof of their house small garden or a lawn where you can lie down and take your mind off the hustle and bustle. In European countries you can find unique housing with a swimming pool or a gym on the roof.

According to the building codes that are prescribed in SNiP, it is necessary to take care of safety. However, you probably don’t want to suddenly find yourself on the first floor when you are sunbathing on the roof lawn. An exploited roof has a number of significant differences compared to a non-operated roof. For example, the presence of a screed on top of a waterproofing layer. It will not allow the underlying layers to deform and will protect them from destruction.

So, let's move on to looking at the types of flat roofing.

Traditional flat roof

You should not assume that this flat roof will have any complex structure. The essence of the traditional type is that the layers located under the roofing are laid in the same way as it was originally invented. If you look at the section, you can see the waterproofing located on top of the insulating boards. IN in this case insulation performs two tasks simultaneously. The first is to protect the roofing pie from moisture, and the second is to perform the functions of a covering.

Until recently, this type was the most popular, until they came up with an inversion option, but more on that below. Despite this, traditional roofing has not been forgotten and is still used today. The secret is that new method styling does not allow some materials to fulfill their functional tasks and we have to return to the classics.

Installation of concrete screed on this roofing type It is impossible, therefore, it will not work to equip the roof as an exploitable one. The thermal insulation layer, as a rule, is made not of slabs, but of basalt wool. This material cannot withstand constant loads.

The positive aspects of traditional roofing:

• Fast and simple device
• Small financial costs
• Possibility to lay down the necessary layers yourself

No material or design has exclusively positive properties, so the disadvantage of this type is that roof covering it has to be replaced or repaired more often than usual, because it performs two functions at once, and this significantly reduces its service life.

Flat roof installation technology

A traditional flat roof can be created by two workers; there is nothing difficult about it. It is enough to acquire some tools and study the technology itself.

• First, the base is prepared. Most often a reinforced concrete slab is used, but profiled metal sheets can also be laid
• A vapor barrier layer is laid down. Developers prefer breathable membranes, but in order to save money, you can use polyethylene or polypropylene products. As an alternative, this layer is sometimes occupied by polymer or bitumen roll materials. By the way, they have some advantage, because when fused, a monolithic surface is obtained
• Next on the list for installation is thermal insulation material. It is worth noting that when purchasing this product In the store, ask the seller which insulation is most suitable for a particular building. For example, if you are building a bathhouse, then you will need mineral wool. It has all the characteristics you need, but its price is significantly higher compared to other materials
• Both dowels and special glue can serve as fastenings for thermal insulation. If you used a mechanical fastening method, then you must fasten subsequent layers in exactly the same way. Many workers prefer bitumen adhesive composition. It can only be used if there is a concrete base
• For the bottom layer of waterproofing, the usual material is used - roofing felt or its analogues. The rolls are rolled out over the surface with an overlap of 15-20 centimeters. The fusing work is carried out with gas torches, so it is worth repeating the safety precautions for working with them
• Next, a protective layer of waterproofing is laid. It has sprinkles, which come in several types. The final layer will not allow harm to the underlying material or damage from direct sunlight or aggressive external environment

Now that you know almost everything about a traditional roof, you can start studying the inversion roof.

Inversion roofing

A longer period of operation forces many developers to use this method. It is worth noting that the previous type is far from perfect and such roofs begin to leak after just a few years, although this is not visible from the outside. If we consider the inversion roof from the same side, then it will not leak even after a decade.

Looking at the cross-section of this roof, you can immediately see the differences. The fact is that some layers have changed places here. It is thanks to this trick that inversion roofing wins in everything. In addition to its high performance, it can be installed on an already used building. To do this, simply remove several layers of the old roof and lay the insulation in the right place, and then close the pie in the right order.

Due to the arrangement of layers, an inversion roof can be used. As mentioned earlier, you can equip it with something like a workshop or place a lawn with a garden. These days, landscaping is playing important role in a person's life.

This roof has its own subspecies. Division occurs depending on the magnitude of the load.

• If the roof is subject to minimal pressure, then its structure will include a standard roofing pie: a vapor barrier layer, thermal insulation boards and waterproofing. An example is a summer playground
• In the case of placing more serious weights on the roof plane, it is worth resorting to laying thicker and more durable thermal insulation products. The final covering of such roofs is decorated with paving slabs or other products with identical protective qualities.
• When you plan to organize banquets right on your roof or want to place a swimming pool on it, then these loads are called high. The structure of this subtype will contain reinforcing materials located between the main ones. The roof will be ready after laying the final element - a reinforced concrete slab

Understanding the positive aspects inversion roof, you probably wanted a building with just such a roof.

Creation of an inversion roof

Before starting construction, depending on your needs, you should first decide on future loads, because the entire structure of the future roof will depend on them.

• First, as elsewhere, they begin preparatory work. Starting work requires priming the base with special solutions. This is done for better adhesion of the deposited material to the surface.
• After preparation, a layer of waterproofing material is laid. It is worth noting that the waterproof material is laid first, usually a PVC membrane. At this stage, it is already possible to note a significantly different traditional methods styling
• Laying thermal insulation. For inversion roofs ideal option The material is geotextile. It is laid between the internal insulation and the final covering.
• A variety of products can be used as the outer layer. Selection required material is made based on functional purpose roofs. If you do not plan to place massive equipment on it, then it can be any roll covering. With an average load it is necessary to lay paving slabs and better materials. As for the highest strength indicators, they are achieved by strengthening each layer with geotextiles, and on top of the whole pie is covered with a reinforced concrete slab

It is inadvisable to install an overly complex roof that can withstand enormous loads and then not use it for its intended purpose. Before construction, discuss this issue with your family members or friends.

Breathable roof

Some residents of private houses were not lucky enough to become striking examples neglect of ventilation systems. It was these people, no longer trusting anyone, who began to create breathable roofs. Their structure allows you to easily remove condensate, which is already boring for all residents of Russia. It is formed due to a significant temperature difference, and they are found almost everywhere. As a result, moisture appearing on the roof elements simply destroys it.

In case you didn't know, a small amount of moisture can reduce the performance of insulation boards by more than half. After removing it from these layers, the material will no longer receive its previous properties and will perform its purpose significantly worse. In addition to this, the outer surface of the roof suffers, this is especially noticeable when water evaporates from the surface after rain

A breathable roof can save you from this problem forever and here are its advantages:

• You can create such a roof without dismantling the old flooring. As preparatory work gas burner melt all the old coating
• The layer laid on top will level the entire plane. Thanks to this, precipitation will not linger
• All the money spent on installing a ventilated roof will pay off within a few years

If you decide to install this roof on your building under construction, then you need to understand what the operating principle of ventilation systems is.

The principle of operation of the ventilation system

Surely, you know quite a lot about condensation. It was studied in physics classes at school. Aerators are used to remove excess moisture from the room. If the roof had a certain slope, then the blowing wind could do this on its own, but when we're talking about about a flat roof, then access to the roofing pie is closed. Artificial ventilation, created by aerators and deflectors, does this job.

These devices look like small umbrellas equipped with protective caps. The material for their production is plastic or metal. Aerators operate using the difference in pressure between interior space and outdoor space. Their number is calculated based on considerations. One device should cover 25 square meters of roof.

It does not matter which construction method was used, traditional or inversion, all flat roofs must be equipped with aerators. Otherwise, condensation that appears in the roofing pie will quickly destroy the entire structure and you will need to make expensive repairs.

Minimizing costs and increasing the speed of work completion have long become current trends in the construction industry. The frantic pace of life and production processes forces developers to choose those designs that allow the project to be completed as quickly and cheaply as possible. Therefore, for multi-storey residential buildings of standard construction, industrial facilities, office buildings are increasingly choosing flat roofing based on roll waterproofing materials.

The flat roof, which replaced the intricate designs of gable, triple and hip roofs, is completely utilitarian. Its roofing cake protects the building from moisture penetration and maintains optimal temperature conditions inside.

The technology of using modern rolled roofing materials and installation methods guarantee the highest level of waterproofing and thermal insulation. In this article we will tell you in what conditions and for which structures a flat roof is appropriate.

Performance Features and Benefits

The name “flat” has a figurative meaning, because even though such a flat roofing pie does not have slopes, a slight slope still exists in it. After all, completely flat, even structures will not allow melt water and rain to flow into the designated areas.

Without at least a slight slope of 2-3 degrees, excess moisture accumulates on the roof, forms puddles, and causes leaks. Unlike other varieties, the technology for installing a flat roof made of rolled materials has the following advantages:

• Economical. Comparing the construction costs of even the simplest gable structure and a flat one, it is obvious that the pitched options are inferior in terms of saving material resources. On this cost item, you can save up to half the money included in the estimate for the construction of the roof thanks to the use of inexpensive rolled materials.
• Speed ​​and ease of installation. Due to the lack of need for rafter system, work on laying flat roofs is carried out very quickly, despite their significant area requiring overlapping. In addition, the workers performing the installation may not be highly qualified.
• High degree of protection from wind and precipitation. This point is especially important for the construction of high-rise buildings. Imagine a skyscraper with gable roof, the picture that pops up in your imagination will surely cause laughter. But, without taking into account the appearance of such a roof, its installation is impossible due to unsafety. The higher the structures being overlapped, the stronger the wind load, the more flat their roof should be.
• Efficient use of space. The flat multi-layer pie of the roof in use makes it possible to compensate for the entire area occupied by the building. Since on it you can arrange a parking lot, a swimming pool, a recreation area, a cafe, even a garden, or install solar panels. At a time when living space is scarce in megacities, every square meter of available space must be used as efficiently as possible.

Flat roof installation

The structure in the form of layers of rolled materials is called a roofing pie. This pie consists of three types of layers:

1. Base. Depending on the method of using the roof, this role is played by either concrete slabs or sheets of profiled metal. The main purpose of this layer is to give rigidity to the structure. Since one of the features of a flat roof is that it can be used not only for temporary occupancy of people, but even for parking cars or arranging a swimming pool.
2. Screed. Its task is to set the slope of the roof surface so that melting and rainwater were canalized in . To do this, use a concrete mixture or cement-sand mortar. It is recommended to lay a slope of 2-3 degrees in roofs under construction, and 1 degree in those being restored or repaired.
3. Waterproofing. A layer that prevents moisture from penetrating into the roofing pie. For its production, bitumen, polymer and bitumen-polymer roll materials are used.

Important! The nature of use makes adjustments to the structure of the roofing pie, adding special layers, but the base, screed and roll waterproofing materials are present in any type of flat roof.

Types by nature of use

The design of a flat roof varies significantly depending on how it will be used. The following types are distinguished:

Simple exploitable roof

Roofing pie of an exploited flat roof

If the building design involves the installation of a serviceable flat roof, a drawing is drawn up showing the sequence of layers of the pie. They are usually arranged in the following order:

1. Reinforced concrete base;
2. Concrete slope screed;
3. Waterproofing film or membrane in the form roll material;
4. Drainage metal grate;
5. Thermal insulation material;
6. Sand-cement mortar;
7. Terrace covering.

Extruded polystyrene foam or mineral wool in the form of solid slabs is used as thermal insulation. Most often, used flat roofs are covered with paving slabs intended for paths and parking lots.

The main disadvantage of this method of arrangement is that the insulation is located quite close to the surface, which is why it can deform, sag, get wet, and therefore loses more than 50% of its peat-insulating properties.

Inversion exploitable roofing

Before the invention of membrane elastic materials, builders noted significant drawback– rapid wear of the waterproofing layer, which was made from rolled bitumen derivatives based on cardboard.

Since it was located at the top of the cake, its condition quickly deteriorates due to exposure to temperature changes, UV rays, mechanical damage. The way out of this situation was the invention of an inversion flat roof, the arrangement of layers of which is different.

It looks like someone turned the roof pie upside down. Waterproofing from roll materials, bitumen or bitumen-polymer material is laid on concrete slabs.

This is followed by a layer of moisture-resistant insulation; extruded polystyrene foam covered with geotextile is ideal. The top layer required for protection is made by pouring gravel. This technology and placement of roll materials has three advantages:

• The waterproofing layer of the roof, securely hidden in the thickness of the roofing pie, lasts longer, as it is not exposed to external influences.
• Condensation does not form on the insulation located in the upper part of the roof, it does not get wet, and retains high thermal insulation qualities 20-25 years.
• The thermal insulation layer is close to the surface of the slabs, making it easy to replace them and repair the roof.

Green roof

This type of exploitable roof turns the top of the building into a blooming oasis, with lawns, flower beds or small beds with kitchen herbs and vegetables. In conditions of high gas pollution in cities, green roof not only decoration, but a means of their healing and relaxation.

The peculiarity of this type of roof is that on top of the insulation, a layer of geotextile is laid to retain the soil layer and the soil itself, which is subsequently sown with a grass lawn mixture. It is important to choose high-quality, reliable waterproofing and moisture-resistant insulation, for example, polystyrene foam.

Ventilated roof

The invention of a ventilated roof solves the problem of moisture accumulation in the thickness of the roofing pie. It penetrates there in various ways: it settles in the form of condensation on the insulation, accumulates in the concrete screed, and remains in the layers of the old roof. A breathable roof gives excess water an outlet - aerators, installed at the rate of 1 piece per 50 square meters. m.

Ventilated roof

Advantages of ventilated roofs:

1. Installation does not require removal of the previous roof covering.
2. Aerators guarantee effective evaporation of moisture, and a new layer of screed effectively channels it through the drainage system.
3. A method that can be used both during repairs and during the initial installation of the roof

Flat roofs different types opens up many opportunities for implementing bold design projects. This is the future of housing construction, modern technology for the careful use of free space, because the arrangement of greenhouses, gardens on the roofs, and the placement of solar panels will make the life of city residents more convenient and comfortable.

Video instructions

Recently, flat roofing has been increasingly used in private construction. This design allows you to significantly increase the area that is available for use. This type of roof, which has a relatively small slope, can be used not only in the construction of residential buildings, but also to cover garages and terraces.

This type of roofing is used not only in the construction of residential buildings, but also to cover garages and terraces.

A flat roof section is shown in Fig. 1.

All design details are durable. During the installation of this roof, you will need to insulate it, otherwise, when the cold base of the roof covering comes into contact with the warm air emanating from the room, condensation will appear, which will appear in spots on the ceiling. Moisture will accumulate on the roof, destroying the structure.

Items that will be needed:

• cement;
• crushed stone;
• sand;
• water;
• reinforcing bars;
• vibrator or tamper;
• vapor barrier material;
• waterproofing;
• roofing felt;
• slats;
• plumb line;
• roulette;
• building level.

Specifics of constructing such a roof

Figure 1. Sectional view of a flat roof structure.

Flat roofs can be divided into the following types:

1. Soft. Such a roof consists of a load-bearing slab on which thermal insulation material is laid on top of the vapor barrier layer. The latter is often found in the form of sheets mineral wool. Thermal insulation material is protected from precipitation using a waterproofing carpet, which will be based on materials in rolls.
2. Inversion. The structures are an improved version of soft roofs.
3. Operated, the base of which must be rigid. This will preserve the integrity of the waterproofing material. As a base, you can use a concrete screed that can provide the slope necessary for water drainage. Another option is to use profiled sheets. The layer of insulation material on such roofs will experience high loads, so you should choose a material with increased strength.
4. Unexploited. For these structures, the rigidity of the base for installing insulation does not matter. Access to the roof for repair work is carried out by erecting bridges and ladders that distribute the loads evenly over the base. Such roofs are budget-friendly, but they are less durable when compared with existing structures.

It is worth noting that an insignificant slope can significantly reduce the roof area. This makes it possible to reduce material costs and reduce volume necessary work on the roof. Heating costs can also be reduced since there is a smaller heat transfer area.

A flat roof has the following disadvantages:

1. Any error in the material selection process may result in renovation work DIY flat roof you will need ahead of schedule, as a result, the overall service life of the structure will be reduced.
2. During snowfalls, the roof may leak.

Figure 2. Membrane installation diagram for flat roof construction.

To make the design reliable, you will first need to draw up a project and select quality material for covering.

Soft flat roofs consist of a base on top of which a vapor barrier material is laid that can protect the insulation from moisture. In this case, you need to take into account the following nuances:

1. The vapor barrier can be made in the form of a bitumen membrane, which is reinforced with fiberglass. Another option is to use a vapor barrier film that is laid on top of the screed.
2. In the outer parts of a flat roof, you need to install a vapor barrier material with your own hands so that its height is greater than the height of the insulation. After this, the seams will need to be soldered.
3. Insulation is laid on top of the vapor barrier material.
4. A carpet is placed on top of the insulating material, which is constructed from bitumen-based materials.

In the case of constructing a roof, the design of which does not provide for loads, waterproofing material should be glued along the perimeter of the roof.

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How to make ventilation?

It is worth knowing that a violation of the tightness of the waterproofing layer can lead to moisture entering the insulation material.

IN winter period Over time, freezing water will increase in volume, tearing the waterproofing away from the surface. Due to temperature changes, cracks will appear, which often lead to roof leaks.

To eliminate such problems, you will need to build a “breathing” roof. To do this, you need to install aerators, which are devices made of steel tubes with caps.

Aerators must be placed evenly throughout the structure. The devices will use the pressure difference created by air flows to remove excess water vapor from the base under the roof. This is done to prevent the roof covering from delaminating.

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How to make waterproofing?

Waterproofing of such a roof is in most cases carried out using bituminous materials, which during the installation process will need to be fused together with a gas burner. To make a flat roof with your own hands, you may need self-adhesive materials.

It is worth noting that such materials have low threshold service life. Therefore, if they are used, it will be necessary to carry out repair work and re-cover the roof every few years.

Today in most cases they are used synthetic materials which have the following advantages:

• increased strength;
• fire resistance;
• resistance to aggressive environments and sun rays.

Membrane installation schemes may be different. One of the device options is shown in Fig. 2.

Such membranes are attached to the roof screed and lie freely on the surface. Another option is installation in a complex manner, which involves the use of an adhesive mixture.

Mechanical fixation is carried out by rolling the material over the flooring, fastening its sheets together and fixing it over the entire area of ​​the structure. In this case, shrinkage will not damage the building.

In case of heavy rainfall, sometimes flooding of the structure occurs. To eliminate this, you will need to build a drainage system. This design consists of external and internal devices.

In the process of installing internal drainage, the roof base must be divided into zones so that there is 150-200 m² per riser. If there is a smaller area, then you will need to make another riser. At the slope points of the roof base, special funnels must be placed and equipped with elements for collecting debris.

In most cases, funnels are placed in the central part of a flat roof with your own hands, and drainpipes are installed inside the building. To prevent water from freezing, it is necessary to arrange around the funnel cable heating area 1 m².

Recently, there has been a clear trend towards installing flat roofs. They persistently displace the usual gable structures, giving the exterior of the building a more stylish and laconic look. The installation technology and flat blood device have their own characteristics. In this article we will tell you in detail how to make a flat roof with your own hands or choose the best option for your home.

If earlier projects of flat-roof houses were common only in the West and Europe, today more and more Russians prefer this option. Gradually, the standards of classical construction are becoming a thing of the past, and people are choosing more practical and economical technologies. This is exactly what a flat roof is. Its structure is such that installation requires much less financial and time costs compared to a gable roof.

Typically, flat roof designs can be found on country houses or rich cottages, but implementing such an idea is not such an expensive undertaking.

A flat roof consists of several layers:

• base (reinforced concrete slab, metal profile structure);
• vapor barrier (bitumen or roll materials);
• thermal insulation (mineral wool or polystyrene foam boards, expanded clay, cement screed);
• waterproofing (bitumen-based roll materials, PVC membranes or various mastics).

Depending on the type of roof (more on this below) and design features, the order of the layers may vary. The insulation and waterproofing method are selected depending on the base used.

Roof slope

During the construction of a flat roof, it is imperative to ensure its slope from 1 to 4 degrees. Thus, it will be possible to avoid the accumulation of rain and melt water on the surface, thereby reducing the risk of corrosion, leaks, and damage to roofing materials.

The outer covering of the roof will very quickly become unusable if the accumulated water freezes and thaws on it repeatedly. To organize the slope of the roof, materials are selected depending on technical characteristics designs.

The most popular material for this purpose is a lightweight concrete mixture containing extruded polystyrene. It is quite easy to lay it, even without professional skills, and the hardened material has exceptional strength and durability. However, the use of this mixture should be taken into account at the building design stage, since concrete will place a strong load on load-bearing elements and floors.

An alternative option is a concrete mixture with expanded clay or perlite. It costs much less than polystyrene, but has more weight, so the roofing cake will be less durable.

The slope can also be organized using monolithic thermal insulation. To do this, lay sheet insulation on a surface prepared in advance and fix it with glue to prevent the slightest movement over time. It is recommended to use not only glue, but to “fix” the effect with dowels with plastic spacers in order to prevent contact of metal elements with the base of the roof (potential places for the appearance of cold bridges).

The most difficult way to create roof slopes is to use bulk materials, since pouring concrete into a layer of expanded clay, for example, will be quite difficult, taking into account the fact that a certain angle of inclination must be maintained. However, the result is a very strong and durable coating.

Another effective way The leveling consists of laying foam concrete blocks and covering them with fiber-reinforced concrete. Such thermal insulation of the pie will last for decades without major repairs, however, the cost of materials and the specifics of installation will require significant financial expenses.

Roofing units

For quality protection roofing pie from destructive influences environment special attention should be paid to the points where it connects to walls, pipes, ventilation and other building elements. The main task of the catch is to ensure the tightness of the joints and their thermal insulation.

The units are organized on a reinforced concrete base in the places where the cut of the roofing pie adjoins vertical structures. For many large manufacturers There are our own systems for creating nodes that take into account the design features of materials.

Types of flat roofing

Before you decide to install a flat roof, you need to choose the most suitable option. There are several types of flat roofs depending on the functional load or design features. So, in the first case, roofs can be used or not.

According to the design features of the roof there are:

• traditional;
• inversion;
• breathable;
• green.

A flat roof allows you to use the roof space as an additional usable area, which is actively used in residential and industrial construction. On such a roof you can make a garden, an open area for relaxation, games, or even build a swimming pool or a parking lot. In order to build a durable and strong roof, you should understand the types of functional organization and select the appropriate elements of the roofing pie.

Unused flat roof

The unexploited type is the most common. If you look at a cross-section of such a roof, you can clearly see that it consists of several layers, each of which is responsible for the load-bearing capacity of the structure. Distinctive Features non-exploitable roofs are low construction costs and relatively simple installation.

To build a practical and inexpensive roof, today they mainly use PVC membranes, since they can be worked with in almost any weather conditions. Even if the thermal insulation layer absorbs moisture during installation, the membrane will quickly remove it. Installation of membranes into a monolithic sheet is carried out using welding equipment without open flame.

An unused roof can be covered and bitumen mastic, applied evenly over the thermal insulation. It is made on the basis of polyurethane water-repellent resins. After application, the mastic quickly polymerizes and forms a cast rubber-like coating that is resistant to moisture and mechanical damage.

The most popular way to organize this type of roof is built-up waterproofing. This is an inexpensive technology that provides long-lasting moisture protection for 20 years or longer. Bitumen-polymer coating is produced in the form of rolls, which are rolled out on the roof and secured by heating with open-flame welding equipment. The same method is used for the construction of exploitable roofs.

Operable roof

The construction of a serviceable roof will require much greater financial and time costs, but as a result you will receive additional usable space.

Today, exploited roofs are becoming increasingly popular, especially in densely populated cities. They can be used to build restaurants, parking lots, parks and sports grounds, saving space on the ground.

SNiP requires that this type of roof can withstand uneven heavy loads and not deform over the entire area. If you look at such a roof in cross-section, you can find a number of significant differences from the unused type. The main one is the presence of a special rigid screed over waterproofing layer. It eliminates deformation (punching) protective coating and its subsequent destruction.

Traditional roofing

Traditional roofs are structures in which waterproofing is located on top of a thermal insulation layer, being at the same time a finishing coating in contact with the external environment. This is the most common type and can be seen on almost every modern flat roof structure. And if previously roofing felt was used for waterproofing, today PVC membranes are the best option.

Important: Traditional roofing cannot be used because it is not equipped with a reinforcing concrete screed. In the process of arranging a traditional roof, it is used basalt wool, which cannot withstand constant loads.

Advantages of the traditional type of roof:

• simplicity and high speed installation;
• low cost;
• the opportunity to make a flat roof with your own hands.

One of the disadvantages is the fact that the waterproofing coating must be completely replaced or repaired from time to time.

Roof installation

The technology for creating a traditional flat roof is quite simple, so even an inexperienced craftsman or a hardworking owner who wants to save on hiring a work team can handle it.

How the installation works:

1. Prepare the foundation - lay floor slabs or organize a monolithic foundation from a reinforced concrete slab.
2. Lay a vapor barrier - for this it is recommended to use film polyethylene or polypropylene materials, bitumen or polymer roll materials. The latest fused products have advantages over film products - they are denser and thicker, and when fused, no seams are formed through which moisture can penetrate.
3. Lay thermal insulation - the thermal insulation material should be selected taking into account the climate and functional features buildings. For example, for a bathhouse it is better to lay several layers of material to better retain heat inside. The most popular material for this purpose is mineral wool. It has all the necessary characteristics and is inexpensive.
4. Thermal insulation material can be fixed mechanically or by adhesive. In the first case, telescopic dowels are used, in the second, bitumen adhesive is used. The method of fastening the thermal insulation determines the method of subsequent fixation of the waterproofing. If you used dowels, then the waterproofing should be fixed with them, and vice versa. Experts recommend using bitumen for fastening only when it comes to installation on a concrete base. If you use a polymer-bitumen vapor barrier, it is better to secure everything with dowels.
5. Lay the bottom layer of waterproofing - to do this, roll the material over the surface and attach the strips with an overlap of 15-20 cm, after which they are welded using a fire or non-fire method.
6. Lay the top layer of waterproofing - the second layer increases the reliability and durability of the roofing pie. To do this, the rolled material is fused over the entire area of ​​the roll, and not just along the edges, as is the case with the bottom layer.

Inversion roofing

Recently, conscientious owners prefer to install inversion roofs because of their durability and better reliability compared to traditional ones. While conventional roofs begin to leak after a few years, inverted roofs remain intact for decades.

If you look at the structure in cross-section, the difference from a traditional roof lies mostly in the change in the order of the layers. It is this factor that determines high quality pirogue. Moreover, such a roof can be built on an already constructed building. To do this, you just need to dismantle the top layers and then lay out the insulation in the required sequence.

An inversion roof, unlike a traditional one, can be used. It can be used to organize various corporate meetings, create a convenient summer studio for fresh air, playground or hold a banquet.

There are several types of inversion roofs depending on the degree of load:

1. Minimum loads - the design consists of steam, heat and waterproofing, as well as a lightweight finishing coating made of rolled material. It can be used in private homes as a summer area.
2. Medium loads (above household level) - thicker and more durable ones are used thermal insulation materials, finishing coat is a paving slab or other material with similar characteristics.
3. High loads - on such a roof you can build restaurants, car parks, hold concerts, etc. Intermediate reinforced materials are installed between the main insulating layers; the outer covering is a reinforced concrete slab.

Installation of inversion roofing

Depending on the expected load, the method of installing the inversion roof is selected. Let's consider the general aspects of arranging this type of roof.

Installation stages of inversion roofing:

Breathable roof

The formation of condensation between the insulating layers of the roof has always been a problem, especially for residents of Russia, where changes in temperature and humidity are observed annually. Condensation is formed due to a strong difference in temperature between the outside and inside of the building. Accumulating in a porous or soft thermal insulation layer, it quickly reduces the protective characteristics of the roof. As a result, smudges, cracks, bubbles and other unsightly formations appear on the ceiling inside the house.

The outer covering of the roof also suffers, especially in the summer, when accumulated moisture is actively evaporating. Lack of ventilation ultimately leads to the roof covering simply peeling off from the base.

The so-called breathable or ventilated roof allows you to get rid of this problem forever. Through special holes, moisture evaporates freely from the internal insulating layers. Roof aerators are installed on the surface, placing 1 piece each. approximately 40-50 sq. m.

Advantages of a “breathable” roof:

1. There is no need to dismantle the already installed flooring for installation. The usual old coating is fused by welding, thereby enhancing the waterproof properties.
2. The second layer of waterproofing, fused over the old coating, levels the surface and ensures high-quality moisture outflow, since it is laid with a slight slope.
3. Certain financial costs for organizing a roof ventilation system are fully recouped within several years.

The principle of operation of the ventilation system

Condensation can completely damage a building within a few years, so it is important to organize the correct and careful installation of the ventilation system. Roof aerators are special fans attached to pipes of various lengths and diameters made of plastic or metal. The fans are covered with umbrella-like caps on top to prevent moisture from entering them from outside.

The aerator operates due to the pressure difference between the outside and the inside. Warm air currents, coming from below, collide with the cold air of the street, thereby driving the fans. Thus, the moisture is independently “blown out” from the roofing pie.

On ordinary flat roofs with a simple configuration, ventilation openings are located evenly across the entire surface at the highest points and at the junction of thermal insulation elements (mineral wool boards). Ideally, installation of ventilation should be carried out during the process of laying the roofing pie, otherwise the costs of its installation will increase.

Interesting fact: Western builders actively use natural smoke removal systems when organizing “breathable” roofs. They allow you to safely leave the building during a fire.

Green roof

We left the most for last interesting way flat roof devices. A green roof is an original way to acquire your own “piece of nature” in the middle of an urban area. This separate trend in landscape design and architecture has already gained popularity in the East and West, where people living in megacities experience an acute lack of green spaces. Gradually, the trends of greening roofs are becoming popular in local latitudes.

Advantages of green roofs:

• saving space - on the roof you can make a place to relax among the greenery, a golf course, grow useful crops (spices, berries, some vegetables);
• the ability to create the most comfortable relaxation area;
• an additional source of pure oxygen in the city;
• plants absorb nitrates and toxins floating in polluted city air;
• the fertile soil layer on the roof cools interior space buildings in summer and protects from cold in winter;
• ensuring almost 100% sound insulation of the room.

Important: When arranging such a roof, it should be taken into account that even a very thin layer of soil creates a noticeable load on the roof, so it is recommended to strengthen the structure or calculate the maximum permissible load.

There are two types of green roofing:

The impressive thickness of the fertile layer dictates certain requirements to the degree of rigidity and reliability of the foundation. Load-bearing structures must withstand not only the weight of the earth, but also the weight of plants planted in it, furniture installed in the improvised garden and people who will relax there. To this should be added the weight of water, which can make the soil heavier during rains.

Green roof installation

The technology for installing a green roof is, by and large, no different from the construction of a conventional flat roof with increased load. A layer of waterproofing is laid on top of the reinforced concrete base, and extruded polystyrene foam is poured on top, which serves as reliable protection from the cold. Next, a layer of geotextile is placed and drainage is carried out, covering the surface with crushed stone or gravel. Then they cover it with another layer of geotextile, fill it with soil and begin planting plants.

Important: special attention should be paid to the drainage system. To do this, it is necessary to arrange the roof at a slope so that water can flow down freely. If there is no slope, then such a drainage system must be created artificially. Otherwise, the water will stagnate, which will lead to waterlogging of the soil and damage to the roofing pie.

If you organize a green roof system correctly, you can create a full-fledged garden or vegetable garden right in the middle of an urban area. We invite you to take a look at the options for arranging a green flat roof (photo):

Green roofs not only allow you to better arrange your own leisure time, but also improve the atmospheric environment in a densely populated city. For example, in Japan, for this purpose, all available free areas are specially covered with grass and trees. They also actively use the technique of vertical cultivation of various crops, turning concrete facades into fantastically beautiful houses.

If you also want to contribute to the restoration of the Earth's ozone layer, green roofing is your option.

Flat roofs, their types and designs can be classified:

• According to the purpose of the surface. Can be exploited or unexploited.
• According to the method of laying the roofing pie. It can be traditional and inversion.
• By type of construction. It can be attic or non-attic.
• Ventilated and non-ventilated structures are distinguished separately.

Operable roof

A usable flat roof can be used as a parking lot, helipad, tennis court, swimming pool, green roof or just a terrace. In any case, it is necessary to calculate the possible load on the roof.

• Load from operation (weight of a person, car, water in a swimming pool, etc.).

In some cases, the roof is subjected to a pressure of 20 tons per square meter.

Also, due to the design of a flat roof, it is highly susceptible to ultraviolet rays.

Together, these factors mean that the choice building materials For such a roof you need to approach it with special care.

The structure of the roofing pie of the roof in use is as follows:

• Reinforced concrete floor slab.
• Sloping layer. Made from slag, concrete, expanded clay, wedge-shaped mineral insulation and other similar materials. The top is secured with a concrete screed. Slope angle up to 3%. Necessary for high-quality drainage of water in the required direction. Sloping is always installed in front of the waterproofing to ensure water flow through it.
• Leveling concrete screed.
• Waterproofing. Made from bitumen, polymer, PVC materials and sealants. Roofing felt is often used, laid in two layers, and it is important that the joints of the upper and lower rows do not coincide.
• Thermal insulation. Keeps the room warm in winter and cool in summer. Requires a careful approach to calculating thickness. In case of an error, condensation may form inside the room. If not an inversion type of roofing is used, but a traditional one, the insulation must be resistant to steam. If on the contrary, there must be resistance to water absorption.
• Drainage layer. Given the flat roof technology, water should flow along the surface into drainage trays. But in other cases, moisture can get into the joints between tiles used as finishing paving elements, or be absorbed into the ground when using a green roof. To prevent the elements of the roofing pie from getting wet, a drainage layer is installed that drains water in the right direction.
• Then everything depends on the type of roof being used. If it is a green roof, geotextiles are laid, which will prevent plant roots from destroying the roofing pie. If it is a roof terrace, or a parking lot, behind the drainage layer there is a concrete screed under the tiles or other finishing material.

Please note that when using traditional roofing, the order of the elements of the roofing pie changes. A vapor barrier is laid over the slope-forming layer, then insulation, and only then waterproofing.

The advantages and disadvantages of this method are discussed below.

Unused roof

An unused flat roof is distinguished by its efficiency. It is not designed to withstand any loads other than snow. This allows for a less careful approach to the selection of building materials.

The structure of a roofing pie of this type of roof is as follows:

• Reinforced concrete floor slab. Instead, it is allowed to use profiled sheets with a high wave height, such as N-153 and N-158.
• Slope formation layer.
• Vapor barrier.
• Thermal insulation.
• Waterproofing.
• Ballast layer of gravel. The thickness of such a layer should be from 10 to 20 centimeters. Necessary to protect waterproofing from exposure to ultraviolet rays and prevent fires.

Once again, we draw your attention to the fact that the layers of steam, heat and waterproofing can change places depending on the type of roof used.

Traditional roof

The traditional type of flat roofing has been used for a very long time. In this case, the roofing pie will look like this:

• Slope formation layer.
• Vapor barrier. Necessary to protect the insulation from steam emanating from the room. Otherwise, even in the case of one percent moistening of the thermal insulation layer, a significant increase in thermal conductivity occurs. Made from specialized vapor barrier membranes and films.
• Thermal insulation. Almost all types of insulation can be used, even with a low percentage of moisture resistance.
• Next, according to the traditional roofing drawing of a flat roof, a layer of waterproofing should be laid. Please note that it must be of high quality, since it is absolutely not protected from temperature changes.

The advantages of a traditional roof are that it guarantees protection of the thermal insulation layer from getting wet. Firstly, this allows you to use the entire range of roof insulation materials. Secondly, the insulation will not lose its thermal conductivity characteristics, which means that a comfortable temperature regime will always be maintained in the room.

At the same time, this flat roof design compromises waterproofing. It is maximally susceptible to temperature changes, which leads to its accelerated aging. Also, the insulation does not protect the waterproofing from external force loads, which again negatively affects its service life. In general, this type of roofing is less durable and requires fairly frequent repair work.

Inversion roof

It is a more progressive type of flat roof device. It assumes the installation of the following roofing pie:

• Reinforced concrete floor slab or corrugated sheet.
• Slope formation layer.
• Leveling concrete screed.
• Primer for waterproofing, for better adhesion. During this process, the screed is carefully inspected for cracks and water bubbles. The cracks are covered with solution, water bubbles are removed.
• Waterproofing.
• Thermal insulation.
• Next is either a drainage or ballast layer, depending on whether the roof will be used or not.

Inversion roofing has the following advantages:

• Protection waterproofing film from temperature changes. As a result, this extends the service life of the film in particular, and the service life of the roof in general.
• The insulation redistributes force loads across the waterproofing in such a way that this does not affect it.
• Extruded polystyrene foam, which is usually used as thermal insulation for this type of roofing, is cheaper than mineral wool used for traditional roofing.
• The inversion design of a flat roof allows for more repairs, if it is necessary to replace or add insulation.

There are also disadvantages, which include:

• It is permissible to use insulation materials only with closed cells to prevent them from getting excessively wet.
• The need to install more complex design gutters.

Attic roof

The technology for installing a flat roof with an attic implies the possibility of using two types:

1. The attic roof is a lightweight superstructure, and attic floor acts as the main supporting structure.
2. The attic floor and the attic roof are independent of each other and are able to withstand power loads equally well.

The advantages of a roof with an attic are:

• Possibility of constant monitoring of the tightness of the waterproofing layer.
• The ability to regularly monitor the condition of the insulation.
• The insulation can be laid after the roof has been installed.
• The attic itself performs the functions of thermal insulation.

Disadvantages include:

• Impossibility mechanical cleaning from snow, provided that the attic roof is used as a light superstructure. Instead, the attic is blown with hot, dry air, which ensures that the snow from above melts and gradually melts away.
• This type of roof is more expensive.

Roofless roof

More popular is the roofless roof. She:

• It costs less than an attic.
• Easier to install.
• Provides snow melting by conducting heat from the room.

A roofless flat roof also has a significant disadvantage:

• There is no way to timely detect a violation of the waterproofing layer. This damage appears as a wet spot on the ceiling, making it impossible to determine the exact location of the leak.

Ventilated and non-ventilated roof

Roof ventilation is arranged between the insulation and the waterproofing layer. Thus, constant air circulation is achieved, which ensures constant dryness of the insulation. Used with the traditional type of roofing pie.

When installing ventilation, it is important to adhere to the following recommendations:

• Height vent at least 1/30 of the width of the building.
• Hole diameter not less than 1/150 total area roofs.
• Air inlets should be lower than the outlets.
• The holes are evenly distributed across the width of the entire building.

In turn, non-ventilated roofing does not require the creation of additional roof elements for flat roofs. But this somewhat shortens the service life of the thermal insulation material.