Flat roof for a private house: is it worth it or not? Mastic as an independent roofing material. Varieties and distinctive features of various types of roofs

To date, a flat roof is not the most obvious solution to the problem of roofing. But in the same Switzerland and Germany, this particular type of roof began to gain more and more popularity. It is possible that in the near future European fashion will come to us.

The following factors contribute to the growing popularity of flat roofs:

• Ease of installation roofing cake. All materials are laid on a flat surface directly under the feet.
• A flat roof has better heat transfer. The roof area is evenly heated throughout the entire sunny day.
• Possibility beneficial use space. Can be done on the roof summer terrace, install a small swimming pool, etc.

But there are also disadvantages:

• A flat roof wears out faster. It will have to be repaired more often, although this does not cause much difficulty.
• A large amount of snow accumulates on a flat roof in winter. First, it creates an extra power load. Secondly, if it is not removed, over time it will begin to melt, and there may be so much water that it, one way or another, will find its way through the roof.
• There is an opinion that a flat roof is cheaper than a pitched one. This is not so, and if you calculate all the costs, which include: floor slabs; deviating screed; insulation that experiences heavy compressive loads, and therefore more expensive than pitched roof; waterproofing; installation of parapets - it becomes clear that a flat roof will cost more.

Traditional or inverted roofing

Before you make a flat roof with your own hands, you need to choose the type of roofing cake. It can be traditional or inverse.

The fundamental difference lies only in the order of laying the elements of a flat roof.

The traditional type involves arranging vapor barrier first, then thermal insulation, and only then waterproofing. This allows you to protect the insulation, but jeopardizes the waterproofing material. The inversion type involves the arrangement of waterproofing, followed by thermal insulation. Thus, the waterproofing material is protected from temperature extremes and excessive pressure.

The device of a flat roof of a private house most often involves the use of the traditional type, and we will consider it in this article.

Foundation preparation

Foundation preparation begins immediately after construction bearing walls. It directly depends on whether the roof will be operated or not. Can be made from:

• Reinforced concrete slabs, subject to the construction of walls of bricks, blocks or concrete panels.
• If the roof is unused, it is allowed to install the base from corrugated board on iron beams. Profiled sheets must have sufficient wave height, type H-153.
• A flat roof in a private house allows the installation of wooden floor slabs on wooden beams. Applicable only on unused roofs small area. They are laid with an interval of two millimeters, which are subsequently compensated for by thermal expansion.
• Possible use wooden planks minimum thickness 40 mm and maximum width 180 mm. They also fit with a small gap. It is applied to the operated roof.

When using wood, do not forget to treat it with antiseptics and flame retardants to increase durability and resistance to fire.

Deceleration device

The next step is the ramp device. Necessary for draining water to gutters.

• By reinforced concrete slabs pour the screed with an approximate slope of 2-5 degrees. This is about 2 centimeters of slope per 1 meter. It is possible that the screed will be preceded by backfilling of expanded clay. Also, the slope can be created using a special wedge-shaped insulation.
• The construction of a flat roof using corrugated board involves the implementation of a ramp at the stage of installation of the base. That is, profiled sheets are initially laid with a slope of 2 centimeters per meter. If this was not done, it was permissible to use a wedge-shaped insulation or to make a slope-forming screed made of polystyrene concrete.
• Wooden slabs are also initially laid with a slope. In its absence, a wedge-shaped insulation is used.

When constructing a roof base made of corrugated board or wooden slabs, the walls of the box are initially made with a slope in the right direction to facilitate the subsequent installation of floor slabs.

Note that the use of a wedge-shaped insulation will cost you more than arranging a ramp with a screed, and even more so than a slope device at the stage of installing floor slabs.

vapor barrier

Vapor barrier is used only in the construction of a traditional type of flat roof. It is necessary to prevent the penetration of vapors from the room to the insulation. For vapor barrier use specialized films. They are laid with an overlap of 10 cm. The joints are carefully glued with adhesive tape. The film is glued no less carefully at the points of junction with various protrusions (parapet, steps, etc.). It is attached to the base with a construction stapler or special galvanized nails.

As a vapor barrier, bitumen-containing materials, such as roofing material, can be used. They are attached to the base with gas burner, joints are glued in the same way. Also, the modern building materials market offers self-adhesive films, the installation of which does not require additional materials.

Please note that the ballast roof does not require mechanical fastening of the vapor barrier to the base.

In turn, a ballast roof is a roof, for the finishing coating of which weighting materials are used - paving slabs or bulk washed gravel.

thermal insulation

Do not forget that before you make a flat roof at home, you need to decide on a slope-forming layer. This will depend on the type of insulation.

The insulation is laid in several layers. To prevent the formation of cold bridges, each subsequent layer must overlap the joints of the lower one. Polyurethane glue is used to glue the layers one to one. In its absence, the use of mounting foam is allowed. Also, all possible holes and cavities are sealed with mounting foam.

Before installing the thermal insulation layer, make sure that there is no moisture on the vapor barrier. The installation itself is best done in parts. That is, lay several squares of thermal insulation, and then immediately waterproofing upstairs. This is necessary so that in case of rain the insulation does not get wet.

Waterproofing

One of the most important steps in building a flat roof with your own hands is waterproofing. Can be made from:

• Bituminous materials, roofing material.
• Bituminous and polymeric materials, euroroofing material.
• PVC films.
• Liquid rubber.

Let's take a closer look at each of the materials.

Roofing material is the simplest, cheapest, but also the most short-lived of all. It is laid on a concrete base, or a heater resistant to high temperatures. Its service life is only 5-10 years. For its installation you will need: a gas burner, a paint knife, a spatula, a brush and a primer for roofing material. The order of work is as follows:

1. Primer treatment.
2. After it has completely dried, the roofing material is rolled out and allowed to lie down for a day.
3. Glue it with mastic. Do not forget to carefully install waterproofing on the ledges.
4. The joints (minimum overlap 7 cm) are processed with a burner.
5. After the first layer, lay the second. The sequence of actions is the same, with the exception of primer treatment. The lower the slope, the more layers, up to four.

Bitumen-polymer waterproofing will last an order of magnitude longer. The order of its installation is as follows:

1. Cleaning the base from dust, dirt and moisture.
2. Primer treatment.
3. Installation of material with a gas burner. If the roofing felt was glued with mastic, then this is not necessary here. The burner heats the entire width of the roll, but it is very important not to melt the material, otherwise it will become too brittle. Especially for this, a pattern is applied to the rolls, as soon as it begins to deform, you can roll it further. The waterproofing takes root to the base with a wooden mop. Minimum overlap 8 mm.
4. In some cases, when installing a flat roof with your own hands, installing the first layer with a burner is difficult. Then use a mechanical fastening in increments of 50 cm.

Due to the need to use highly specialized tools PVC installation membranes and liquid rubber becomes almost impossible without the involvement of specialists. Therefore, it makes no sense to consider these materials in detail. We only note that both types of waterproofing are quite durable.

drainage system

A flat roof in a private house can have several types of drainage systems:

• Interior.
• Outdoor controlled.
• Outdoor uncontrolled.

We will immediately discard the last option, since it is used mainly for outbuildings.

External controlled drainage involves the collection and drainage of water using gutters located on the outside. To drain water, special holes are made in the parapet.

The internal one is mounted directly into the roofing system, even before the roofing cake has been assembled. Due to this, its installation is more complicated, but in this case the drain can be hidden inside the building. In this regard, the issue of water drainage must be resolved before making a flat roof.

It is necessary to determine the design of the roof at the design stage of the building. If you have chosen a flat option, it is very important to represent all the positive and negative aspects of the operation of a building with such a roof. The choice of the type of roof also depends on the use of special materials and technological methods in construction.

Flat roof device

Not always a flat type of roof evoked positive emotions among builders. This was due to some prejudices in the construction and operation of a flat roof - lack of aesthetics, uneconomical, fragility.

Recently, there has been a trend to revive the popularity of flat roof structures, a significant role in this was played by new construction technologies and innovative materials.

A flat roof made of modern materials reliably protects the house and looks beautiful

A flat roofing device can be represented as a multi-tiered "pie" with several layers:

1. Reliable foundation. Most often, this role is played by a reinforced concrete slab or a metal profile structure.
2. Vapor barrier coating. The most popular bitumen or roll materials.
3. Thermal insulation layer. Mineral wool, expanded clay, expanded polystyrene, cement screed - the main components used by builders for thermal insulation.
4. Waterproofing. There are a lot of materials to protect the roof from moisture (bitumen-based mastics, PVC membranes, compositions for liquid fusing, etc.), the choice depends on the material and production capabilities of the developer.

The listed order of layers is not mandatory, in different designs flat roof it can be different.

All elements of the roof must be of high quality, a flaw in at least one of them can lead to problems in the normal operation of the roof.

Pros and cons of a flat roof

A flat roof, despite its apparent simplicity, has a number of useful characteristics attracting builders. Such designs also have disadvantages that must be taken into account.

Advantages of flat roofs

Photo gallery: flat roof operating options

Modern technologies make it possible to plant grass on the roof and arrange a playground exactly like on earth. You can get to such a cafe by elevator. Only a flat roof can be decorated so beautifully and modernly. On the roof, you can place a table, benches, a hammock and enjoy your vacation. Swim in the pool. practically without leaving home - you can only dream about it

Disadvantages of a flat roof structure

No roof is perfect. There are significant disadvantages of a flat roof:

• instability to snowfalls (with heavy snowfall, the likelihood of a roof break increases, with abundant spring thawing, leaks are possible);
• the need to build additional drains for water;
• increased requirements for the state of hydro- and thermal insulation of the roof.

If internal drains are made on the surface of flat structures, then they require constant monitoring of their condition (it is necessary to clean debris, eliminate freezing, etc.).

Types of flat roofs

There are two main types of flat roofs:

The structural differences between the two types of flat roofs are in the order in which the layers are laid. In an unexploited roof, the top layer is waterproofing, which quickly collapses when exposed to various natural factors- sun, wind, precipitation, etc. This option is not suitable for the active use of the roof.

The inversion roof is “packed” differently. The sequence of layers here is: concrete, waterproofing, thermal insulation, protective covering. Last layer often made from drainage or geotextile. Such durable structures are in demand among designers who want to make the most of the entire roof space.

Holding concerts, building car parks, summer cafes and studios implies a high degree of load, so builders lay additional reinforced materials between the insulating layers.

flat roof slope

A flat roof does not have to be absolutely flat, a minimum slope must be provided for. Otherwise, sewage disposal will be difficult, moisture from precipitation will accumulate on the roof and contribute to its rapid destruction.

In the absence of a slope, stagnant zones with negative aspects may appear:

• accumulation of moisture;
• germination of seeds carried by the wind;
• lichen formation.

To prevent this from happening, a slope of one to four degrees should be made on a flat roof. With such a difference in the levels of melt and waste water will not linger on the surface, which will extend the life of the roofing.

Work to create a slope on a flat roof is called slope.

To achieve the desired slope on a flat surface, you can use different materials:

1. Backfill components (expanded clay, perlite, etc.).
2. different layers of insulation.
3. Lightweight concrete mixes different basis(polymers, bulk materials, etc.).

Each of these solutions has its own characteristics in relation to the slope. The use of backfill materials during long-term operation of the roof does not give a clear angle of inclination. Loose materials can slide off the roof, move, which leads to a change in slope. It is difficult to achieve a smooth height difference if using expanded clay large sizes(more than 20 mm).

Accurately leveling an inclined surface with expanded clay is quite difficult.

Lightweight concrete masses are devoid of such disadvantages, but they are quite heavy, not every roof structure provides for such additional weight. These materials cannot be used in cases where the building has already been built and its design is not designed for a large load on the frame and foundation.

Modern industry produces materials that help create the necessary and smooth slope on a flat roof. The polymer base of these mixtures makes them plastic, which is a big plus in construction. flat roofs.

There are other possibilities for creating a slope on a flat roof:

• installation of metal profile structures covered with flat slate;
• construction of a crate (rarely used due to the cost and impossibility of creating small slopes);
• installation of wedge-shaped heat-insulating plates.

The last of these methods is gaining popularity among builders, because this method of ramping has its advantages:

• simple installation. Plates for thermal insulation are already cut at a certain angle. Their installation does not require any special skills, it is enough just to lay the wedge-shaped slabs on a flat surface of a flat roof to get the necessary slope.
• light weight. During construction works You don't have to use any lifts. In addition, the insignificant total mass of insulation boards will not affect the future in any way. performance characteristics roofs.
• Independence from external conditions. Laying wedge-shaped thermal insulation can be done in any weather.

Video: flat roof flattening

Insulation and drainage for flat roofs

To avoid a quick failure of a flat roof, you should take care of its proper insulation and drainage.

Drainage

A drain on a flat roof is mounted outside or inside the building. The choice of water drainage method depends on climatic conditions:

Video: installation of a receiving funnel on a flat roof

Warming

The thermal insulation of a flat roof is carried out differently than the insulation of pitched surfaces.

This process includes two important moments- vapor barrier and thermal insulation. Depending on the type of roof (classical or inversion), the order of the layers changes.

Used as thermal insulation:

• mineral wool;
• Styrofoam;
• polyurethane foam;
• ecological cotton wool;
• foam concrete.

A good vapor barrier can be provided by a polypropylene film and a build-up mass with a bitumen base.

Photo gallery: flat roof insulation

Flat roofs can be insulated in a well-known way - by filling with expanded clay Large surfaces are easier and faster to insulate with mineral wool For the insulation of flat roofs are increasingly used modern materials, for example, extruded polystyrene foam Foam glass provides not only thermal insulation, but also an excellent soundproofing effect Foam concrete is poured automatically using a pump and a flexible hose, so you can handle this work alone

Flat roof ventilation

To begin with, let's denote the negative points that will arise on a flat roof without ventilation. A roof of a flat design, devoid of ventilation, will be “loaded” with condensate. Natural physical processes will lead to the fact that warm air, rising up, will not settle on the elements of the attic (as on a pitched roof), but on a reinforced concrete base. The result of such adverse processes will be the appearance of fungus and mold on the ceiling.

In the future, steam and heat insulation, other roofing elements will suffer. To prevent this from happening, it is necessary to equip deflectors and aerators on the roof. Their installation is provided at the design stage of the building.

Devices to ensure unhindered air circulation are provided at the design stage of the roof

The inflow and outlet of air is carried out due to different pressures outside and inside the building. A flat roof will "breathe" if artificial ventilation devices are placed on it. This will help keep the layers of hydro and thermal insulation from destruction, eliminate the spread of air bubbles and swelling of the roofing material.

Flat roof covering materials

As roofing materials for flat roofs are used:

• mastics;
• polymeric membranes;
• roll materials on a bitumen basis.

They provide good waterproofing and excellent resistance to mechanical stress and temperature extremes.

Bituminous materials

The basis of many roll coatings is oxidized or modified bitumen. Ruberoid, stekloizol, rubemast, euroroofing material - the main varieties bituminous materials applied on a flat roof.

Table: characteristics of rolled bituminous materials

Polymer membranes

These materials have become popular relatively recently. The advantage of such flat roof coatings is plasticity, resistance to damage, resistance to temperature extremes, simple installation. Another big plus polymer coatings- their production footage. The length of one roll of polymer membrane is from 20 to 60 meters, so it can cover large areas of a flat roof very quickly.

Polymeric membranes are available in long rolls, so they can quickly cover large areas.

Operational period of roofs polymer membranes is 30-50 years old.

Mastics

The positive aspects in the use of mastic materials are the absence of seams and the integrity of the coating. The service life of such roofs is from three to ten years.

Applying a viscous and viscous mastic to the roof surface is a simple process, this layer becomes solid at normal air temperature. Mastics are also used as an adhesive base for mounting roll materials.

There are cold and hot mastics. The first type does not require additional manipulations during the preparation and installation, in the second case, the mixture will need to be heated to 180 °. It is safer to work with cold mastics, but hot materials set faster.

Flat roof repair

Any roof needs constant inspection, care and repair. On the roof under the influence various factors cuts, damage, breaks, blisters, delaminations and other problems that interfere with the normal use of the roof can occur. To eliminate such negative conditions, it is necessary to carry out repair work. They can be current, emergency and capital.

Emergency repair is a forced, unplanned measure, emergency measures to restore the integrity of the roof. Current and capital repairs of a flat roof are provided in advance. The volume of work carried out during current and major repairs differs significantly. Overhaul requires more time and costs, while the area of ​​repaired coatings is also much larger.

Defects on roofs covered roll materials, most often eliminated by gluing patches

During emergency and scheduled repairs of a flat roof, patches are most often installed on the damaged area. Materials for repair in each case are selected individually. One of the latest "assistants" when updating a flat roof is a self-adhesive tape with a bituminous coating. It is very convenient and effective to use it for roof repair. There is only one limitation: such a tape is not suitable for repairing damage over a large area.

Flat roof repairs are much easier and safer than pitched roofs. The repair time on such a surface is also much less.

Video: flat roof repair technology

Economic nuances of using a flat roof

If you are wondering about economic benefits, then you should consider some points when building a flat roof.

Of course, the construction of a flat type of roof is less expensive, since the cost of building a rafter system is not required. This will also be the case with operation, if repair of the rafter part of the pitched roof is required. In a flat roof, such an expense item is simply absent.

A pitched roof will require more investment also because it is clearly visible, being an integral part of the facade of the building. The materials used in the construction of the upper layers in a flat roof are not always appropriate for a pitched version. They can be simpler, uncomplicated, while on a pitched roof it is better to use not only reliable, but also beautiful finishes.

The costs of building, maintaining and repairing a flat roof largely depend on its intended purpose. The cost will be much lower if the roof is not in use.

The construction, maintenance and operation of a flat roof have their own natural features. There are advantages and disadvantages to using flat roofs. Given the purpose of using the building, a flat roof should be mounted with strictly defined materials.

The final and one of the most important stages of construction is the construction of the roof. Pitched structures are considered a classic solution, however, in last years there has been a clear trend towards flat roofs. The secret of their popularity lies in the mass of advantages. Previously, flat, or, as they are also called, combined roofs were erected on administrative, civil, medical, and sports buildings. Today, the scope of their application has expanded significantly and includes residential and suburban construction.

Features of a flat roof

The main difference of this type of roofs is the use of sheet and piece materials, forming a solid carpet when laying. These include materials of bitumen and bitumen-polymer type, mastics. To increase resistance to temperature fluctuations and mechanical deformations, such carpets must have increased elasticity. The function of the basis for the carpet is performed by the bearing plates, the surface of the heat-insulating layer and the screeds. Layers stacked one on top of the other form a roofing cake as a result.

Advantages of flat designs

Until quite recently, many people avoided the installation of flat roofs, not being sure of the appropriateness of such a solution. However, in reality, these designs have a number of obvious advantages:

• Flat roofs allow you to get additional usable area that can be used as a recreation area, turn it into a pool, garden, etc.
• An important advantage is the ability to save on material, because with the same architectural basis in terms of area flat cover much smaller than the slope.
• Laying flat roofs is incomparably more convenient than pitched roofs: all materials can be placed side by side and work in a safe position.
• Flat roof maintenance and repair work is greatly simplified.
• Additional area is added without increasing or changing the contours of the structure, which is very important in large cities, where lack of territory and ecology are on the list of the most pressing problems.

Flaws

• One of the disadvantages of flat non-attic roofs is the need to regularly monitor the degree of moisture content of the insulation and maintain the tightness of the waterproofing coating.
• With frequent and heavy snowfalls, a large snow mass accumulates on a flat roof, which increases the load on the structure and often leads to leaks.
• There is a certain risk of blockages in the internal drainage system or its freezing.
• To avoid damage to the roofing, it is necessary to clean the surface from snow accumulations from time to time.

Roof knots

For reliable protection of the roofing pie from external influences, special care must be taken to carry out the areas of its adjoining to such building structures like parapets, walls, pipes, external parts of ventilation systems, etc.

The main nodes of a flat roof are:

• junction node;
• overhang node;
• roof passageway.

The nodes are installed on a reinforced concrete base in those areas where the cut of the roofing pie is adjacent to the vertical structures. Often, manufacturers of roofing materials develop their own systems: each of them may have certain design features.

The main requirement for the nodes is to ensure the tightness of the joint and its thermal protection.

The main components of flat roofs of different types

Exploited and non-exploited roofs

The device of roofs of the exploited type is justified on buildings that provide for the periodic exit of people to the roof or the placement of heavy objects on it.

A design feature of such roofs is the need to create a rigid base or a special screed over the waterproofing layer. Such a measure is necessary to increase the strength of the structure and evenly distribute the load over it. The increased rigidity of the base will preserve the integrity of the waterproofing layer and prevent it from bursting.

A distinctive feature of non-exploited type roofs is the absence of the need to lay a rigid base on top of the waterproofing. AT this case used soft insulation. The creation of this type of roof is advisable when there is no need for maintenance of the structure, since there is no pressure on the roof surface. In cases where there is a need to care for such a roof or carry out certain work, the issue is resolved by installing special transitional bridges or ladders, due to which there is a uniform distribution of pressure over the surface.

By arranging an unexploited roof, you can spend much less money than when installing an exploited one, but it should be noted that it will last much less.

Other types of flat roofs

The design features of flat roofs formed the basis for their division into the following types:

• classic;
• inversion;
• ventilated.

The traditional solution is classic flat design. Otherwise they are called soft.

In the classic version, the base plate functions as a base. On its vapor barrier coating, heat-insulating material is laid - in many cases, slabs based on mineral wool. Since the thermal insulation layer also needs to be protected (in particular, from the effects of precipitation), a waterproofing carpet is arranged, the basis for which are bitumen-containing roll materials.

Structure flat inverted roofs fundamentally different from the classical type: in this case, the insulation layer is above the waterproofing membrane, and not below it. This specificity allows you to protect the waterproofing from the negative effects of ultraviolet rays, from the loss of quality characteristics as a result of freezing and subsequent thawing, with a sharp change temperature regime. This arrangement also prevents mechanical damage to the waterproofing membrane, thereby significantly increasing the duration operational life roofs.

Inversion structures are very convenient to use as operated ones. Plants, grass, light furniture, etc. can be planted on them.

The device of ventilated roofs allows solving the problem of moisture accumulation in the insulation and ceiling slabs, which often causes the formation of bubbles, leading to subsequent leaks and rupture of the roofing carpet. The specificity of the nodes of ventilated flat roofs is the partial fixing of the first layer of the carpet with glue to the roof or laying on mechanical fasteners. This feature allows you to create an air gap between the roof and the base, excluding significant water vapor pressure. Communication with external air is carried out through the junctions along the roof contour or through the installation of special exhaust deflectors.

The base is one of the significant components of flat structures

To obtain a high-quality, functional and durable roof, it is necessary to think in detail about the plan of a flat structure in advance. Such a measure will greatly simplify the installation process itself. In many cases, the main nodes of a flat roof are:

• load-bearing structure - its functions can be performed by a monolith, a ceiling along a profiled sheet or a load-bearing concrete slab;
• thermal insulation layer;
• waterproofing layer;
• slope-forming layer, the function of which is to drain water;

The initial step in creating a flat structure is the preparation of the base. The bearing covering of such a roof in most cases is profiled steel sheets or solid wood-based coverings.

When uneven surface reinforced concrete base requires the creation of a leveling screed from sand-cement mortar or sandy asphalt concrete. The thickness of the screed is determined by the type of base:

• on concrete base– from 10 to 15 mm;
• on rigid insulation boards - from 15 to 25 mm;
• on soft insulation boards - from 25 to 30 mm.

With a roof slope of less than 15%, the screed is first located on the grooves, after which - on the slopes.

With an indicator of more than 15%, the actions must be carried out in the reverse order: first of all, align the slopes, and then proceed to work with valleys and grooves.

All elements protruding above the roofing surface (parapet walls, chimneys, etc.) are treated with plaster to a height of at least 25 cm. Special rails are installed above the plastered surface. Their function is to fix the roll type of the carpet.

To improve the quality of adhesion of the base and the rolled carpet, the roofing screed is primed with mastics for the roof. Before starting work, the surface is thoroughly cleaned.

Soft roofing materials

When installing flat roofs on initial stage it is necessary to prepare all roofing materials for further use.

If rolled materials are used, they are carefully inspected for the presence of different types defects: cracks, bumps, oil stains. After that, they are rolled out and kept in this form or turned inside out for 24 hours.

Roofing mastic performs two functions at the same time:

• It is used as an independent material for providing a seamless coating and for repair work.
• It is used as an adhesive agent for bonding roll-type materials to the base. Bituminous mastics are used both cold and hot.

Mastic as an independent roofing material

The composition of flat structures does not always include rolled materials: they can be arranged using only mastic.

Mastic is essentially a liquid material made from pure elastic hydrophobic polyurethane resins. After being applied to the surface of a flat roof, under the influence of moisture contained in the air, the process of its polymerization begins, as a result of which the material is transformed into a rubber-like continuous membrane with excellent waterproofing and protective properties.

Due to a number of features, mastic is an almost ideal material for flat structures. Its main advantages:

• reliability;
• safety;
• resistance to ultraviolet radiation;
• resistance to precipitation and the development of microorganisms;
• excellent adhesion to building surface any type;
• preservation of the original volume (it does not change even as a result of polymerization);
• ease of use: liquid mastic can be applied manually - using a roller or brush, or a special method of airless spraying.

Roll materials for roofing

An important part of a flat roof is the roofing material itself. The most suitable for flat structures are rolled materials. Their laying is carried out on the surface with an overlap. With a roof slope of more than 5%, the overlap in the inner carpet layers should be 70 mm, in the outer - 100 mm. With a slope of less than 5%, the width of the overlap in all layers is 100 or more millimeters. Rolled strips are laid in a certain (one) direction.

In the case when the panel deviated to the side during gluing, you should try to move it and not peel it off. In the absence of a result or its insufficiency, the glued part is cut off and glued with a 100 mm overlap.

Laying of rolled canvases is carried out in layers. When attaching them to cold mastic, a 12-hour interval must be observed between gluing layers.

Thermal insulation in soft flat roofs

The layer of heat-insulating material can be mounted in two ways: external or internal.

The external (external) method is easier, as a result of which it has become more widespread. In addition, it can be used for thermal insulation of the building both at the construction stage and after its completion, in the operating state.

Depending on the number of layers to be mounted, flat structures provide two types of thermal insulation:

• single layer;
• two-layer.

The choice of a particular type is determined thermotechnical calculation and strength requirements that apply to the roof. When laying on top load-bearing structure thermal insulation boards, the so-called “spread seams” principle is applied.

In the case of a two-layer coating, the joints of the upper and lower slabs also run "in a row". In the areas where heat-insulating plates adjoin walls, lanterns and parapets, transitional heat-insulating bumpers are arranged. Thermal insulation is fixed in the following ways:

• mechanical, in which the fastening of the corrugated board is carried out using self-tapping screws, and the reinforced concrete base - using plastic dowels with a core;
• adhesive;
• with the help of ballast: it can be paving slabs or pebbles;
• on the base.

Horizontal ventilation

During the operation of the roof, damage to the vapor barrier layer can occur, as a result of which moisture enters the insulation, which leads to its freezing in the cold season. All this greatly reduces thermal insulation characteristics material. For this reason great importance has a ventilated roof.

Ventilation of flat structures is a system of aerators (plastic or metal tubes) that are located above the roof membrane. The system emerges on the roof surface in the form of umbrellas protected by nets. They should be located at the highest points of the roof.

drainage system

A very important value in the process of drainage is played by the value roof slope– it should be at least 2%. Even a slight slope prevents the penetration of moisture inside.

In the case of flat structures, the drainage system is of great importance.

Its components are receiving funnels, pipes (through them water flows into the sewer, special storage tanks or into the ground).

Drainage is carried out in two ways:

1. According to the internal system - in this case, fittings (funnels) located on the roof surface collect water flows, after which they are sent to pipes: they are mounted inside the building and are completely isolated from residential premises.
2. By external drainage - pipe fastening is carried out according to outer surface the walls of the house, so that they can be easily cleaned of accumulated dirt.

The disadvantage of the external system is the frequent freezing of pipes in winter.

The specific number of funnels, their diameter, location areas are calculated taking into account the features of the architecture of the building, the operating conditions of the roof and the maximum number atmospheric precipitation in the region. As a rule, funnels are equipped with filters to prevent leaves, small birds, etc. from entering the system.

Materials for the drainage system are polyvinyl chloride or metal funnels. The former are more popular because they do not corrode.

CONCLUSIONS:

• The main difference between flat roofs is the use of sheet and piece materials.
• The structure of a flat roof resembles a multilayer cake.
• Such designs allow you to get additional usable area, which can be used at your discretion.
• The main nodes of a flat roof are: the junction node, the overhang node, the node of the passage through the roof.
• A design feature of operated roofs is the need to create a rigid base or a special screed over the waterproofing layer.
• A distinctive feature of non-exploited type roofs is the absence of the need to lay a rigid base on top of the waterproofing.
• The design features of flat roofs have become the basis for their division into classic, inversion, ventilated.
• The initial step in creating a flat structure is the preparation of the base.
• Flat roofs can be installed using roll materials or only mastic.
• The most suitable roofing for flat structures are roll materials.
• Thermal insulation is laid in one layer or in two layers.
• Ventilation of flat structures is a system of aerators above the roofing membrane.
• Flat roofs can have an internal and external drainage system.

What are the requirements for a flat roof to be covered with rolled materials, you can find out from the video.

This option for arranging the upper part of the building is used, as a rule, in the construction of "high-rise buildings", as well as various administrative, industrial, warehouse and some other buildings: pavilions, showrooms, and the like. Despite the fact that a flat roof has a number of disadvantages, this does not reduce the popularity of such a design, including in private housing construction.

Benefits of flat roofs

Firstly, the installation of a flat roof can be carried out independently, and not to invite assistants or hire professionals, as, for example, when constructing a roof of complex configuration (, four-pitched, etc.). Consequently, their work will not have to be paid (we are not talking about large areas where it will be problematic to cope alone).

Secondly, the construction of such a roof provides significant savings both in terms of materials (money) and in time (the coverage area is much smaller than with pitched equipment). You don’t have to make numerous calculations or order a project (which will cost a lot), assemble a complex system of rafters, install jibs, sprigs, and so on. In addition, there are no restrictions on the choice of the type of roofing.

Thirdly, a flat surface is much easier to maintain and repair, which also gives tangible savings in the future.

Fourth, a choice of arrangement options. A flat roof can either serve only as a traditional "cover" for the house, or be used (inverted). For example, greenhouses, summer gardens, solariums and the like are mounted on it. There are even heliports. This fully compensates for the inconvenience due to the lack of an attic room.

Flaws

• Increased requirements for waterproofing. Since the roof is located horizontally, water falling in the form of precipitation will stagnate on it. You can use eg.
• Debris will constantly accumulate (for example, fallen leaves), so such a roof will have to be serviced more often.
• Lack of an attic (mansard) space

What to consider

• The maximum load that the roof will experience (for roof structure). This includes the weight of the frame itself, roofing material, layers of insulation and insulation, as well as possible snow cover. In addition, you need to rely on the fact that the roof must withstand the weight of people who will subsequently walk on it.
• The purpose of the building and the possibility of further use of the surface (for example, terrace equipment). Depending on this, the type of overlap is determined.

Work technology

The simplest version of a flat roof is when reinforced concrete slabs are laid (for example, a garage, a barn). Everything is extremely simple here. A so-called “layer cake” is arranged on the surface: vapor barrier, if necessary - insulation material, a layer of waterproofing. For the equipment of the latter, roll materials are most often used.

Insulation of a reinforced concrete slab can be done by pouring a layer of expanded clay and equipping a cement screed on top. Slag and some other materials are also used.

Traditionally, roofing material is used for waterproofing, which is covered with bituminous mastics on top. It should be noted that this material will last no more than 5 years, and then you will have to deal with repairs. It is more expedient to lay as a "waterproofer" polymer materials such as membranes. Liquid rubber is also great.

Since the installation of plates requires the involvement special equipment, at independent device flat roof can be equipped with the simplest truss system from wood.

First of all, supports - Mauerlats - are laid on the upper parts of the bearing walls. The most commonly used material is timber. It must be taken into account that these structural elements must be rigidly fixed in order to exclude the possibility of their horizontal displacement.

Therefore, metal pins are immured in their upper end surfaces along the entire length of the walls. Their length is calculated so that after the installation of the Mauerlat they rise above the beam by about 5 cm. Threads must be cut at their ends.

If the masonry is old, then a “tape” of concrete mortar. After that, pre-planned holes are drilled in each wooden blank with a diameter slightly larger than the cross section of the metal "fingers". First, strips of roofing material (or similar waterproofing material), and then Mauerlats. They are mounted on pins, and a washer is put on top of each, and with the help of a nut, the beam is securely fixed at the installation site.

Next, floor beams are laid. It should be noted that the roof should protrude beyond the dimensions of the house by 50 - 60 cm (required overhang). This will protect both the walls and the blind area from water flowing from it, as well as from raindrops.
Support frame device. Depending on the type, it can be either solid (boards, slabs) or cellular (battens).

• Vapor barrier.

• Insulation. For flat roofs there is a nuance. Absence attic space deprives such a building of an “air cushion” from above. Therefore, insulation is carried out both outside and inside. But at the same time, it is necessary to take into account the weight of such material, since it is an additional load on the truss system.

• Waterproofing.

• Roof covering.

• Overhang finishing.

This is only a general list of necessary activities. The technology for the production of work for each item depends on local conditions and on the selected materials.

• Any "wood" used in construction must be well dried. The moisture in its structure gradually “leaves” (natural shrinkage of the material), which leads to a change not only in the volume of the workpiece, but also to its deformation (for example, twisting).
• Wood has two significant drawbacks - it burns and is prone to decay. Therefore, before using it, all wooden parts of the structure are pre-treated with flame retardants and antiseptics. It is better to spend money on these funds than to suffer with frequent repairs later.
• When installing Mauerlats, you need to constantly monitor their horizontalness with the help of building level. Otherwise, the roof will turn out to be skewed. If necessary, either the tape is leveled, or a rigid lining is made under the Mauerlat.
• To exclude stagnant water on the roof, it is advisable to make it with a certain slope (approximately 3 0 - 5 0). As a rule, the decrease goes towards the rear side of the building. To do this, the height of the front Mauerlats increases, so the floor beams will fall with a slope.