Houses with a flat roof projects. Flat roof for a private house: a general overview of construction technology

For many, flat roofing is associated with urban multi-storey buildings, faceless and monotonous. But we are ready to surprise you! A flat roof in a private house will be a pleasant discovery for you if there is not much snow in your area, but the winds are quite strong. The fact is that in winter all snow accumulations from such a roof will simply be blown away. And the main thing is that not a single strong hurricane can tear off a roof that simply does not exist! And a whole ocean of possibilities opens up before you, which you can now build above your head: a cafe, a dance floor, a mini-garden and even a whole greenhouse!

The main thing is to know about all the intricacies of arranging houses with flat roof, and everything will work out. And now we will reveal all the secrets.

Such a roof is much smaller in area than the most gently sloping roof. And this means savings on materials.
Such a roof is built much faster than a gable roof, and even more so a hip roof.
Comfort and safety of all rafter work. You still have to manage to fall from such a roof!
Convenient subsequent repairs and replacement roofing covering.
Unlike two pitched roof, dismantling the old flat covering is usually not necessary - this is additional waterproofing and protection. The new pie is made directly from the old one, which saves a lot of time and effort.
The ability to use the roof as an additional useful area where you can plant a flower garden, make an open terrace and even build a greenhouse.
The ability to install transparent roof elements (with careful waterproofing), and thus create a view of the night sky.
Possibility to build a house with a laconic architectural form. Minimalism is at the peak of fashion!

And now – about the pros and cons:

Such a roof generously accumulates snow. After all, he now has nowhere to slide, and the snow itself often becomes the cause of leaks.
On especially generous days, the snow will have to be removed mechanically, which often damages the roofing.
The structure of the roof becomes more complicated: now we need gutters, which also become clogged.
The difference is that water drains from a pitched roof quite quickly (and sometimes it does get into the under-roof space). But it actually stands on a flat surface!
Monitoring the moisture content of the insulation and the general condition of the roof should be regular.
But, despite the fact that for its arrangement building materials you need much less than for a pitched roof; a flat roof is much more complex in terms of installation. Let's just say that there are many more different subtleties and nuances that are important to know about.

That is why many have fair doubts about the reliability of such a roof. But the European and overseas experience of private residential buildings with a flat roof is successful, and therefore you can safely get down to business.

Just consider these points:

There is much more snow in Russia than in warmer European countries.
The only thing worse than snow is the large difference between summer and winter temperatures, which not all foreign roofing materials are designed for.

And here technology decides everything!

What is a flat roof?

So, what acts as the load-bearing base of a flat roof:

Reinforced concrete slab.
Roofing sandwich panels.
Reinforced steel corrugated sheet.

And thanks to the fact that they learned to make a flat roof “breathable”, i.e. with internal ventilation, it has now become possible to use completely non-breathable waterproofing - roofing felt similar to it.

Any roof that we call flat actually still has a slight slope: to one side or specifically towards the drainpipe.

Here is the simplest example of a flat roof for a private home:

Types of flat roofing: non-exploitable and inverted

Of course, unused roofs are cheaper. And the exploited ones, which are correctly called “inversion”, include additional materials.

A separate type of flat roof of a residential building is exploitable. Those. the one on which people will walk and what objects will stand. This is the same garden, or sports ground, or summer cafe. All this creates considerable loads on the roof, and therefore its design is already different from that which is intended only to protect the house from precipitation.

So, the main difference in the design of traditional and inversion roofing is that in the first, the thermal insulation layer is located under the waterproofing, which is quite logical, and in the second, it is above it. But in the second option, the waterproofing is more protected from ultraviolet rays and temperature changes. This design is more durable and functional: you can safely lay out a lawn or lay paving slabs on it.

And now in more detail.

Unused roof: standard pie

But a person can also occasionally climb onto an unused roof - for the same repairs, for example.

Those. in a traditional flat roof, the top layer is waterproofing, and it is this that is exposed to all mechanical and temperature loads.

A separate type of it is a roof with a pressure layer, which is designed so that a person can walk on it from time to time:

Inversion roofing: reverse pie

The standard slope of an inversion roof is 5-7%. The inversion method assumes that the thermal insulation layer is already placed on top of the waterproofing, which now also serves as a vapor barrier.

Moreover, the pie of inversion flat roofs can be very different. It all depends on what you are going to arrange on the roof: a terrace, a mini-pool (and this is not uncommon) or a garden. But the base will still be common: a monolithic screed is made, which levels the entire surface, then waterproofing is laid and the whole thing is covered with insulation. And on top is a cement-sand mixture or rubber coating.

Note that active use of the roof means frequent damage to the insulating layer, which is why moisture makes its way to the insulation and freezes in winter. Over time, the entire roofing pie deteriorates, and therefore without ventilation system A flat roof is indispensable.

A cement-sand screed can even better distribute the pressure layer on the heat insulator, but it must be additionally reinforced with a mesh to prevent cracking.

Subtleties of flat roof insulation

A layer of thermal insulation for a flat roof is mandatory. For comparison: gable roof insulated only when equipment is installed underneath residential attic, and in all other cases the maximum is laid mineral wool on the attic floor. But for a flat roof, insulation is always necessary.

The fact is that without a heat-insulating layer in a flat roof, condensation will constantly appear on the ceiling in the house (such a roof will turn out to be the cold part on which water vapor will rush). And this is bad not only because repairs will have to be made, but also because the entire structure deteriorates.

You can insulate a flat roof both from the outside and from the inside - the difference is small. What is more important is how many layers of insulation a particular roof needs – one or two.

Thermal insulation materials need to be attached to the base of the roof mechanically, both screws or dowels, and glue. Sometimes the fastening is not used at all if the heat insulator is located from the outside and there is pressure on it paving slabs or pebbles.

Why two layers? The fact is that the first layer of thermal insulation on a flat roof acts as insulation; it is from 70 to 200 mm thick. And the second, from 40 to 50 mm, is designed to distribute all the loads. And it is important to calculate the thickness of both layers accurately, based on climatic features terrain and the future use of the roof itself.

With double-layer insulation, all joints should be spaced apart, in a checkerboard pattern, so as not to overlap each other. Moreover, in the places where the slabs adjoin the walls and parapet, it is additionally necessary to make heat-insulating sides. A cement-sand screed can even better distribute the pressure layer on the heat insulator, but it must be additionally reinforced with a mesh to prevent cracking.

Proper drainage system

But this is already a difficult task. Flat roofs are just bad because they are completely open to rain. But everything can be solved! The main thing is to properly organize the drainage, and for convenience, we have explained this issue for you in the following schematic illustrations:

Internal ventilation device

Another important point when installing flat roofs - ventilation. The fact is that if moisture accidentally gets into the insulation, it no longer evaporates - it only accumulates. As a result, the heat-insulating material rots and the waterproofing swells. And there are many reasons for leaks: damaged waterproofing, mechanical damage to the top layer of the roof, cracks and damage from frozen water.

A wet thermal insulator is also bad because it causes bubbles and cracks to appear on a flat roof in the summer heat - all due to the active evaporation of water. As a result, the roof covering also collapses. And if moisture gets under the old screed over time, then the entire roof begins to peel off. This is why a flat roof must “breathe”.

For this purpose, so-called aerators are used. They look like simple plastic or metal pipes, covered with umbrella caps. They should be located evenly over the entire roof area, preferably at its highest points. The essence of this mechanism is that different pressures are created inside the roof and the air begins to create currents, simultaneously taking with it all the excess moisture vapor.

In practice it looks like this:

In addition, in any living space, water vapor rises up to the ceiling. Moreover, they often successfully overcome this barrier (the water molecule is very small) and end up in the insulation, which is bad for it. This is why vapor barrier is required. And not the kind that is usually used for attic insulation, but a dense one, made of high-quality polypropylene or polyethylene. The bitumen membrane is even more reliable.

Choosing a suitable roofing covering

So, what is used as a coating for such roofs?

Option #1 – bitumen and polymer-bitumen materials

Such roofs are the least expensive for owners of private houses. We are mainly talking about roofing felt and euroroofing felt. These are rolled roofing sheets, the base of which is synthetic fabric, and the sides are bitumen. As an elastic and frost-resistant material, bitumen serves as excellent protection and waterproofing.

Moreover, laying bitumen roofing on a flat roof is absolutely simple, you only need gas-burner. The rolls are easily fused together.

But such a roof has significant drawback– fragility. And another thing is that roofing felt does not breathe at all, i.e. It is vapor-tight, and therefore it is necessary to arrange ventilation for such a roof, unless you want the insulation to rot within a year:

Option #2 – liquid rubber

Such roofs have the great advantage that they do not contain any seams. As we have already said, the disadvantage of a flat roof is, first of all, that snow accumulates on it, which then causes leaks.

But there are some subtleties here. So, you need to take only two-component liquid rubber for a flat roof, preferably the highest quality one. And it is extremely important to apply this material correctly to a flat roof: evenly, avoiding unnecessary layers and savings in certain places. So, where the paint was applied unevenly, problems can be expected within 8-10 years.

Option #3 – PVC, TPO and EPDM membranes

Roofing membranes are valuable as a covering for flat roofs because they allow steam to escape. After all, no matter what kind of vapor barrier is used, moisture still, at least a little, gets into the insulation, not only from below, but also from above - after heavy rains, for example.

There are three types of membranes for installing such a roof: TPO, PVC and EPDM. The most popular is PVC membrane, which is also the most flammable. An EPDM membrane is more durable and affordable, but if mechanical damage occurs in it, nothing can be done to fix it, whereas a PVC membrane can only be melted with a hairdryer. In addition, the joints EPDM membranes you need to glue it with a special tape, which is much less reliable than soldering PVC sheets.

But the cheapest membrane in its sector is PVC. But it has such significant disadvantages as low resistance to ultraviolet rays and fear of contact with bitumen, various oils and even polystyrene foam, otherwise the service life will be significantly reduced.

Gluing EPDM membranes requires professional skills. TPO membrane, like PVC, is also welded with hot air. The best is not afraid of ultraviolet radiation, is more chemically resistant and can be laid directly on polystyrene foam or an old bitumen roof without geotextiles. But its service life is shorter than that of EPDM, so for installing a flat roof on a residential private house, we recommend using a PVC membrane.

So, a flat roof device with a PVC membrane is traditionally made like this:

Step 1. We arrange a monolithic floor slab.
Step 2. Place a tear-resistant vapor barrier film.
Step 3. We make a bend from insulation or screed.
Step 4. Place insulation. In private construction this is usually 35 density foam, and on top is 50 mm XPS, which is even stronger.
Step 5. Now geotextiles, 300-500 g per square meter.
Step 6. Let's move on to waterproofing - this is a PVC membrane. The insulation density is enough to allow walking on such a roof. But, if you plan to make an open terrace on the roof, then you need to continue the pie further.
Step 7. Lay the geotextile again - now directly on the membrane.
We lay rubber tiles or reinforced screed 5-7 cm, on which we already lay paving slabs. To make a screed, you need ballast.

And such roofs are made of rubber, polymers or even foil. Unlike bitumen, they are durable, fire-resistant and adhere firmly to the base. A slight slope is achieved using expanded clay concrete or concrete screed.

How to achieve 100% waterproofing?

The main task when installing a flat roof is to make all joints and junctions as airtight as possible. After all, such a roof is most affected by moisture, hail, temperature changes and wind-blown debris. Therefore, the sealants used to seal such joints must be of high quality and resistant to any influences. This is also a kind of expense that has to be incurred.

For the same purpose of waterproofing, it is recommended to make the slope of a flat roof at least 2%. Few? In fact, this is quite enough so that all atmospheric moisture does not linger on the surface, but flows down into funnels and pipes, and from them into the septic tank, soil or sewerage system. Therefore, even at the design stage, you need to carefully think through the future drainage system.

Moreover, the drainage system itself is made both internal and external. Thus, the internal drainage system consists of fittings - funnels located throughout the roof that receive the flowing water and direct it into pipes that go through the buildings, but are isolated from the living quarters. The only disadvantage of such a system is that the pipes become clogged with small debris and leaves, for which it is advisable to equip them with special filters and periodically clean them.

External drainage systems are already attached to the outer walls of the building. These are, of course, easier to clean when they become clogged, but in cold weather they often freeze over. For this reason, it is customary to additionally supply them with electrical heating in the form of cables.

As for the material for the internal and external drainage system of a flat roof, PVC or metal is quite suitable. Both options have their pros and cons. Thus, polyvinyl chloride does not corrode, but is more brittle than metal.

To prevent gutters from freezing in winter, equip them with roofing thermal cables.

Green area on the roof: fashionable and environmentally friendly

Greenery and recreation areas are often lacking not only for residents of the “concrete jungle”, but even for owners of private houses. The whole point is that the same beautiful garden furniture It’s not always possible to leave it in the yard of the house, and beautiful rare flowers in the garden flower bed are often trampled by pets. Therefore, it is not surprising that the green area on the roof has become fashionable among cottage owners. Especially if the access to it comes directly from the bedroom and no one else can disturb your morning peace with a cup of coffee.

There has also become a fashion for some cafes to make the roof flat and put a small greenhouse on it. All the greens go straight to the table! And it’s profitable, because it’s not so easy to bring fresh dill or onions to the kitchen, and it’s economically profitable - there’s somewhere to send kitchen waste. And it is difficult to understand who borrowed this idea from whom: enterprising residents of private houses with a flat roof, or the best minds in public catering. But the fact that such an arrangement of closed ground is beneficial is a fact: rodents will not dig under the beds, insects and pests will not reach (as well as pests in the form of neighbors), and the fact that it is always a little hotter on the roof is only a plus for the same tomatoes. But the main thing is to correctly calculate the loads on such a roof during construction!

And the roofing pie is often standard: waterproofing for the ceiling, thermal insulation, geotextiles, drainage and geotextiles again. And on top you can use both soil and beds:

Or in this version for more powerful floors:

A flat roof is a huge scope for any imagination. Designers and architects love to bring to life a variety of projects for her: a garden, a greenhouse, a jogging track, a mini-beach with sun loungers, and much more. Some craftsmen even manage to make a parking lot on it!

Flat-roofed houses represent one of the most original and impressive manifestations of modern architecture. Thanks to such a roof, the building acquires not only an unusual appearance, but also additional space, ideal as a place to relax or receive guests. Projects of houses and cottages with a flat roof have high level practicality, which is determined not only by saving space. Thanks to its bold lines and right angles, the roof structure blends perfectly with the surrounding landscape, making it even more beautiful.

Flat roof house

When constructing such houses, various technologies can be used (monolithic, frame-monolithic or frame). By using such methods, you can get truly strong, high-quality housing. Many developers, in most cases, give preference to materials such as wood, concrete, as well as wooden or metal profiles, due to which the finished house structures have high levels of stability and lightness. The technology for constructing houses with this type of roof makes it possible to equip open balconies of impressive size or large panoramic windows, which is why they are becoming increasingly popular.

In our country country houses with a flat roof have not yet earned such popularity as in the West, and are, at most, a kind of indicator of a certain status. Initially, talk about arranging a flat roof came only in cases where high-rise buildings were erected. apartment buildings. But recently the situation has changed a little - roofs are allocated for recreation areas, and sun loungers, swimming pools and barbecue ovens on the roof are no longer surprising.

A flat roof can be an excellent relaxation area

Flat roof projects are conventionally divided into several types: conventional, inversion, exploitable and non-operational. The operating option is characterized by the greatest difficulties during installation, since such a roof must have high levels of tightness obtained due to high rigidity.

Flat roofs of private houses, due to the special configuration of their base, have a solid slope-forming surface made over the ceiling. A profile sheet can serve as a rigid base, and materials with high compressive strength can be used for insulation. If desired, you can also use soft insulation, but in such a situation you will definitely need a covering screed. Remember that the strength and reliability of the roof structure itself depends on the rigidity of the base and insulation.

Scheme of a flat roof of a house

When settling in unused roofs There are no special requirements for the rigidity of the insulation. To be able to move on the roof, it is necessary to install special ladders that will carefully distribute the existing load.

Features of building a house with a flat roof

Simple flat roofs are structures consisting of several structural and technological layers:

The base of the roof with a layer of membrane (acting as a vapor barrier). Thanks to this, the insulation is reliably protected from the effects of moisture that forms in the interior of the house. Includes a reinforced (via fiberglass) bitumen-polymer film or vapor barrier, which is located on top of the screed.
Insulation and waterproofing carpet. This roofing roll carpet consists of a material based on bitumen. Expanded polystyrene often acts as insulation. They spend on it cement screed with further laying of a two-layer waterproofing carpet.

What to consider when choosing a flat roof house design

When choosing a house project with a flat roof, do not forget that such a roof needs timely and high-quality care. Some developers are wary of constructing such roofs, as they believe that precipitation may accumulate on its surface, which will subsequently fall into the interior of the building. At the same time, there is an opinion among people about the high cost of maintaining this type of roof and the high costs of building materials.

It cannot be said that houses with a flat roof are so common in our area. Still, we are more accustomed to seeing classic gable or multi-slope roofs. It is believed that houses with a flat roof look exclusive, even eccentric, and speak of their owner as a great original, a modern person who thinks outside the box.

By and large, “flat roof” is a rather arbitrary name. There should always be a small but obligatory slope. Otherwise, rainwater or water after melting snow will accumulate on the roof, which will ultimately lead to serious troubles and costs for repairing not only the roof, but also the interior.

In addition to its direct functions - thermal insulation and protection of the house from precipitation - a flat roof can be used as an additional recreational area.

Let’s try to figure out how appropriate it is to choose a house design with a flat roof in our area. To do this, you need to imagine the advantages and disadvantages of this type of roof.

Advantages of a flat roof

A flat roof allows you to optimize costs. It is smaller in area than any pitched roof. This allows the developer to save significant amounts on materials.
The simple shape of the roof significantly reduces installation time.
For the same reasons, repairing and maintaining the flat roof of an already constructed building is incomparably simpler than in houses with pitched roofs.
But the most important advantage of house designs with a flat roof is the additional usable space that the home owners can use at their discretion. Some elements can be placed on the roof of such a house engineering systems, for example, ventilation and air conditioning systems. Can you install solar panels.
But most often the flat roof space is used as an additional area comfortable rest. Here you can equip a solarium or a place for sports. By the way, there are even projects that make it possible to equip a swimming pool. The roof garden looks very impressive. Modern technologies allow you to pave the roof with paving stones. And in combination with a lawn and decorative trees, comfortable wicker furniture, garden gazebo with a fireplace, this place will become the center of a family holiday.

Naturally, like any roofing system, a flat roof has its disadvantages

More careful design and installation of the roof will be required, otherwise retribution in the form of expensive interior repairs is inevitable.
You will also have to pay additional costs for organizing internal drains.
There are certain inconveniences associated with maintaining a flat roof. Firstly, constant monitoring of the moisture content of the insulation and the tightness of the roof is necessary. Secondly, there is always the possibility of clogged or frozen internal drains. Thirdly, in snowy winters there is a risk of leaks due to large accumulations of snow. But this disadvantage can be easily circumvented if you install an Anti-Ice system on the roof. True, this leads to additional costs.

Project of a house with a flat roof: is it worth doing?

We can say quite definitely that with careful design study and competent work of builders, it is worth building a house with a flat roof. Ultimately, you get original housing with additional square meters useful area and save money on construction work and materials. And the Dom4M company hopes that you will live in comfort for many years comfortable home, built according to our design.

Non-professionals associate a flat roof with the negative legacy of the Soviet past, when administrative buildings of this type had an unsightly, gloomy appearance, and the upper floors of high-rise buildings suffered from constant leaks. Over the past 10-15 years, the production of roofing materials has undergone significant changes, thanks to which it has been possible to create durable, strong and reliable polymer coatings of a new generation. From that moment on, flat roof house designs began to gain popularity.

Single-story - the traditional architectural form of southern coastal cities, resorts and luxury villas in the Art Nouveau style, where a mild climate prevails without large quantity precipitation. The main part of the territory of Russia is located in the zone of increased snow load, therefore, this construction technology began to be introduced recently, when modern roofing materials with improved performance characteristics appeared. Over the past ten years one-story buildings with a flat roof have been tested in harsh Russian winters and demonstrated the following advantages compared to pitched analogues:

Space saving. One-story houses with a flat roof, built according to frame technology, due to the rational use of space, they are a compact structure that can be placed on a small construction site within the city or in the suburbs. This quality is relevant in the context of a constant increase in the cost of land for development.
Saving materials. A flat roof does not have a slope, so less roofing material is spent on this type of roofing than on pitched analogues. Less wood is used during construction rafter frame, which reduces costs. In addition, flat roofs small size You can install it yourself without spending money on hiring professional roofers.
Possibility of expanding the area. A one-story house with a flat roof can become a transitional option until the need and financial opportunity arise to add a second floor. This versatility will be an additional advantage for young families, the composition of which may soon change.
Wide range of roofing options. If cottage equipped with a flat usable roof, it can be equipped with additional space to satisfy a variety of needs: equip sports grounds, recreation areas with barbecues, swimming pools, lay out lawns, beds or flower beds. For conservation-conscious homeowners natural resources, designs of houses with a flat roof on which solar panels are installed to provide “clean” energy are suitable.

Note! Roofing materials based on cardboard and bitumen impregnations, used in the past, had a service life of only 5-8 years, were damaged by sunlight, and cracked due to sudden temperature changes. But coatings made from fiberglass and synthetic rubber with polymer resins will protect the house for 50 years. New generation flooring materials do not require a gas burner, so they are suitable for DIY installation.

A roof that has no slope is called flat; it rests on all 4 load-bearing walls Houses. This design is a multilayer coating of rolled or self-leveling waterproofing materials, laid on a prepared base. Do-it-yourself installation of a flat roof is carried out by layering, pouring or gluing in the following sequence:

Base. The first layer of a flat roof is the base of concrete slabs, wooden beams or corrugated sheets, which are prepared in a special way. A primer is applied to it to reduce surface roughness and increase material adsorption.
Screed. Screed from cement-sand mortar serves as a leveling layer, with the help of which the roof is sloped, creating a slope in the places where water inlet funnels will be installed.
Vapor barrier. This layer of diffuse membrane roofing is a barrier to water vapor that penetrates from the heated room into the thickness of the roof, causing the insulation to become damp. To give the membrane strength, it is reinforced with fiberglass.
Thermal insulation. To protect a one-story house from cooling and heat loss through a flat roof, thermal insulation material is installed on it. For this, backfill insulation (expanded clay), glass wool, basalt fiber, slag wool or extruded polystyrene foam are used.
Waterproofing. Waterproofing of modern flat roofs is carried out using polymer rolls or self-leveling materials. Rolled coverings are laid in several layers to prevent leaks in the connecting seams. Liquid materials(liquid roofing felt, liquid rubber) make it possible to waterproof roofs of complex configurations; pre-heating is not required during their installation.

Important! The quality of installation of a flat roof on a one-story house depends on weather conditions. Experienced roofers and manufacturers recommend laying the coating in dry, warm weather, when the temperature exceeds 5 degrees. At low temperatures, the lower layer of bitumen materials takes longer to heat up, so installation takes longer and gas consumption increases.

Types of flat roofs

Single-pitched houses with a flat roof fit organically into the urban landscape and look just as good as a country residence. Abundant glazing, use in decoration natural materials make the structure light, filled with light and spacious, despite its small size.

Depending on the nature of use and financial developers, the following types of flat roofs are used in projects: Important! the perimeter is fenced with a parapet, a protective barrier that holds snow masses and rainwater from a spontaneous discharge. On exploited roofs, the parapet acts as a fence that prevents people from falling, so it must have a height of at least 1.2 m.

Construction and finishing. Equipment. Wallpaper. Coloring. Facade

Houses with a flat roof projects. Flat roof for a private house: a general overview of construction technology

What is a flat roof?