According to statistics, heat losses through a poorly insulated roof, pitched or flat, make up almost a third of the total. By taking a set of measures to install a thermal barrier, you can not only reduce heating costs, but also get additional living space, into which the attic is converted after completion of work.
Properly conducted measures increase the service life of the entire roof structure and create the necessary microclimate for life. The correct structure of the roof necessarily includes the following elements:
- roofing covered;
- rafters;
- crate;
- counter-lattice;
- vapor barrier;
- waterproofing;
- insulation;
- space for ventilation.
To understand how to insulate the roof of the house from the inside, it is first desirable to understand the basic physical processes that occur inside the roof structure, as well as to recognize the influence of the basic natural forces that she has to face daily.
Atmospheric exposure
Any roof throughout the year is influenced by many climatic factors requiring protective measures. These include:
- ambient temperature, fluctuating throughout the year and leading to heating or cooling of the coating;
- precipitation in the form of rain, which the roof is particularly susceptible to almost the whole year;
- precipitation in the form of snow, which create an additional load on the roof;
- the influence of wind, which implies reliable fixation of the coating to the structure.
Thus, the main task of the roof of the house is to create reliable protection against these influences and maintain comfortable living conditions indoors, which are characterized by a stable temperature and humidity level.
Physical processes inside the roof
The constant temperature difference inside and outside leads to continuous physical processes that are of fundamental importance for understanding how to insulate the roof of the house from the inside. These include:
- heat exchange resulting from temperature differences outside and inside the house and leading to heat loss through the roof, which is prevented by the located insulation;
- moisture exchange, which is a consequence of human life (from breathing to cooking), as a result of which warm air saturated with liquid vapor rises, and is prevented by located insulation and a special clearance for ventilation.
The value of physical processes in home insulation
A properly located insulation with any temperature differences has a temperature on the outer surface only a few degrees higher than on the street.
The use of a steam insulator and a ventilation gap prevent the accumulation of condensate formed after cooling the steam in the heater and prevents not only its damage, but also the safety of the entire roof structure.
A good example of how to properly insulate the roof of a house from the inside can be seen if you look at the roof in houses after snow falls. If it is absent in whole or in part, icicles hang around the perimeter, which means that the work was carried out in violation of the rules. This is due to increased heat transfer, as a result of which the roof of the house is heated by hot air. coming from the premises, and as a result, the snow melts.
The sequence of work
Before you insulate the roof of the house from the inside, as in any work, you need to prepare a plan, draw up an estimate and prepare the inner surface of the roof.
The plan includes the implementation of the main stages, a list of the necessary tools and measurements of the roof area. In addition to the laying of insulation, it is necessary to provide for the finishing lining, communications (for example, electricity), the installation of windows or doors. This will turn the attic into a full-fledged living space.
After the measurements, an estimate is prepared and material is purchased, usually with a margin of about 15%. The choice of material and its thickness occupy a key place in the whole process, so it can be distinguished in a separate stage.
It’s nothing difficult to do all the work yourself, no. But to reduce the risk of errors, it is recommended that you carefully read the steps and tips below before you insulate the roof of the house from the inside with your own hands.
Work is carried out in the following order:
- surface preparation and choice of insulation;
- installation of a ventilation gap and waterproofing;
- installation of insulation;
- installation of vapor barrier;
- finish coating installation.
Surface preparation and choice of insulator
Before starting work, the roof structure must be checked to detect damage, deterioration or other defects. Violations must be corrected, damaged elements replaced, wooden surfaces treated with impregnation or varnishes. These actions will protect the structure and eliminate the need to dismantle future layers of thermal protection for repairs.
The most common materials used for insulation are today:
- mineral wool, in rolls or mats;
- Styrofoam;
- polystyrene foam.
They meet the basic requirements for insulation: safety, lightness, poor thermal conductivity and duration of operation. The use of glass wool indoors is not recommended. It is inconvenient to stack, and microparticles adversely affect health.
The minimum thickness of the insulator, used almost everywhere, is 150 mm. In most cases, this meets the requirements of building codes.
The shape of the roof affects the choice of material. For small spaces with a limited plane, laying rolls or mats can be difficult. In this situation, there is only one way out: how to insulate the roof of the house from the inside - with foam or polyurethane foam. They are sprayed with a special pump, usually in several layers. But in this case, the help of specialists with professional equipment is needed.
Installation of ventilation clearance and waterproofing
The space for ventilation of the insulation helps prevent it from getting wet and spoiling, which inevitably leads to the loss of protective properties. The minimum distance that should separate it from the roof surface is 20 mm. This allows excess moist air, which still pass from the room through the insulator, to be freely removed from the surface of the insulation.
The simplest waterproofing, still widely used in construction, is a common roofing material. But to create a more effective protection, it is desirable to use a special fabric with vapor permeability. The best option is diffusion rather than ordinary membranes. In this case, only one ventilated gap is sufficient. For the usual version, they need two:
- between a heater and a waterproofing cloth;
- between insulation and roof covering.
These measures are the result of continuous physical processes occurring under the roof. But, for example, before insulating the roof of the house from the inside with expanded polystyrene, these actions are not performed, since this material does not absorb moisture, which allows neglecting the hydraulic protection and ventilation gaps.
The insulation is laid with the smooth side to the roof on specially fixed bars with an overlap of at least 100 mm, perpendicular to the rafters, after which it is fixed with brackets or nails. During installation, an easy overhang is done to reduce the risk of damage during installation of the insulation. The joints are glued with tape. Waterproofing should completely cover the rafters.
Insulation Installation
The most crucial stage in the work process is “how to insulate the roof of the house from the inside”. Depending on the selected material, there are subtleties of working with it. But the principles apply to all species without exception.
The width of the insulation should be 10 or 20 mm greater than the opening where it is placed. The standard pitch of the rafters is 600 mm, which corresponds to or a multiple of the size of most heaters.
Fastening is carried out due to the dense structure of the insulation and the gap in size. But in addition it can be fastened with thin rails or a cord laid between nails or self-tapping screws screwed into the rafters.
Styrofoam and cotton sheets should completely fill all the free space. One of the installation options is the installation of insulation in two layers. In this case, the second is set so as to completely overlap the joints of the previous one.
Installation of vapor barrier
After completing the installation of the insulating material, it is imperative to fix the vapor barrier. The rough side is installed inside the room, as it absorbs steam, smooth - to the insulation. As with the installation of waterproofing, two points are important here:
- setting the right side to the insulation, otherwise the effect will be completely opposite;
- fixing all joints with double-sided tape.
Fastening is done using brackets to the rafters. Over the insulation, a crate is sewn for fastening the future finish. To do this, you can use any finishing material: plastic, wood or drywall.
To understand the individual stage of the process, how to insulate the roof of the house from the inside, the photos located at the beginning of the article and below will help with this.
Features of insulation of different buildings
Despite the fact that the main technological process is typical for warming different types of roofing structures, the use of each material has its own characteristics. For example, to date, there is no unequivocal majority of adherents on the question of how to insulate the roof of the house from the inside - with foam or cotton wool. Each material has its pros and cons.
In houses with an attic, insulation allows you to get a full-fledged living room where you can live. The absence of the need for a warm attic will probably reduce the process of roof insulation to a minimum if this is done first with the floor.
For most flat roof structures, the best option is to start the insulation work first from the outside. And only in the absence of effect, start work inside.
If we consider the process of how to insulate the roof of a wooden house from the inside, then its main feature is the thorough surface treatment with protective impregnations or varnishes, and the minimum weight of the insulation.
Tips for all occasions
If the work is carried out independently, it is advisable to always follow the main rules:
- eliminate roof defects, and not mask them;
- carefully treat wooden surfaces, especially rafters;
- work only together.
Despite the simplicity, perhaps these rules will become the determining factors in the durability of the roof of a residential building.