How to insulate a ceiling with penoplex, installation options, how to do everything correctly

Insulating a house, especially an old one, is always a hot topic. This is especially important in our time, when energy resources are rising in price every day. When carrying out thermal insulation, you need to take into account that this is a complex undertaking. The maximum effect can be achieved only by thermally insulating the floor, walls and ceiling. And not only heat insulation, but also sound insulation depends on quality work. Experts unanimously say that insulating the ceiling with penoplex can significantly increase the comfort of living. But, unfortunately, most people do not attach much importance to this, which ultimately leads to disappointment after the procedures. Today we will talk about the thermal insulation procedure using this material. But first, let’s figure out what it is and why it is advisable to choose it when carrying out this procedure.

What is penoplex?

The market for polymer materials that are used for insulating rooms is overflowing with a wide variety of options. The assortment can confuse not only beginners, but also professionals. Experienced experts recommend giving preference to penoplex over other insulation. The reason for this is the excellent physical and chemical properties that are made from extruded polystyrene foam (EPS), it is one of the most versatile materials used in a variety of industries. But penoplex has found its widest use in insulating buildings, from the foundation to the roof.

When insulating EPS, you can obtain a number of properties that are not available when using other types of insulation. Among them are:

  1. Environmentally friendly material;
  2. Due to the presence of small pores, penoplex acquires low water absorption and at the same time vapor permeability remains at a normal acceptable level;

Agree, not every finishing polymer material can boast such excellent properties. At the same time, penoplex does not weigh down the structure due to its low specific gravity. Thanks to the small pore sizes, excellent thermal and sound insulation performance can be achieved with a small thickness. When insulating the loggia ceiling with penoplex, you can pay attention to a number of positive qualities. They are:

  • ease of installation;
  • you can do everything yourself without much difficulty;
  • due to the lack of influence of weather conditions on the characteristics of this type of polystyrene, its installation is carried out under any circumstances.

What insulation should be used for a pitched roof?

Despite the very wide range of materials for insulation, you should not look towards economical options. The principle is relevant here: the miser pays twice. By choosing the wrong insulation or deciding to save a little, you may not achieve the desired effect and end up with an extra problem.

Don't make a mistake!

Remember, the roof is where warm and cold air flows meet, where temperature changes are most noticeable. Moisture can penetrate here and there is a possibility of freezing.

Therefore, by choosing a thin and insufficiently porous material, you can grow mold in your attic, which is sometimes simply impossible to remove. Moreover, moisture and mold can destroy the wooden beams that form the basis of the roof.

Also, when choosing insulation for a pitched roof, pay attention to:

  • weight - the higher it is, the greater the load on the structure itself;
  • resistance to mechanical, temperature and climatic conditions;
  • thermal conductivity - the lower it is, the safer the material will be.

Suitable for insulating a pitched roof:

  • Pressed mineral wool.
  • Glass wool.
  • Styrofoam.

Also, special attention should be paid to the softness and elasticity of the insulation, since it must fill all the voids between the rafters when insulating the roof itself. Insulation technology includes layer-by-layer placement of materials that can retain heat in the house and prevent moisture penetration

Preparation for installation

To successfully install EPS on the ceiling, you must prepare tools, consumables and the surface. This will make it possible to carry out thermal insulation in one go, without stopping. So, for this you will need:

  • level;
  • perforator;
  • stationery or construction knife;
  • hammer;
  • ladder.

As for preparing the base, it must initially be cleaned of all debris and dirt. In this case, it is advisable to level the ceiling so that the slabs lie without curvature or gaps. This work can be done using plaster. All holes, cracks and potholes are sealed with putty.

To perform the installation yourself, you will need the following materials:

  • antifungal primer;
  • dry glue for working with tiles;
  • polyurethane foam;
  • fastening tools (fungi).

When preparing the surface, it is initially cleaned of dust and debris. If leveling was carried out, then it is very important to also remove all the excess. Next, the ceiling is primed and treated with a special antifungal mixture. When the surface is dry, work can begin.

Carrying out work

At the moment, there are two options for thermal insulation of the ceiling with polymer:

  • thermal insulation from the attic;
  • thermal insulation on the inside.

Isolation using the first method is significantly better than the second. The fact is that there is no need to “steal” the useful volume of the room, and the time and effort required is significantly less. Additionally, all work is carried out as if it were a floor in the room.

Installation from the attic

The technology for installing EPS using this method consists of the following steps:

  • First, the surface is thoroughly cleaned of debris, dust and other pollutants;
  • An adhesive mixture is applied to the surface of the slabs, and the elements are laid on the attic floor;
  • the procedure must be performed with minimal gaps;
  • after the glue hardens between the plates, where there are gaps, sealing is done using polyurethane foam;
  • After a day, the remaining foam is cut off, and if you plan to use the attic in the future, then boards or wood boards are laid on top.

As a result of this work, excellent thermal and noise insulation performance can be obtained. It is worth considering the advantages of this method in the form of the absence of insulation elements from the inside of the room.

Material selection criteria

It is important to understand that only high-quality material is selected for a reliable layer of thermal insulation. Therefore, when buying expanded polystyrene, do not make a choice on the first one you come across, focus on the following criteria:

  1. Availability of quality certificates and related documentation.
  2. Manufacturing standards. If the documents indicate specifications, refuse such products; GOST gives the green light to purchase.
  3. Marking - PSB-S is suitable for facade insulation; this material is treated with fire retardants, which means it will extinguish on its own in the absence of a fire source.
  4. Density not less than 40 kg/m3. Other options are not suitable for facade insulation.
  5. Try breaking off a corner of the slab of the option you like. The scrap should be smooth, and the visible elements (balls) should have the shape of a polyhedron. If this is not the case, the option is suitable for packing things during transportation, but it will not withstand the load that the facade is subject to.

Installation from the room side

It often happens that work from the attic side is impossible. The reason may be the presence of neighbors above, or simply the absence of such a part of the building. In this case, it is necessary to carry out insulation from the side of the room, which complicates the procedure a little.

So, the instructions for carrying out the work are as follows:

  • First, the surface is cleared of debris and all cracks, holes and gaps are sealed;
  • then the surface is treated with a primer and antifungal mixture;
  • An adhesive mixture is applied to the insulation boards and they are attached to the surface;
  • Using a hammer drill, holes are drilled for the fungi. It is worth considering that this procedure is carried out with a ceiling to which penoplex is already partially fixed;
  • after making holes, fungi clog in them, which makes it possible to hold the slabs more securely;
  • then all joints and gaps are treated with polyurethane foam;
  • after the foam has hardened, its remains are cut off and the reinforcing mesh begins to be attached using a rough adhesive mixture;
  • after this, the surface is cleaned, primed and another layer of finishing is applied to it;
  • Thermal insulation work is completed with final surface finishing (painting or applying a decorative coating).

Insulating the attic ceiling

If the attic can be used as an attic, then it is also important to insulate the ceiling using penoplex. Thanks to its high thermal insulation and sound absorption rates, it can be used to make the attic space as comfortable and habitable as possible. But the procedure for attaching the slabs is slightly different here.

To do the work yourself you will need to take the following steps:

  • from the very beginning you need to prepare the area for fastening. This procedure is no different from the above insulation options;
  • Next, you need to assemble the sheathing and attach the insulation boards to it;
  • after this, all joints are sealed with polyurethane foam with a minimum expansion coefficient;
  • after this, boards or chipboards are attached, which close the gap with the heat insulator.

Next, everything is done in exactly the same way as when decorating a regular room.

Experts have noted that installation of this insulation can be carried out even in the attics of old houses.

Economic effect

The use of this polymer has a positive effect not only on physical characteristics, but also on the budget. So, this material is noted for its rather low cost. This allows it to be used by people of any income.

Expanded polystyrene also makes it possible to reduce further space heating costs. The reason for this is reduced heat exchange with the external environment. Everyone knows that heated air is lighter than cold air. For this reason, insulating the ceiling with penoplex will limit contact with a cold surface.

Foamed extruded polystyrene has a fairly low weight, which ensures that there is no unnecessary load on the ceiling. This characteristic is very important in houses that were built a long time ago. Over time, they begin to lose their stability and strength. Carrying out a major renovation requires a lot of effort. Conventional insulation with this polymer material will make it possible to radically change the interior appearance of the room and at the same time reduce the heat transfer of surfaces, retaining all the heat inside.

The issue of thermal insulation of a home, especially if it is carried out in an old house, is always relevant. This is also due to the annual increase in tariffs for thermal energy sources, which most often are natural gas and electricity. When arranging thermal insulation, do not forget that this coating must be produced as a complex. Achieving the maximum effect is possible only when the insulation affects the surfaces of the floor, ceiling and walls. If the work is done efficiently, the level of living comfort will increase, for which not only thermal insulation, but also sound insulation is important. Professionals confidently claim that insulating the ceiling with penoplex can significantly increase the level of comfort in the room. Many people do not give such advice the importance it deserves. This only leads to the fact that the work performed is not very energy efficient.

Heat loss at home

If we consider the cooling map of a building, the floor accounts for up to 40% of heat loss. Accordingly, not only it should be insulated, but also all other elements of the building - the roof and walls. An integrated approach makes it possible to maintain a constant temperature in the house both in summer and winter.

The industry does not offer many materials for such work, so today we will focus on one - penoplex, which:

  • easy to use;
  • manufactured using a high-tech method;
  • makes it possible to create the optimal temperature in the room.

Just like polyurethane and expanded polystyrene, it is a type of foam plastic. Therefore, its technological characteristics fully meet our needs.

Proper insulation of a wooden house with penoplex

Extruded polystyrene foam (EPS) or penoplex

The market for building materials produced on the basis of polymer compositions and used for thermal insulation of residential premises is replete with various options. The assortment presented in stores can confuse not only inexperienced builders, but also professionals in their field. Experienced builders recommend opting for penoplex rather than other types of insulation such as “XPS TECHNOPLEX”. The reason for this is the presence of special properties in this material related to its composition and structure. Thanks to them, extruded polystyrene foam is a material with a universal scope of application. Most often, this material is used specifically for thermal insulation in private homes, commercial and industrial buildings. It is mounted both in the area of ​​the foundation and walls, and is used to insulate the roof space.

The use of extruded polystyrene foam allows you to take advantage of a number of its unique properties that other types of materials cannot boast of when insulating a ceiling with a cold roof. These include:

  • Environmental safety of insulation.
  • The presence of microscopic pores in the structure of penoplex causes a low level of moisture absorption without compromising acceptable vapor permeability values.
  • Penoplex is not susceptible to fungal infections and mold, and is not destroyed by environmental factors. It is completely protected from rotting.
  • The material is characterized by increased strength, thanks to which its slabs are able to withstand significant mechanical loads. This quality makes it possible to use penoplex for thermal insulation not only of ceilings, but also of walls and floors.
  • The edge of the insulation looks like a protrusion in the shape of the letter “L”. This feature greatly facilitates the process of joining the slabs, and also guarantees that all the cracks will be filled with material.
  • The surface of the penoplex is rough, which ensures good adhesion characteristics with finishing materials - putty, plaster.

It is difficult to disagree with the fact that not every finishing material made on a polymer basis has a set of such important qualities. In addition, penoplex slabs weigh little, which means they do not create additional load on the structural elements of the building. Since the pores of the material are very small, it can serve as an excellent means of thermal and sound insulation, while its thickness is small. Those who happened to use this material to insulate the ceiling space of the loggia noticed a number of other useful properties.

They are as follows:

  • ease of installation;
  • the ability to independently carry out work without difficulty;
  • work on installing penoplex slabs can be done without regard to weather conditions, since it is not afraid of either frost or moisture.

How to insulate?

In order to insulate a room inside, several types of materials are used. Most often, a special heat-insulating material is used, which is called glassine. It has the following advantages:

  • economically beneficial;
  • practical;
  • resistant to temperature changes;
  • resists moisture well.

Insulation materials with similar characteristics are also popular. These include the following:

  • nenofol;
  • expanded polystyrene;
  • isolon;
  • penoplex;
  • technical wool;
  • cork.

7 photos

PVC film is most often used as waterproofing, which reliably protects against leaks. Its service life is several decades. It is profitable to use film, because it is inexpensive.


Drywall is good because it provides a perfectly flat surface without seams; it can be used to create any type of ceiling. To work with drywall, two types of lathing are used:

  • made of wood - it is easier to work with such material, it costs less;
  • made of galvanized profile - is more durable, does not deteriorate under the influence of temperature changes, and is not susceptible to mold or mildew.

Technical wool

Ceiling insulation in a private household using technical wool is carried out in the following way:

  • using a stapler, a PVC film is mounted to the ceiling, which will reliably protect against moisture getting on the slabs;
  • the lathing is made of wooden blocks in increments of 40–50 cm. The size of the block must correspond to the thickness of the thermal plates, that is, it must be 5 cm;
  • slabs of technical wool are laid and secured with special mounting rails. This design is reliable and simple, not subject to deformation.

Mineral wool has several important characteristics.

  • Low thermal conductivity - 0.036 W/ (m*K); for insulation, a layer of no more than 10 cm is sufficient, which corresponds to the usual thickness of load-bearing beams.
  • The material has increased vapor permeability; for 50 kg of weight per cubic meter the coefficient is 0.7 mg/ (m*h*Pa). This figure is higher than that of wood.
  • Slight hygroscopicity, that is, upon contact with liquid, the material will absorb no more than 2% of moisture from the total volume.
  • Mineral wool slabs have high fire safety. Such insulation is non-flammable and does not contribute to the spread of fire.
  • Mineral wool has good soundproofing characteristics and is capable of effectively blocking sound waves of various frequencies. It is especially beneficial to use basalt insulation, because it does not deform and has a long service life. One package is enough to treat about twenty square meters.
  • The material is not susceptible to the harmful effects of fungus or mold, and has antiseptic properties.
  • The porous material, which has a low specific weight, cannot be burdensome for supporting structures, which contributes to a long service life.

Condensation has a detrimental effect on industrial wool; it inevitably loses its beneficial properties. PVC slabs are not afraid of moisture and are not subject to erosion or the spread of fungus. The advantages of mineral wool are that it is not afraid of moisture and does not become damp. Mineral wool is cheaper than PVC boards, does not contain toxins, foam boards emit harmful components.

Features of polystyrene installation

  • The foam sheets must be laid in such a way that they fit as tightly as possible to each other, without creating gaps. This will help ensure the most effective insulation of the surface.
  • For the attic, it is important to lay the sheathing in the space between the cells. To obtain maximum effect, the entire surface must be treated with insulation.
  • When insulating rooms, after laying penoplex on the ceiling, you must also make a decorative design of the surface - it is puttied, then treated with finishing plaster, and then primed.
  • Only after these measures can you begin to paint the ceiling or otherwise decorate it.

Advantages and disadvantages of polystyrene foam

The material is a cluster of styrene balls, inside of which there is air . Air and inert gases are the best insulation materials in the world. The more air in the material, the better its thermal insulation properties. The advantages of polystyrene foam (expanded polystyrene) include:

Table with foam characteristics

  1. Low thermal conductivity. The main characteristic of a heat insulator is its ability to conduct heat. The lower it is, the warmer the room will be. The thermal conductivity of polystyrene foam is approximately the same as that of mineral wool or extruded polystyrene foam.
  2. Low cost. Carrying out repairs or construction is always a costly undertaking. Polystyrene foam is an effective material that does not require large financial investments.
  3. Light weight. The mass of expanded polystyrene allows it to be used to insulate ceilings from the inside without any problems. The material adheres well to a horizontal surface. The smaller the mass of the insulation layer, the easier it is to fix it and the less likely it is to fall off during operation. Light weight when holding events in a private home also reduces the cost of delivering the material.
  4. Easy to install. The characteristics of the heat insulator allow even a non-professional to perform the work. To insulate the ceiling with polystyrene foam you do not need to put in a lot of effort.
  5. Safety. When installing insulation yourself in a private home, it is important to ensure the safety of the work contractor and residents in the future. The structure of the foam is such that even when destroyed, it crumbles into fairly large balls. They cannot harm humans. This distinguishes polystyrene, for example, from mineral wool, when using which it is necessary to use masks and gloves.

Dimensions of insulation material

The positive qualities of polystyrene foam have allowed it to firmly establish itself in the building materials market. But it has its own characteristics and limitations. Insulation with polystyrene foam has the following disadvantages:

  1. Styrene beads do not absorb water, so polystyrene foam has a fairly low degree of water absorption. The difficulty is that water can get into the space between the balls. Under normal conditions this does not cause problems, but if the ambient temperature drops, destruction will occur. The bond between styrene beads is not very strong. When water turns into ice, it expands, affecting individual particles of the material. With the simultaneous action of water and cold, the foam simply crumbles.
  2. Low fire safety. Polystyrene is not resistant to high temperatures. Now manufacturers are introducing special additives into the composition that make polystyrene a low-flammable material, but the problem remains.
  3. Low strength. This drawback is important when insulating the floor. For installation on the ceiling from inside the room, it is not necessary to use durable materials; weight becomes a more important factor here. Insulation from the attic side with polystyrene foam is also possible, but due to its strength it is laid between the joists or under a strong reinforced cement screed.
  4. Unnatural origin. This is also more of a feature than a drawback. Insulation materials of natural origin, such as sawdust or expanded clay, have low efficiency. Another type of natural insulation is ecowool. The material is effective and expensive. The last two points are not serious drawbacks when insulating the ceiling in a private house, so we can say that polystyrene foam has proven to be an excellent thermal insulator with a score of 5:2.


Before using the material for thermal insulation of the ceiling in the veranda or in the attic, you should first get acquainted with its properties. Polystyrene foam is a sheet material that is a frozen foam mass, most of the material is air, so it is very light and has good thermal insulation qualities.

Polystyrene foam is produced with different density indicators, this indicator affects the mechanical strength of the material.


Let's look at why many craftsmen prefer to work with foam plastic. This material has the following advantages:

  • low rates of heat and sound conductivity make it possible to recommend this material not only for insulation, but also for sound insulation of the attic, if metal tiles or slate are used as roofing;
  • resistance to moisture, polystyrene foam does not rot, does not absorb water, and does not contribute to the development of mold fungi;
  • the material is safe for health;

working with polystyrene foam is not difficult, it can be easily cut with a knife, so this material is recommended to be used if insulation work will be done with your own hands.

Disadvantages of use

But, of course, polystyrene foam is not an ideal material; it also has certain disadvantages.


low mechanical strength, so if you plan to carry out insulation yourself, then you need to be careful when cutting the plates and laying them; the material must be protected from exposure to direct sunlight, as it is destroyed when exposed to ultraviolet radiation; the foam itself is non-flammable, but when heated to high temperatures it begins to release toxic substances; low vapor permeability, which is why it can be damp in the attic room, insulated with foam plastic. To eliminate the shortcoming, it is necessary to consider a ventilation system; purchasing polystyrene foam will cost more than purchasing mineral wool

But when using mineral wool, high-quality waterproofing is required, which requires the purchase of additional materials. Therefore, the final costs are generally the same

purchasing polystyrene foam will cost more than purchasing mineral wool. But when using mineral wool, high-quality waterproofing is required, which requires the purchase of additional materials. Therefore, the final costs are generally the same.

Other varieties

As already mentioned, for thermal insulation of the attic it is better to use extruded polystyrene foam; the second name for this material is penoplex. Penoplex is made from the same raw materials as regular foam, the only differences are in technology.

Thanks to a special production technology, penoplex has greater fracture and bending strength. In addition, the material is too tough for mice. But working with penoplex is not difficult, the work can be done with your own hands, so if the attic insulation is done using penoplex, then the heat-insulating layer will not require replacement for many years.

Insulation methods

You can insulate the ceiling with polystyrene foam yourself from the outside and from the inside. The cold air side option provides greater efficiency and is scientifically correct. When insulating a private house, it is best to insulate the ceiling of the upper floor from the attic side.

This method is difficult if insulation is carried out in an apartment building. In this case, insulation from the inside is practically the only possible option. Insulation in the apartment is carried out not only to protect from the cold, but also from noisy neighbors.

If you insulate the ceiling from the inside with foam plastic, you can significantly reduce the noise level and create favorable conditions for relaxation.

As mentioned earlier, the combination of water and polystyrene foam is undesirable, therefore, when laying, two additional layers are provided: on the cold air side - waterproofing, and from the inside of the room - vapor barrier.

The procedure for carrying out work when insulating from the attic:

  • clearing the surface of debris, dust and dirt;
  • leveling if necessary;
  • vapor barrier;
  • laying logs (if they are needed);
  • laying foam plastic (it is necessary to provide a small gap between the insulation boards or between the insulation and the joists; the foam expands slightly after laying);
  • waterproofing;
  • pouring the screed (for the method without logs) with laying wire reinforcement with a diameter of 3-4 mm;
  • clean floor.

The last point is an optional step. You can leave a cement screed as a floor covering in the attic.

Thermal insulation of the ceiling in a private house from the inside is carried out in the following order:

  • ceiling cleaning;
  • installation of a frame (wooden or aluminum profile, this step is not necessary);
  • securing foam sheets;
  • vapor barrier;
  • ceiling trim.

Why insulate a wooden house

Although wood itself is a warm material and the floors in such a structure are somewhat different than in an ordinary apartment in a multi-story building, they also require care, and even more.

We recommend that you do not ignore thermal insulation, since in combination with it this durable and reliable material can be used for much longer. Therefore, for those who doubt whether it is possible to insulate a wooden house with penoplex, the answer is yes.

Let's look at two main reasons why insulate the floor, as well as the walls and ceiling, in a wooden house:

  • you can forget about mold and fungal formations;
  • Now, even after a fire, the high fire resistance of penoplex will prevent fire from spreading throughout the structure.

Insulating the outside of a wooden house with penoplex yourself will save on energy and protect it from the spread of fire

( 2 ratings, average 4.5 out of 5 )
Did you like the article? Share with friends:
For any suggestions regarding the site: [email protected]
Для любых предложений по сайту: [email protected]