Insulation of walls from the inside with foam and drywall

It is preferable to warm the room outside. In this case, a greater heat-saving effect is achieved, the supporting structures are protected from the influence of the external environment, the usable area is not reduced. But this is far from always possible, especially when it comes to apartment buildings. It is cheaper and more convenient to warm the walls of the house with plasterboard and foam inside.

The benefits of foam

With internal insulation under GCR, polystyrene, mineral wool or foam can be used. Polyfoam has not the best indicators of thermal conductivity, and mineral wool is hygroscopic, therefore, foam is more preferable for this method of thermal insulation. This is facilitated by its characteristics:

• Light weight plates.
• Ease of processing and shaping, which greatly facilitates installation. For example, if there is a window or a battery on the wall, it is easy to cut a piece of penoplex of the required size to get around them.
• Good moisture and vapor barrier performance.
• Good blunt-absorbing properties.
• Strength, durability, safety.

There are few disadvantages:

• The material does not tolerate prolonged exposure to the sun. Therefore, the rules for its storage must be observed.
• During operation, it can be damaged by rodents.
• Pretty expensive compared to other materials.

A few nuances that you need to know when installing a heater for drywall

As already mentioned, insulating walls from the inside is not the best solution due to some disadvantages of this method. Consider 3 main nuances:

1. The dew point offset. It is between the wall and the insulation, so the base can damp from the inside.
2. Reducing the size of the room. The heat insulator, frame, GCR occupy part of the internal space.
3. Reducing the allowable load on the floor surface. The insulation may not withstand heavy objects hung on the wall, therefore, if necessary, it is recommended to use anchors.

Necessary materials and tools

To lay the insulation under drywall you will need:

• The penoplex itself. For internal wall insulation use products marked "C" with a thickness of up to 30 mm.
• Reinforcing mesh, plaster and putty. Useful both for leveling the base surface, and for finishing drywall.
• Primer deep penetration and special for GKL.
• Adhesive designed for fixing foam.
• Vapor barrier.

For the frame method of installing drywall, penofol with a foil surface is ideal. It will reflect heat inside the room.

• Dowels. The insulation plates are fastened to their dish-shaped variety, and the metal profiles of the frame - to the dowel-nails.
• Guide and rack profile for frame construction.
• Self-tapping screws for fastening elements, direct suspensions and other necessary fasteners.
• Silicone sealant.

Instruments:

• Drill with a mixer and a container for the preparation of adhesive solution.
• Puncher with a drill for drilling holes for dowels, on which we will fasten profiles.
• Scissors for metal.
• Screwdriver.
• Paint knife.
• Spatulas and graters, sandpaper.
• Paint roller and primer brush.
• Marking tool: level, plumb line, tape measure, pencil.

Methods for laying foam plastic under drywall

There are two mounting options: with and without a frame. You can correctly lay the insulation under the gypsum board with your own hands in both ways, the main thing is to know their advantages and disadvantages.

• The frameless method is suitable for warming small and even surfaces. Quick, easy installation of insulation and drywall. Disadvantages: inability to level the base surface, low structural strength.
• The wireframe method is used if the walls are curved or have a significant area. It is more difficult to erect such a construction, but it is more reliable.

Penoplex insulation under drywall without frame

Step-by-step instructions will be as follows:

• At the first stage, the base surface is prepared: the old coating is removed, cracks and potholes are closed, the protrusions are knocked down. The wall should be as flat as possible.
• The surface is treated with a deep penetration primer.
• According to the manufacturer’s recommendations, a special composition is being prepared. If it is not, you can apply glue to the tiles.
• The inner part of the insulation plate is rolled with a needle roller. Another option is to brush it with metal. This will provide good adhesion to the adhesive.

The glue is applied to the surface of the sheet with a notched trowel. It is not necessary to cover the entire plate with the composition: it is enough to smear the perimeter and center, the options are shown in the photo.

• A fragment of insulation is applied to the wall and held for a minute. Be sure to control the correct installation of the building level.
• Start sticking foam from below. The rows are recommended to be shifted relative to each other so that the plates are staggered.

For reliability, penoplex is fixed with dish-shaped dowels: 4 are placed at the edges and one in the center.

• The joints between the plates are filled with silicone sealant, wide cracks can be covered with foam.
• Drywall is attached to the insulation with glue. The scheme for applying the composition is the same as for foam boards. It is recommended to place a vapor barrier between them.
• After the glue dries, which takes 24 hours, the drywall is finished. Seams are repaired with putty and a serpentine net, wiped, after which the entire surface is covered with a double layer of primer.

Warming with a frame

The procedure for choosing this installation method will be as follows:

• The surface of the wall undergoes minimal processing: poorly-held elements of the old coating are removed.
• The frame is marked up: a strip is drawn on the ceiling, then with the help of a plumb line it is transferred to the floor. These are the guide rail attachment lines. On the wall is the location of the uprights in increments of 60 cm.
• The guides are fastened with dowels. Mounting step - 25-30 cm.

• Vertical elements are mounted. They are screwed to the guides with metal screws. The deviation is adjusted using direct suspensions located every 50-60 cm. The position of the racks is checked by the building level.
• Penoplex is glued to the wall in the same way as with the frameless method. Insulation plates are rolled with a roller with needles, adhesive solution is applied. Then they are firmly inserted between the uprights and pressed for 40-60 seconds.

Tip. Pieces of insulation are placed in the metal profile to prevent heat transfer through the racks. Another option is to fill them with foam.

• Drywall sheets, if necessary, are cut into desired fragments. GKL docking occurs strictly on racks. Fixation is carried out with self-tapping screws in increments of 25-30 cm. In order not to damage the surface of the drywall during installation, a special bit is put on the screwdriver, limiting the depth of twisting of the self-tapping screw. You can find it in hardware stores.
• Is produced joint repair using reinforcing tape and putty. After grouting, the entire wall is covered with two layers of a special primer on drywall. The second layer is applied after the first has dried.

Thus, to insulate the walls of the apartment from the inside, using foam and drywall, it is quite possible with your own hands. If everything is done correctly and accurately, then the desired effect will certainly be achieved. The process in detail can be seen in the next video. And if you have questions along the way, ask them in the comments.