When gluing polystyrene EPS (Expanded Polystyrene) boards to insulate external walls, it's important to follow proper procedures to ensure effective insulation and adherence. Here are some general rules and guidelines:

1. Clean the Surface:
   - Ensure that the surface where you will be attaching the EPS boards is clean, dry, and free from dust, dirt, grease, or any other contaminants. A clean surface promotes better adhesion.
2. Prime the wall before gluing the insulation boards.
   - There are generally two rules. The first one concerns absorbent substrates and requires a deep-penetrating primer, such as Atlas Uni-Grunt or Multigrunt. The second is a wall with a non-absorbent substrate, such as old clinker brick or pebbledash, and this type of substrate requires a contact primer, such as Atlas Cerplast.
3. Choose the Right Adhesive:
   - Use an adhesive specifically designed for bonding polystyrene EPS to various substrates. Common adhesives for this purpose include polystyrene-compatible construction adhesives or specialty EPS adhesives.
4. Apply the Adhesive Correctly:
   - Follow the manufacturer's instructions for applying the adhesive. This usually involves applying glue around the edges and in the center of the back side of the EPS boards to prevent surface deformation and to protect the wall from potential vertical spread of fire during use.
   Places where smoke or fire could potentially penetrate can be additionally insulated with specially designed low-pressure VOLT low-expansion foam, which can withstand temperatures up to 850 ℃.
5. Use the Right Amount of Adhesive:
   - Avoid using too much adhesive, as excess adhesive may not improve bonding and can create a mess. On the other hand, using too little adhesive may result in inadequate bonding.
6. Press Firmly and Evenly:
   - After applying the adhesive, press the EPS board firmly and evenly against the wall. This helps to ensure good contact and bonding between the adhesive, EPS board, and the wall surface.
7. Secure with Mechanical Fasteners:
   - Glued boards usually require fastening using dedicated mechanical fasteners (screws or nails) in addition to the adhesive. It is optimal to install four dowels on one 1000x500mm board, i.e. 4 x 1/4 dowel in each corner of the insulating board, 2 x 1/2 dowel on each longer side and two dowels in the middle of the board - see the attached illustrative drawing that we have prepared for you in IBB.

    Properly insulated walls should not have thermal bridges, therefore the places where the mounting pins are recessed in the insulating boards should first be drilled with a crown drill, then install the pin and then cover with a special insulating disk.

Additional fixing of insulation boards with dowels is not necessary on smaller walls and not exposed to wind.
Remember to install the pins in the place where the glue was previously applied so that the pressure of the mounting pin does not deform the wall surface.

8. Allow for Expansion Joints:
   - If the insulated wall consists of two or more separate structural parts, remember to use expansion joints.
9. Protect from Rain during Installation:
   - If the installation is taking place outdoors and there's a chance of rain, take precautions to protect the EPS boards, adhesive and thin coat render from getting wet. We offer perfect for this purpose thin protective foil specially produced for us, measuring 2 x 50 m, to protect larger wall surfaces against precipitation.
10. Follow Local and National Building Codes and Guidelines:
    - Adhere to any local building codes and guidelines related to the installation of exterior insulation systems. Some areas may have specific requirements for insulation materials and installation methods.

Always refer to the specific product recommendations and guidelines provided by the adhesive manufacturer and follow best practices for the type of insulation and wall substrate you are working with.
In our three branches: IBB London, IBB Birmingham and IBB Manchester, we have been organizing training for installers of EWI External Wall Insulation systems with the participation of manufacturers' representatives for over 10 years.

External Wall Insulation tranining organised with ATLAS - London, July 2011 

Watch one of our last training procided in 2023

The products we offer come from the most experienced companies on the demanding Polish market in this technology, i.e. ATLAS and SEMPRE, and also have BBA certification.