External wall insulation is one of the most effective investments in a building: it cuts heat loss, improves comfort and protects the facade. But the result depends enormously on the quality of the installation. Here's what you need to know before you start.
What external wall insulation is
External wall insulation (also known as ETICS — External Thermal Insulation Composite System) is a set of layers applied to the facade: adhesive, insulation board, reinforcing mesh, base coat and decorative render. All the components work together as one system — which is why mixing materials from different manufacturers is not recommended.
The benefits it brings
- Lower energy use: less heat lost in winter and more coolness kept in summer.
- Consistent comfort: warmer internal walls and fewer temperature swings.
- Facade protection: the wall is shielded from freeze-thaw and cracking.
- Renewed appearance: the facade gets a clean, uniform finish.
Types of insulation
Expanded polystyrene (EPS)
The most widely used, with a good price-performance ratio and easy to install. Suitable for most residential and commercial buildings, provided fire-safety requirements are met.
Basalt mineral wool
More expensive, but non-combustible and better at sound insulation and vapour permeability. Often required for tall buildings or where fire regulations demand non-combustible materials.
The installation stages
- Preparing the substrate: the facade must be clean, dry and stable.
- Bonding the insulation boards and mechanical fixing with anchors.
- Applying the base coat and the reinforcing mesh.
- Priming and applying the final decorative render.
Mistakes to avoid
- Applying onto a damp or unprepared substrate — the system won't bond properly.
- Too few anchors or wrong positioning.
- Working in frost or extreme heat, outside the recommended temperatures.
- Mixing components from different systems, which voids the warranty.
- Ignoring the details at corners, reveals and the plinth, where water ingress most often appears.
Conclusion
A well-installed insulation system lowers your bills and protects your building for years, but a poor installation soon shows through cracks and water ingress. We carry out external wall insulation and facade works in Iasi, Bacau, Suceava, Brasov and other cities, using complete systems from a single manufacturer and respecting the application stages and temperatures. That's how a facade lasts and looks good over time.