Spray Foam (Polyurethane Spray): Sprayed as a liquid, it expands to fill all cracks and corners, making it the ideal choice for concrete roofs and corrugated metal (Shinko). Expanded Foam Boards (EPS): Lightweight, ready-made boards, often used under tiles or for thermal insulation. Extruded Foam Boards (XPS): High-density, durable boards used on surfaces subjected to heavy loads. Types of Foam Insulation Compared by Use Foam Type | Best Use | Key Advantage -|-|- Polyurethane Spray | Uneven surfaces and Shinko | Covers cracks completely and without gaps XPS Boards (Extruded) | Concrete surfaces under tiles | High resistance to pressure and water EPS Boards (Expanded) | Economical thermal insulation | Lightweight and economical Basic Implementation Steps Thoroughly clean the surface of dust and oils. Spray the foam layer to the desired thickness (usually 3 to 5 cm). Apply a protective coating (acrylic or UV protection) to protect the foam from degradation due to sun exposure. If you are planning to carry out insulation, I can help you with the following: