New Screed and Spray Foam Insulation on a Roof

1. The pump

The screedScreedA layer of sand-and-cement mix or lightweight concrete poured over the slab to create falls and a solid surface for the next material. is pumped straight up onto the roof, so it can be spread quickly over the whole surface.

2. Spreading

The material is spread and levelled across the roof. A level, solid base is the first step to good insulationThermal insulationA layer of material that lets heat through only slowly, so a home keeps its warmth in winter and stays cool in summer..

3. The new base

Once the screed has dried, the roof has one continuous base for the next layers.

4. Bitumen primer

A bitumen primerPrimerThe thin first coat that goes on before the main material. It binds dust, seals the pores and helps paint or waterproofing stick firmly. goes over the whole surface. It binds the dust and helps the next material stick firmly.

5. Around the solar heater

The primer reaches everywhere: around the solar heater, the protruding steel bars and the foot of the parapetsParapetThe low wall around the edge of a flat roof or balcony. The joint between it and the floor is one of the most common places for leaks..

6. Spraying the foam

The polyurethane foamSpray polyurethane foamA foam sprayed on as a liquid that expands on the spot and sets into one seamless layer. It insulates against heat and cold and closes cracks and joints. is sprayed over the primer and expands into one continuous layer with no joints.

7. The result

The foam insulates and waterproofsWaterproofingThe work and materials that stop water getting through on flat roofs, balconies, bathrooms, basements, planters and tanks. in one go. The home below is protected from rain and from the summer heat.