Styrofoam Insulation On Flat Roof

Once the roof demo was complete and the flat roof was cleared of any remaining debris some rotted 2x material around the perimeter of the roof was replaced.

Styrofoam insulation on flat roof.

While expensive the best insulation is polyiso rigid foam. For a 1 inch board equivalent of 6 r value. Different types of roofing insulation exist including blanket insulation blown insulation and rigid insulation. It provides r values that range from 3 6 to 4 2 per inch.

Foam control plus provides more r value at a lower cost xps use blowing agents that cause r value loss over time. Also called styrofoam insulation this is the least expensive material. Foam control plus available in 15 25 40 and 60 psi strengths at a lower cost foam control plus has a superior drying potential foam control plus is more vapor permeable to help avoid moisture problems. However most cathedral ceilings and low slope flat roofs are insulated roof assemblies.

Such an insulating solution involves applying several layers of pur foam with each layer around 1 2 cm thick. A roof over a vented unconditioned attic does not need to include any insulation. Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces. Flat roof insulation installation the rigid foam board insulation we used was 2 thick and came in 4 x 8 sheets.

We recommend having at least 20 r value worth of material for optimal energy efficiency. Closed cell polyurethane spray foam will prove ideal for thermal insulation of a flat roof. Some products have reinforced facing to make them sturdier. Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.

The foil insulation goes on top of the moisture barrier followed by the roof covering. With a flat roof however this becomes a major concern. The type that is right for your flat roof insulation job depends upon the state of the roof expert opinion on the best type and your budget. You can expect to pay about 55 100 sq ft.

If you use bubble foil or rigid foam insulation it also goes on top of the moisture barrier. Rigid foam panels are available in thickness. With this kind of roof the insulation follows the slope of the roof. Use rigid foam insulation panels on your flat roof before applying the final roof covering or inside the house before adding sheetrock or paneling.

The effective roof insulation layer may range in thickness from 3 to 12 cm as needed.