Rigid Insulation Over Tpo Roof
The vapor barrier protects the roof insulation from the vapor included in the interior air.
Rigid insulation over tpo roof. The plywood. A roof over a vented unconditioned attic does not need to include any insulation. 27 x29 flat roof with 5 8 plywood sheathing. Insulation board should be added between the old and new roof systems to ensure proper insulation and to reflect heat from the outside.
There is 1 4 of iso at the edges built up to approx. Achieves fm vsh approval with adhered 60 or 80 mil smooth back jm tpo membrane and standard jm tpo membrane adhesives when 4 x4 panels are adhered in low rise foam adhesive ribbons 12 o c. Rigid foam insulation installation prepare roof deck. The bottom layer of a single ply membrane roofing system is the roof deck or substrate.
This sandwich will cost a bit more in short term but it s much cheaper than tearing off new deck to fix leaks. Available in both foam and rigid form choose the board type. The first step with roof installation is to prepare the roof deck by getting rid of all dirt dust and contaminants. Payback is not the way to do it at least not in my.
Coated fiberglass facer ideal for fully adhered systems provides a broader compatibility and higher performance with. Best to use 2 part adhesive foam to attach insulation to roof substrate and then glue tpo over iso this way there are not screws under tpo minimizing punctures from underneath. The energy argument is argumentative. The rigid insulation over roof would have controlled the temperature of the condensing surface the underside of the roof deck so that i would not have had to use the spray foam except at the perimeter to provide the air seal to the tops of the walls.
There is no ice water or vapor barrier under the iso. Meets the requirements of astm c 1177. The roof deck can be plywood metal concrete or wood planks. With this kind of roof the insulation follows the slope of the roof.
The iso is covered with 60mm tpo. However most cathedral ceilings and low slope flat roofs are insulated roof assemblies. Insulation cover boards training and education take advantage of industry leading training and education though care the center for the advancement of roofing excellence. Polyiso is an easy cost effective sustainable and energy efficient construction material.
This vapor if left unchecked can wet the insulation and over time will reduce the r value of the insulation and lead to mold. I am trying to figure out the best insulation build up under this roof situation. There s a reason polyiso rigid foam insulation is used in more than 70 of commercial roof construction as well as in many residential builds. There is polyiso over the plywood built up 1 4 12 on all four side to the the center.