Retrofit Pitched Roof Insulation

The performance of products and methods of fixing vary.

Retrofit pitched roof insulation.

U values normally achievable for the rafter level insulation of a pitched roof are between 0 20 0 16 w m2k depending on existing rafter depth and available space. On new build or replacement pitched roofs the ideal build up would be insulation fitted over and then between the rafters giving a big boost for airtightness image credit. When specifying the insulation for the pitched roof it is important that the thickness of insulation used achieves the required u value. Of your email interested please feel free to contact us on facebook at cp millworks business page.

First unfaced blanket insulation can be installed on top of the existing roof membrane prior to the installation of the new metal roof membrane. The existing roof s physical footprint framing system and other rooftop conditions will most likely control the new roof s geometry. Bituminous roofing felt on wood sheathing they require an analysis of possible condensation problems. The panel adds a remarkable amount of structure as well as insulation to the project.

In conjunction with the three step metal retrofit roofing process two other factors can improve the existing flat roof. This insulation can dramatically alter the energy consumption of the building by providing a much warmer hat for that building. German standard din 4108 3 dispenses with calculational approval if the room side vapor barrier has a very high vapor resistance s d value 100 m. Nb the roof insulation methods illustrated below are for general guidance only.

See http solaralberta ca pdfs harold 20orr pdf we have done several roofs this way 1. Kingspan with a flat roof this issue does not arise but the u value constraint and the amount of insulation needed is just the same. The est target u value for the rafter level insulation of a pitched roof is 0 20 w m2k though much higher values are achievable. Since older pitched roofs usually have a relatively vapor tight exterior lining e g.

We have done many roof retrofits with a structural insulated panel nail base panel. To 12 ga steel framing installed over the existing roof s framing members to create a sloped plane. There is a requirement when refurbishing a roof to have a minimum u value of 0 18 w m k in england and wales but for a complete re roof in wales the minimum u value required is 0 15 w m k. Cover the roof with 6mil poly sealed at the wall line to the vb in the wall.

The mbci nuroof retrofit roof system utilizes light gauge 16 ga. Together with not having to provide a ventilation pathway the technique permits insulation to be installed within the full depth of the rafter.