Retrofit Insulation Pitched Roof

Roof covering insulating a pitched roof between and below the rafters is a very common roof insulation choice particularly for retrofit and refurbishment projects.

Retrofit insulation pitched roof.

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. See http solaralberta ca pdfs harold 20orr pdf we have done several roofs this way 1. Retrofitting foam insulation on a roof recommended reasons for removing a roof s shingles. Cover the roof with 6mil poly sealed at the wall line to the vb in the wall.

Together with not having to provide a ventilation pathway the technique permits insulation to be installed within the full depth of the rafter. The use of metal retrofit roofs allows the flat roofed buildings to undergo a transformation into a sloped roof building. The natural flow of rising heat and the more exposed position of a building s roof to the elements means heat loss is prominent through uninsulated roofs so roof insulation is an important consideration in. How to retrofit a roof with insulation in my humble opinion i believe the only way to effectively and cost wise to solve the problem is to insulate from the top.

Gable end detail overhang cut and then rebuilt to hide the thickness of the over roofing rigid insulation. 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. Breather membrane in colours u value target. 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.

Installed a new fully adhered membrane to the top of the old board sheathing prior to adding all that rigid insulation. Another key advantage of specifying a pitched roof is the ability to provide a very high level of thermal performance in these roof types whether you re looking to insulate at joist ceiling level for a cold pitched roof or at rafter level if a living area within a warm roof construction is desired. 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. When specifying the insulation for the pitched roof it is important that the thickness of insulation used achieves the required u value.

Roof edge detail overhang extended to hide the thickness of the over roofing rigid insulation. These new roofs can be either low sloped less than 2 12 functional roofs or high pitched greater than 2 12 architectural roofs depending on the expectations of the building owner.