Green Building Advisor Venting Flat Roofs

When installing or repairing a flat roof you must adhere to building regulations.

Green building advisor venting flat roofs.

So much information has been devoted to the subject of roof venting that it s easy to become confused and to lose focus. 2 if you re going to vent the roof then vent the roof. So i ll start by saying something that might sound controversial but really isn t. Originally published may 1976.

Wash the underside of the roof deck with air. Part h of the building regulations regarding drainage state that water should drain to one or two edges. That means the entire perimeter of the roof needs to have air inlets meaning continuous soffit ventilation. A qualified roofing contractor will be able to advise on this but here are some of the main guidelines.

He says ruling out a layer of exterior rigid foam. If you are planning to install mineral wool insulation on the interior side of the roof sheathing you will need to include a ventilation channel between the top of the insulation and the underside of the roof sheathing. An air permeable insulation like mineral wool cannot be installed between rafters if the assembly is unvented. The flat roof overhead is framed in full depth 2x6s finished with what jordan believes is roll roofing a type of asphalt roofing.

Musings of an energy nerd. The room does not have any venting nor is it possible to vent. There must be a slope of 1 80. If you re actually going to vent the roof let s be serious about venting the roof.