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.

Green building advisor venting flat roofs.

So i ll start by saying something that might sound controversial but really isn t. Musings of an energy nerd. Venting of flat roofs. Part h of the building regulations regarding drainage state that water should drain to one or two edges.

The room does not have any venting nor is it possible to vent. When installing or repairing a flat roof you must adhere to building regulations. Wash the underside of the roof deck with air. Originally published may 1976.

An air permeable insulation like mineral wool cannot be installed between rafters if the assembly is unvented. 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. If you re actually going to vent the roof let s be serious about venting the roof.

There must be a slope of 1 80. A qualified roofing contractor will be able to advise on this but here are some of the main guidelines. Venting in building construction as a technique of cooling by air flow and of controlling or removing moisture has been in use for many years. A vented attic where insulation is placed on an air sealed attic floor is one of the most underappreciated building assemblies that we have in the history of building science.