How To Extend Roof Rafters For Insulation

Modern u value targets mean installing insulation between rafters only is rarely a viable option.

How to extend roof rafters for insulation.

2d extend insulation into joist space to reduce air flows. For instance if the roof has 2 by 6 rafters and you want r 30 insulation which is standard in many communities you can add a 2 by 4 which will give you an 9 inch rafter space. The outer ends of a roof s rafters the sloped members that give the roof its pitch provide shade divert rain and create soffit space for attic ventilation. They are directly below the roof sheathing and are were insulated with fiberglass batts stapled between the 2x4 rafters.

How to increase the interior ceiling joist for r38 insulation. 1 improve the structure of the roof and 2 allow more space for insulation. The current status is that we have 2x6 roof rafters actual 2x6 s the house was built in 1915 that are 20 o c. How to extend rafters.

The first issue is with regard to how to insulate the sloped portion of the roof. By installing high density 8 inch fiberglass batt insulation the rafters will then meet an r 30 roof insulation standard. Ceiling joists are the horizontal boards that span the width of the house resting on the outer wall plates and possibly on. There are some unfinished crawl space areas in the corners on the upper floor.

Air circulates from the lower part of the roof overhang through the rafters and out the ridge vent of your roof. The baffles will allow circulation to continue even though insulation has been installed directly in the path of the rafter air movement. I have a 1925 bungalow in michigan climate zone 5. So we need to do two things.

How to insulate 2x4 rafters.