Insulating TJI garage roof

[Unregistered]

Hi, I have a free-span lean-to type garage roof supported by 14" TJI joists on 16" centers. There are existing soffit vents at both eaves. I was looking at staple-up radiant barriers but am leery of how effective it would be during Michigan winters.

Need some good ideas as to how to insulate it.

Thanks.

[Wgoodrich]

First TGIs are an engineered product. Are you istalling these as rafters meeting the engineers specs?

To insulate you need a mininmum of 2" gap between the bottom of the roof deck be it metal or wood. This air gap allows air to flow to dry out that area to allow drying of condensation in that area.

Most often paper backed fiberglass insulation is stapling the paper to teh bottom of the rafter leaving the 2" air gap between fiberglass insulation and the bottom of the roof decking.


Good Luck

Wg

[Unregistered]

Thanks for the comeback wg. Looks like it's doable.