Flat roof insulation
BPortnoy1
| Posted in General Questions on
Hello. My house has several areas with flat roofs. A big one is over the garage ( which is insulated and has a mini split) and then 3 other smaller areas. The flat roof is currently insulated with fiberglass insulation only. The outside layer is epdm. On the inside there is painted Sheetrock however there are holes in the Sheetrock where recessed lighting is. Would you be concerned with condensation in this assembly? I’ve read a lot about cathedral ceilings with this being an issue but not much about flat roofs. There are no vents to be clear. Thank you.
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Yes, I would be very concerned about moisture-related issues with your assembly. This article covers the topic thoroughly: https://www.greenbuildingadvisor.com/article/insulating-low-slope-residential-roofs.
Thank you. And adding vents to flat roofs isn't really an option right?
Also Do you suggest I avoid using heat from the mini split in garage during winter until I get it fixed? I feel like the temp differential will make the issue worse. Seems like only option without removing roofing is to remove Sheetrock and spray foam. Thank you