Insulating flat roof with 7" cavity with roof tear-off

Hot-dry climate. Roofer removing all sheathing. Insulating from above while cavity is open. Plan for 5.5" open cell foam to the drywall and also covering dropped soffit area that houses ducts. There will be a minimum air gap of 1.5" (7"-5.5") between the foam and the deck at normal ceiling heights, about 1 ft over dropped ceilings.

Any concerns with this installation? electrical, mechanicals. performance etc?

Views: 1878

Reply to This

Replies to This Discussion

whoa didn't see all the comments until after i posted. sounds like you are on top of things. The OCF is an effective air barrier and will stop most all convective sources of moisture, and I don't believe you need to worry about vapor diffusion in that climate... So leaving the air gap sounds good to me. I'm a cold climate guy so I'd like a second opinion as well. Where's David Butler when you need him?

RSS

Videos

  • Add Videos
  • View All

Latest Activity

Brad Cook replied to Jim Tenhundfeld's discussion LED's and motion sensors
"I don't know what it stands for. See RAB.com"
17 hours ago
Jim Tenhundfeld replied to Jim Tenhundfeld's discussion LED's and motion sensors
"That makes sense since the same thing happened with dimmable CFL's.  I have never heard…"
17 hours ago
Brad Cook replied to Jim Tenhundfeld's discussion LED's and motion sensors
"My first thought is whether the motion sensor and/or the LED lamp is a cheap one. I had so many…"
yesterday
John Wagner joined allen p tanner's group
Thumbnail

Energy Auditing Equipment for Sale, Trade or to Purchase

Discuss the pros and cons of the equipment you are interested in prior to purchase. Post equipment…See More
yesterday
Home Energy Magazine posted a blog post
yesterday
Jim Tenhundfeld posted a discussion

LED's and motion sensors

When completing an audit, a customer told me that when he installed a LED lamp in his outdoor…See More
yesterday
Barbara Smith posted videos
Thursday
CharlieK posted a discussion

Eco-Cottage Program Applauded By Housing Groups, Suppliers & Lenders

AmeriSus a leading player in the eco-kit home business kicked off a new program on MLK-day which…See More
Thursday

Home Energy Pros

Welcome to Home Energy Pros – the unique digital community by and for those who work in the home energy performance arena.

Home Energy Pros was founded by the developers of Home Energy Saver Pro (supported by the U.S. Department of Energy) and brought to you in partnership with Home Energy magazine.  Home Energy Pros is sponsored by the Better Buildings Residential Network. Please honor our Guidelines

© 2017   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service