Looking for insulation help in climate zone 2, Houston
Hello!
Gutted a 1950’s ranch style home in Houston, and am looking for advice for insulation.
About the house:
– removed the original gyp sheathing and brick, and resheathed with OSB/Tyvek and placed new brick
– Did a so-so job sealing up where we could with Lexel, and poly seal
– Redecked the roof
– Sealed up the attic ventilation and soffits
– HVAC system is a variable speed/communicating thermostat system with a register in the attic
Because of budget, we had to value engineer down our insulation plan. This is what I’m thinking:
– Roof Deck: 1.5″ CC + 3.5″ OC. Rafters will be covered in OC.
– Walls: 3.5″ fiberglass batts
If I’ll be placing fiberglass batts in my walls, am I losing enough efficiency to the point where I might as well not go the spray foam route up at the roof deck? In other words, is there a significant benefit in just spray foaming the roof deck, and not the walls?
Thanks for reading! Any advice/insight would be appreciated!
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Replies
I know you are in the south and ductwork in your attic is a long family tradition (LOL) but consider saying no to the silly idea. If at all possible, make the room below the ceiling for your HVAC system or go ductless.
The conditioned attic is only marginally better than the very bad idea of leaky ducts in a vented attic. The conditioned attic all but forces you to select spray foam insulation that is so very expensive that installing the code required R value does not make economic sense.
Another option is buried ductwork.
https://www.energyvanguard.com/blog/buried-ducts-allowed-2018-building-code/
Walta