Attic Insulation in Southern Mississippi
Hello Everyone.
I have a home from the 70’s that I have been renovating slowly. Currently has blown in fiberglass insulation and looking to improve my energy efficiency.
I am looking to have my attic spray foam insulate and need your professional (and personal!) opinions and guidance to ensure I am doing the right thing.
Open or closed cell? I have been reading back and forth about which to use and no real definitive answers. Just a lot of back and forth.
Currently have soffit vents and roof turbines for ventilation.
I believe the answer includes closing the vents off to make an air tight environment.
With that assumption. Closed or open cell foam and how would you go about everything else?
I have a 6 month old A/C and a metal roof. Oh! The Roof! If/when I do this. Would painting the roof with a solar thermal paint help with keeping the heat under control? Or would that cause issues with a combo nation of the foam
-Andrew
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Replies
Of course, this is the south and local code requires the HVAC system be installed in the attic under penalty of death? LOL
Simply put moving the insulation to the roof line is only marginally better than the current sad situation and is unlikely to return your investment in the next 60 years. This is because the roof line has a much larger surface area that will lose more energy if it had the same R value as the attic floor. To make matters worse insulating at the roof line all but forces you to select spray foam insulation that is so expensive that no one ever buy as much R values as you likely currently have.
Note If you spray and fail to fully condition to more or less the same as the rest of the home by not installing HVAC registers in the attic space and removing the old insulation the risk of mold and rot is quite high.
You might consider burring your ducts in cheap fluffy insulation.
https://www.energyvanguard.com/blog/buried-ducts-allowed-2018-building-code/
Walta