# Anyone added or upgraded insulation in attic/home?



## ZachUA (Dec 28, 2018)

We have blown in insulation in our attic, but there are places where it could use more. Then of course in researching local companies I come across some offering spray foam insulation, which looks interesting.

Any opinions on either choice?

Can you have spray foam installed between the roof rafters _and_ have blown-in insulation on the floor between the ceiling joists?


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## dfw_pilot (Jan 28, 2017)

My wife and I upgraded the blown-in insulation in our old farm house in Ohio many moons ago. We bought the cellulose from Home Depot and they give you the blower rental for free. It's hot and nasty work, but rewarding. Make sure if you blow it in, you buy those little foam pieces that go between the rafters that allow the eave vents to continue to get air. If you cover over those vents, it will cause problems.

Someone else can chime in on the spray foam, but I don't believe you want both. The foam encapsulates the home and doesn't require insulation on the ceiling if it's up between the ceiling rafters. Foam was in vogue in the DFW area, but some builders don't like it because it causes concerns, like early detection of roof leaks, etc. In the south, I'm a fan of blown in insulation above the ceiling and combining it with radiant barrier above the rafters.


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## adgattoni (Oct 3, 2017)

If you use spray foam under the roof decking, you will want to check the warranty on your shingles. If you don't have a radiant barrier on your roof decking, it's likely to melt out the shingles and will void your shingle warranty. Also, if you go with open cell foam you will also need to apply a fire retardant to the foam after it cures. Closed cell is fire retardant but open cell is pretty flammable. If you want to go with foam, installers get deals on the materials, so it'd probably only be a small premium above DIY to have someone do it for you.

They typically advise removing the old insulation if you encapsulate the attic. That would definitely be a job for a pro (i don't think a shop vac will do the trick).


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## FlowRider (Apr 7, 2019)

Radiant Barrier Foam Sheathing on the roof as insulation under shingles.

Blown white fiberglass on floor of attics/ceilings of second floor rooms.

Also insulated garage walls and blown white fiberglass in garage ceiling.

Open soffits all around with roof vents on each roof section.

Could add extra blown white fiberglass insulation if needed but so far code required R factors have worked well.

I plan to add more white blown fiberglass insulation in a few years to supplement what is already in - raise six inches to twelve on ceilings.


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## testwerke (Apr 4, 2019)

I subscribe to Matt Risinger's channel on Youtube. Always has great tips. He recently made this video.

https://www.youtube.com/watch?v=1BcqeQJqp08


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