Insulating garage ceiling with 2x6 storage truss/joist

[kolky]

Hi all,

It's been a long process but my new garage is finally up (about a year after signing the contract)! I had it built with storage trusses and have flooring in the attic covering a space roughly 12'x25' (garage interior is 25x25) that will be used for storage. The joists are 22 1/2" OC and are 2x6.

I'm trying to figure out how to insulate the ceiling. Do you think I would be better with R-19 batts or with blown in cellulose? The blown in may give me a little higher R value but I'm a little concerned about the mess it may make since the area will be used for storage. The batts would work but based on the sizes I'm finding available they would be compressed a little. I plan on putting in a mini-split for heating and cooling (once the things come back in stock).

I'm in St. Louis so it gets pretty cold and hot. I'm not planning to keep it at house temps but just enough to be comfortable.

I also don't want to fir the ceiling because I need to keep the height for a golf simulator I want to put in.

 

[kaehlin]

You'll want to find a way to insulate the whole ceiling to have the biggest impact. Can you use spray foam or cut foam boards for the open space? If so, I'd just do the whole celling that way, including above the storage area. If you are insulating just the storage area, I'd probably go with bats. You'll be limited in the R-value at 6" deep with any insulation type, but it may be good enough for your purposes.

 

[kolky]

Thanks for the reply. I found some R21 insulation in batts that looks like it should fit without compressing it so I think I will just go with that. In the future I could probably lay another layer on top of it in the open areas to increase the R values there though I'm not sure how much that will gain me if the area with the attic floor is still only R21.

 

[70Beee]

I have a garage that has the 2x6 bottom truss lumber with an attic that runs the full 28’ width by 8’. I had the bottom of the attic floor sprayed with 2” of closed cell foam and the remaining void filled with fiberglass insulation before putting up the garage ceiling. The open areas beside the attic floor were insulated with 6” of fiberglass and additional fiberglass rolled out on top in the attic. I don’t heat or cool the garage yet but I have warmed it with a propane heater a few times last winter and it held the heat very well.