3" insulation in garage, will more help?

[Mike K]

Hello, I have a 25 year old house with a garage under some bedrooms. It has 3 inch insulation. Am I leaking cool air from above? Will adding more be noticeable? What are newer built homes using? Thanks mike

 

[Dayanara]

With just 3 inches of insulation under the bedrooms, youre probably losing some cool air or letting heat seep in from the garage. Most newer homes use way more, like R-30 or more, which really helps with energy efficiency. Adding more insulation should definitely make a difference, especially in keeping the upstairs more comfortable and your ac from working overtime

 

[Mike K]

Yep, garage is way cool.

 

[RidWan]

Adding more insulation will definitely help keep your upstairs cooler and cut down on energy bills, it's one of those upgrades that's easy to notice once done, especially during hot months

 

[Mike K]

Went and bought 2 rolls of 3 inch 13r. 31 feet /roll for about $30. About have half the garage Improved. Hard to quantify the affect. The concrete floor is 74. The under side of insulation is 75 and gets warmer as you move toward garage doors. Upstairs floor is 76 to 77. Maybe the upstairs room will hold the cool AC in longer now. These 2 rooms over garage are always warmer than the rest of house.

 

[RidWan]

That's really solid improvement for $30 in materials and the upstairs rooms holding cool better is probably the biggest win there.
How are you attaching the insulation to the ceiling? I don't think I can see that too clearly

 

[Vertesol Eustache]

Hello, I have a 25 year old house with a garage under some bedrooms. It has 3 inch insulation. Am I leaking cool air from above? Will adding more be noticeable? What are newer built homes using? Thanks mike

Yes, you are likely to lose a lot of heat/cool through that floor at only 3" of insulation, and particularly above a garage. The comfort level could improve significantly by increasing the insulation and air sealing. Most newer homes will have very different, and higher, R-values there than were common a quarter century ago.