Home>Discussions>EXTERIORS>Finishing a part of the garage
3 posts / 0 new
Last post
Finishing a part of the garage

We would like to create a room in a 3 car garage by walling off about a third of it. What would be the most efficient way to heat and cool the room (about 300 Sq Ft)? We are in Southern California so winters are 40 to 60 degrees and summers are usually in the 90's.


Re: Finishing a part of the garage

You don't say what you'll be using the room for (living space, workshop, etc.) but I'll assume living space. For any air conditioned space, you need a supply and a return for the air to circulate in the room. Be sure the room is insulated where the garage door is. Easy to do. Just put up a stud wall and insulate it as you would any outside wall, with batts and a moisture barrier.

Next, you'll need to run some ducting. If you don't have an airspace above the ceiling (drywall or drop ceiling??), you'll need to build a little soffit (fake ceiling), along one side of the room. In the soffit or above the ceiling, you can run flexible duct work. Try to get the vent over towards the middle of the room so the whole room gets cooled on hot days. Check for a way to get a circulation path for the air.

Someplace in your house is a return air duct which sucks the air from the house, back through the furnace/air handler. If you are going to have a door to the room and it'll be closed part of the time, you'll just have cut the bottom of the door about 1" above the carpet. If it will be open, it may be OK on its own. If you're having heating/cooling problems, you may have to talk with an air conditioning service company who can either suggest a return air method or do it for you.

Good Luck.

Re: Finishing a part of the garage

Ya know .... I'm all for DIY projects .... but there are some things that are best left to pros.

Unless you know what you are doing I wouldn't suggest playing with ducting for HVAC.... otherwise you could cause more problems than you bargined for.

For example ... suggesting to under cut a door for the return air supply is used for small square footage spaces such as a bathroom and really shouldn't be considered for larger spaces.

just 2 cents.:)

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.