Do I need insulation?

[jtdavies]

Last year I added a workshop on to my house. One short side is against the house, one short side fully exposed. One long side is is fully exposed with two windows and a door, the other long side is under grade. The ceiling is fully insulated and above it is my office and a breakfast nook.

I'm going to cover the long wall that is under grade with OSB so that I can put up French cleats. The OSB is leftover from construction.

OK, enough background. I'm putting up pressure treated 2x4s that will be attached to the cement block on the under grade wall as studs and attach the OSB to the studs.

In winter the room stays about 45-50 degrees with out heat. I can get it comfortable with a kerosene heater. So far, this very hot summer the room is a very pleasant 60 degrees without AC.

Should I bother insulating between the studs with some rigid insulation? It seems to be close to perfect as is. Would insulation make it "perfect-er"?

 

[Toomanytools?]

Most heat loss will go up, if one wall is southern of gets more sun you might insulate that. Rigid isn't that high in R value the pink 1 inch is only like R5, rolled batts for 2x4 will give you R13 and is cheaper than rigid. The cost of insulation will be made up in the savings of energy used to heat or cool down the road. The side that is under grade should maintain a cool temp in summer and warmer in winter so I guess you could argue the cost there. How big is the space and are you looking for any sound deadening?

 

[jtdavies]

The ceiling is already well insulated because of code requirements. The addition is 20x28 and two stories.

Thank you for your help.

 

[Fixin'Stuff]

Would you load a bunch of drinks into a cardboard box to keep them cold for a summer outing? They'll stay at a much more reasonable temp if you put them in a properly insulated cooler.

Insulation will make the space more comfortable and cost less to heat or cool. You pay for insulation once. It saves you money forever.