How to Raise / level the Floor. Turning a Garage into Living Space Part 2 

You're very welcome. I hope it helped. Please don't hesitate if you have any questions.

Wow! Thank you so much. I needed that. Have a blessed day.

There are a lot of things to consider. Your geographical location. Topography. Are you in a flood zone? North? South? Humidity. An improperly installed moisture barrier can hold condensation and promote black mold and rot. My best advise is research your area and local building codes. Ultimately, you have to please your inspector. Assuming that you live in a state with building codes. Spray foam insulation is another consideration. It can be both insulation AND vapor barrier. I recommend checking out Matt Risinger's RU-vid channel . He is on the cutting edge off building technology and covers questions like yours in a multitude of regions. If I help a friend out in another state down south, I research what to do by watching his channel. There is no easy or standard answer, but I hope this helped.

Its free floating. But the plywood kisses the walls of the garage. Just don't forget the blocks to keep the joists from twisting or flopping over. That and the boards at either end will give you all the strength you need. Gravity will do the rest.😉

It was absolutely completely bone dry. The inspector was ok with it. The fiberglass is 2 to 4 inches above the concrete so that makes me feel better about it too. But I DO like your suggestion. 👍

I had to go up about 9 inches at the low end and about 4 inches at the high end. With it being a garage in NJ, the cement tiped toward the garage door to let rain and melting snow drain. Its probably easier if you work down from the top. Start with your finished floor hight. Then subtract tile laminate or carpet. Then subtract the thickness of what you plan to use. I used 3/4 inch plywood and 1/4 inch luan. If your porch is going to remain a porch, you might use pressure treated 2x4s as floor joists and 2x6s as decking. If you are going to make it living space, you might use pressure treated 2x6s and 3/4 inch plywood. If thats too high you might want to use pressure treated 2x4s and shim them up till they are high enough and level. Then insulate and cover with 3/4 inch plywood and carpet, tile, vinyl, whatever.

@@jimmybs awesome, thanks for the reply

You're very welcome. Glad to be of assistance. 😊

I wouldn't recommend pallets due to them not being presure treatment and having too much flex. They could also get you in trouble because building with them violates building codes. However, if you build with pressure treated lumber and you come in under the floor hight of the house, you can make the framing level with cement block, pressure treated wood and cedar shakes used as shims. If the floor is level, but lower than the house by a little bit, you can add plywood layers to make up the difference. Remember to consider the thickness of the floor covering you are going to use. You want your laminate, hard wood or carpet to end up at the same hight as the rest of the floor. Or at least very close to it.

I went with NO ventilation due to to gap being so small at the high end and how dry the cement always remains bone dry. If need be, I can always circulate air under the floor from one closet to the next.

@@jimmybs I have a sunroom that’s 20x19’ with with 9” concrete slab… and i want to make it part of my living room… thinking about using 2x8s as my joists with plywood as sub and wooden floors eventually… should i go with pressure treated 2x8 or regular will work ? Thank you for your feedback and any suggestions!

Definitely pressure treated. The cement will wick water and the wood will rot otherwise. If you can get the wood up on plastic supports, that's even better.

I chose fiberglass insulation for a 2x6 wall. The high end of the floor was roughly 6 inches. I stapled it as you would any floor, wall or ceiling. Then screwed the 3/4" plywood down over it. You can see it done step by step in my videos. Please watch start to finish for a complete step by step guide. Thank you for your comment. Good luck with your project.

doing the same project, garage conversion however concrete is so badly out of level i'm probably 8" at one corner. 2x6 frame like yours. I'm putting down a roll of this ribbed type plastic, with taped joints as i don't want moisture wicking up... and then 2x6 wall insulation over it, non paper backed, and heavy poly over joists and then 3/4" osb.. cold winters up here in Edmonton Alberta. Also running 3 heat vents through the floor 4" diameter.@@jimmybs

@@dbpool I recommend rockwool. It offers more R value. It's only a little more expensive for a project like yours. It also acts as fire stop and stands up to dampness well. Just some food for thought.