The notching and boring rules of thumb for solid lumber are shown in fig.
Floor joist above garage.
Air seal the floor above a garage when there is living space above the garage and make sure floor insulation is in full contact with the underside of the subfloor.
The taller the joists the more room for insulation and warmth of the floor.
Can you not eliminate touching the garage floor at all and simple secure a 2x8 to perimeter walls and use joist hangers to build a deck sitting approx.
If you have an attic over your garage these joists also bear the load of your attic flooring and any materials you store in the attic.
Tji joists in garage floors.
Air seal rim joists and any holes in the top plate of the garage walls.
Building a framed wood floor over an existing concrete slab can provide the space needed for electric wiring heat venting plumbing drain lines and added insulation when remodeling a basement or garage space.
The procedure for installing a floor structure over a slab with 2 by 6 joists can be.
1 5 to 2 inches above garage floor.
The wooden joists or beams over your garage help hold your roof in place.
If you need a storage area above your garage strong ceiling joists are necessary to support the added weight.
This will eliminate the need to worry about shimming an uneven floor vapor barriers ect.
Lay the joists on edge across the width of the floor.
Floor above a garage smaller room over a large garage.
If your home is more than 20 years old your floor joists are most likely solid wood 2x8s 2x10s or 2x12s.
Seal all seams gaps and holes in the subfloor air barrier with caulk or foam.
This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction.
Insulate ducts and plumbing and put them close to the floor.
Nail cross blocking boards to hold the joists together every 4 feet.
If hvac ducts are routed through the floor assembly the floor joists must be deep enough to install several inches of insulation under the ducts.
Install either 2 by 2 2 by 4 or 2 by 6 joists over the garage floor depending on how much room you have floor to ceiling.
You can notch and bore joists without sacrificing critical strength but you must follow the rules.