Do I Need Floor Joist Hangers Subfloor

A cast iron tub with water and occupant can weigh in at more than 800 lbs.

Do i need floor joist hangers subfloor.

In buildings with basements the first level of floor joists serves the same purpose. Sometimes it s the subfloor that s the problem and not the structure under it. Sometimes the plans for a home may call for additional joists to be sistered next to the other floor joists for more strength. They are sometimes not required at the header if they rest on a nearby drop beam and you drive nails through the face of the header into the joists.

Floor joists installed on second or third or higher levels double as ceiling joists for the level below. Codes typically call for attaching joists with joist hangers at the ledger. In cases where greater open spans are needed framers often use joist hangers which are u shaped hardware pieces that are nailed in to accept hold and support flooring joists. Dropped ceiling will only support new 5 8 blue board.

But even in that situation some inspectors will want to see joist hangers. Are joist hangers needed at each. It is flexible it can be changed out it is inexpensive. 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.

In the past 2x4s or 2x6s were sometimes used as floor joists. True floor joist span calculations can only be made by a structural engineer or contractor. If you need to cut through a joist firm up the floor as shown in fig. It will update all the amounts needed but it won t take into account any joist that may have to be doubled and or beams that would need to be added because of this opening.

This method of laying a sturdy subfloor on top of joists and then topping the subfloor with a cosmetic only flooring top creates a tighter stronger structure. This size is no longer acceptable when framing a structure. The only caveat to this is that you need to make sure you have enough space to add another joist. If you re working on a floor in an older home you might want to consider adding a new layer of plywood over the decking.

Usually when a joist gets sistered the new lumber does not span the entire length of the old joist. Layering makes it easier to change the visible floor if you tire of the look or if it has become damaged. I am framing a dropped ceiling below an existing floor assembly which is 3 off level over 20. Take some extra time and jack the damaged area up so that the new lumber doesn t need to be notched.

Floor opening if there is an opening in your floor enter the sq footage in the floor opening field.