Supporting Cut Floor Joists

But larger is not always better when builders are constructing a home or adding a room addition.

Supporting cut floor joists. The extra two inches of vertical distance when a floor is framed with 2 x 10 joists rather than 2 x 12s can be quite important for example. The joist support helps reinforce the floor so it can handle the weight load it needs to. Then set new joists same height as existing ones alongside the old. If your home is more than 20 years old your floor joists are most likely solid wood 2x8s 2x10s or 2x12s.

Even worse is that over time any rot or decay from moisture that these cut up joists see. Tack a beam under the sagging joists. The notching and boring rules of thumb for solid lumber are shown in fig. Cutting and or removing joists to provide an entry or access can be the most difficult part of the overall project.

Supporting floor joists with joist hangers. Adding joist hangers to old joists is a good preventative measure to beef up the structure of your home. Things might work out for a while but you will have a high likelihood that the floor will flex and your tile will crack. This house was built in 1863.

In order to maintain the support integrity of the ceiling or floor joist or rafter system it is important that if joists are cut that the load that was bearing on those joists be transferred to a modified support system. Note the photos show a recent bathroom remodel where we relocated the tub drain across several floor joists. Follow the rules to keep your floor solid. Common sense tells you that large floor joists can carry more load and spacing joists closer together also increases the load bearing capacity of a floor.

Back then there was a lot less furniture and heavy appliances to add to the dead load on floor joists. The worst thing is when new homes or poor remodeling jobs end up with joists that are cut to fit the pipes and no repairs are ever made. The floor system is 2 10 joists spaced 12 inches on center. We cut out and doubled up a header where the tub p trap was to be installed.

Set a hydraulic jack and post under the beam and jack up the joists about 1 8 in. You can notch and bore joists without sacrificing critical strength but you must follow the rules. Nailing two 2x4s together will work to span about three joists unless the sag is under a weight bearing wall. This is especially true if you are planning on getting a grand.

It is very easy to over cut the notches and remove the waste in two swift cuts but over cutting the notches in this manner weakens the structural integrity of the replacement lumber. In some cases additional joist supports will have to be installed before there can be extra heavy objects on the floor. A day until they re level.