Properly Repair a Cracked or Cut Floor Joist

In this video we repair a floor joist that had a section completely cut out. We used a method called sistering to add a new joist off to the side.

This repair method will work for many damaged floor joist situations.

I have had my residential builders license for 23 years.

#structural
#floor
#diy

[HomeRapidRepair]

Please share your experiences with this type of repair.

[kaylynanderson]

Thank you for your video. I have a severely cracked joist in my basement, so this video gives me good advice.

[cerealkiler]

you saved my ass but i will most definitely add extra support on my clients property . You still a Heroe

[MOAB-UT]

You should have doubled up on the other side of that cut out and at least 2 feet past the break. Always glue and screw. Use the bolts before the nails or screws. Installing a few supports in the basement is never a bad idea if you have room. Each can easily cover 3 joists using a strong support on top. Cross bracing between joists is always a good idea.

[brennickjack]

Great video, , , if you guys ever do any sagging roof rafter repairs, post it... I think I need to sister up a few roof rafters in a garage I hav

[huejanus]

I had to do this to two cracked joists in my basement, electrician drilled holes right at the bottom of the joists. I squeezed glue above the original joist before lifting, on the side and on top of the new, hopefully prevents future squeaks. Just as a side note, grk makes screws that are rated at 450lbs in sheer, 16d nails are rated at 150lbs in sheer. Although it’s kind of a moot point if you’re putting in lag bolts.

[RsinsRpaid]

I have a simular issue in an old house were a 2 ft section was cut out a floor joist. I was going to use 2 trimmers and joist hangers etc, but if I used this scabbing/sistering method you are showing in the vid will that be up to code in NC? Also if the section of jost thats missing is 2 feet. how long do the sistered boards need to be? Granted we have no peir or support to rest the boards on so they would just be sistered on both sides of the cut joist. LMK thanks!

[NewHVACGuide]

haha! "Don't worry, we'll cut that part out". No pun intended

[JoseMolina-stvk]

Would you use shims if existing joist was actual size and the replacement was nominal?

[daijoubu]

There are structural rated screws, eg GRK R4, otherwise use nails, also the sister joist should ideally be free of large knots, especially on the edge lol, don't use a piece like in this video, and make sure the jack oist is plumb before jacking, an hydraulic bottle jack may be good to have if you have multiple repairs to do or a second story, that little screw does poorly if it's loaded

[artackerman]

I would have doubled up or use a piece of steel for extra strength

[darkflux]

what you did there is not "sistering". that is a "scab". a sistered joist is the full length of the joist it goes next to. that is what makes it a "sister".