Sistering To Repair Improperly Notched Floor Joists

How to sister a floor joist.

Sistering to repair improperly notched floor joists.

Then attach the sister joist using three 16d common nails driven every 16 in. A failed joist may minimally lead to a sagging floor or in extreme cases the collapse of a home. In situations when sistering damaged floor joists with lumber of similar dimensions it can be easy to notch and slide the sister board into place. A hole is often a round or square opening fully contained on all 4 sides within a joist.

But it s usually best to run the sister joist over the entire span. Doing so strengthens weak joists and can help straighten sagging joists. Floor joists constructed from large dimension lumber bear the weight of the structure above so notching them isn t recommended. However doing this does not fix the slant that the floor has taken since the old joists got damaged.

When the sagging joists are level apply a generous bead of construction adhesive to the existing joist. How to repair notched floor joists. Driving 16d common nails in old hard wood is difficult. Framing lumber is the typical.

A notch is generally a 3 sided cut in the joist where the 4th side is open at the top bottom or end of the joist. Her floor joists were notched by someone installing electrical cabling in the middle of the span on the bottom of the joist. Take some extra time and jack the damaged area up so that the new lumber doesn t need to be.