I'm finishing my attic and have just realized that my rough carpenter screwed up by not addressing a cut joist. In photo 1, you can see that the joists have been sistered with LVLs, but there is a gap in one joist around the vent pipe (lower right). The small pieces of wood connecting the two sections of the original joist are resting on top of a wall below (perpendicular), but it is not a load bearing wall. In photo 2 you can see this area up close as well as the framing for a bathroom. The room has since been drywalled and tiled.

We were about to put the toilet in, when I realized I had better be sure that corner can take the 100+ pounds it will add. I am going to set the toilet box in the corner and see if I detect any deflection over the next month or so. (I'm putting joint compound along the top and bottom of the baseboards and will watch to see if cracks form.) If I see even the slightest movement I will ask my rough carpenter to come back and address the cut joist, which will mean breaking into the ceiling of the finished rooms below.

However, I'm not sure exactly what the fix should be. Maybe sister the two sides of the cut joist, except they do not align exactly. Maybe cut off each side and and put headers connecting the two pieces to the adjacent joists? Except that the adjacent joists should be doubled, and that will not be easy--the rooms below are finished. Maybe they can be strengthened with a steel place?

joists before floor

after framing

  • 1
    "but it is not a load bearing wall" ... surprise!! It probably is a load-bearing wall now, even if it's not intended to be ... – brhans May 23 '19 at 15:15
  • 2
    I’m fascinated by the triple joist staggered sistered splice. – Lee Sam May 23 '19 at 15:22
  • I know, it's a disaster. But I need to deal with it somehow. Any advice welcome. – JCK May 23 '19 at 16:29
  • 2
    I can not see the relationship between the two photo's. I see tragic things in both but do not understand the relationship of the two. – Alaska Man May 23 '19 at 18:56
  • @AlaskaMan It took me a few minutes, but I figured out the relationship: the second picture was taken standing a few feet further to the right - looking straight on at the area instead of at an angle - and was taken further along in the construction process after the wall framing was added. If you look down into the floor in the second picture, you will see the triple-staggered splice. If you look at the first picture, you will see a black rag(?) covering the end of the PVC pipe that is shown in the second picture. – Moshe Katz May 29 '19 at 19:22

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.