I need to remove three existing 2 x 8 floor joists in my 90 year old home. All three of these in question have been trimmed down to less than 6 inches as well as having multiple penatrations from plumbing pipes. I have complete accress to them from the basement.
I want to completely remove these joists rather than just sistering and thought to install metal plate connected floor trusses. I will be installing all new plumbing and HVAC runs through this area, hence my thinking on MPC russes.
First question is are MPC trusses better than I-Joists in this case?
Second, once I remove the existing joists and install the new, how would I attached the new joists (trusses) to the above subfloor? There is old oak flooring on the finished floors above and I would prefer to leave this undistrurbed if possible.
Replies
If you go with the trusses, I would think you could screw through the top cord with screws of carefully chosen length, being sure to get ones with appropriately partial threads (smooth for most of their length), or to pre-drill oversized holes through the cord.
Otherwise, there are available aluminum "squeek stopper" blocks that are placed alongside the joist and permit screwing into the joist and subfloor. These are fairly expensive, though.
Also note that any replacement joist will shrink slightly for the first 5 years or so, so any attachment scheme should be chosen to permit you to tighten the fasteners after a few years.