what we did in a house in Wayne PA was to jack a joist a little bit and then sister to it.We started where the joists sit on the edge of the foundation. We didn't use the same size. I think these were 2x8 and we added 2x6 and made the bottoms flush. Yes, that has the floor above sitting on the extra of the 2x8, but bolted together it's still 4x and is so for 90% of the beam. We started at every other and that was enough.
On Sat, 3 Oct 2009, Dale Leavens wrote: > Hi, > > It is too wet outside to do any work and I am contemplating a problem I have > had since moving into this old building. > > The original house has floor joists rough sawn but only 2 by 8 on 24 inch > centers. We have a springy and uneven floor. Some of it is also because at > some point one of the heating systems required framing in a big cold air > return and they clearly didn't shore up the floor when cutting that joist, > someone long since removed all of the cross bracing. > > I don't see sistering or adding joists in the usual way because of plumbing, > wiring and duct work and I don't want to add more posts and beams. It > recently struck me though that I could build in place an open web joist, jack > things temporarily up then fix the lower cord. This lead me to think perhaps > a better way might be to jack tings up just a little above the desired point > then apply a web of strap steel to either face of the existing joists on the > diagonal. A series of 'V's so that the diagonal essentially forms triangles. > This would allow me to continue to respect wiring. > > More stiffening might be achieved by running a length of angle iron along the > top inside corner against the floor and the joist and run a bolt through it > and the straps and similarly at the bottom of the joist, I wonder how much > would be enough and how much too much. At some point it might be better to > fabricate individual steel webbed joists and fit them between the originals > but then they may serve the purpose of lifting the originals which would > continue to be pulling down after nearly a century. > > Just kicking around ideas. I would like to preserve as much open space there > as I can. > > I don't have reasonable access to engineering or architectural services. > > [Non-text portions of this message have been removed] > >
