Wood vrs Steel post beam support

mschmit · 12-30-2008, 06:52 AM

Bought a 150 year old Victorian where the main house beam is supported by brick and mortar posts that are crumbling. I'd like to jack up the beam and replace the 3 existing support structures. 2 questions … after I put in a proper 12x12 foundation, is a steel support better than a wood post (existing span is about 8 feet currently supporting a 2 story structure with converted attic … existing beam is 10x12). From what I’ve read on this forum already, a 6x8 solid post would work. No idea what size steel post would work. And as far as a steel post, would the adjustable 3” units sold at Home Depot work (they support 8000#). And along that same like, could I use 2 of them for jack posts to lift the beam for the initial demolition?

triple D · 12-30-2008, 11:55 PM

I dont like to see metal under houses, just in them. Some may disagree, but oh well. How old is the wood beam? ya, I would use wood, a 6x6 will work fine. It does not have to be pressure treated, but I always throw a rip of roofing paper under it. Make sure you pour concrete on flat hard dry dirt. Pour in a cardboard, or homemade plywood footing. Should be 10" thick, and at least24x24" wide. Should put in a little re-bar. Maybe a 14x14" square at mid height in pour. You could sink a simpson bracket in concrete to mount post to, or if your not expecting an earthquake, just set it on block, and nail or screw to underside of beam. I typically raise beam 1/4" and cut post to fit tight, then drop it down and move to next one. An automotive bottle jack should work fine. I'm rambling again, good luck .......

glennjanie · 12-31-2008, 10:07 PM

Welcome Mschmit:
The wood post will work, howver, make sure you have full bearing for the wide beam, putting the post in the center and use a 6 X 6 block as long as the beam is wide. Two of the basement jack posts will work to raise the load temporarily and there should be a footing below the old posts. If it hasn't sunk over the years, I wouldn't expect it to now.
Glenn