Hello. I’d like to get an opinion on what material I should use to replace an old post in my basement. The post coming out is an old tree post and supports (or did years ago) a substaintial part of the house.
Should I go with Doug Fir or something engineered? I’ve replaced a couple of these posts already and used 6×6 Doug Fir. Would I be better off with 6×6 PSL? I’ve used 4×6 PSL before, does it come in a 6×6? The house is a 1-1/2 storey ballon frame and the post is under an 8×8 timber.
Or hey, send me back to the structural engineer at the lumberyard — just looking for an opinion, it’s Sunday. Thanks.
Replies
steel
A steel jack post usually does the trick. If it is carrying an unusually large load, you might want to considers a custum steel jack post.
dave
a concrete filled lally column. $30
How about another tree? Saw down the neighbor's maple or oak when he's not looking and it only costs you the gas(sic). If the supported beam is an 8x8 what is the average diam of the existing post? If your replacement post is at least as large you should be in good order providing the previous post hadn't failed. Why are you replacing it? It won't fit in a proposed wall? I've used nailed up 2x lumber as point load posts with success under 12" and bigger parallam beams or lvl beams which where called for by engineers, making the nailed post at least as wide as the bottom of the beam. Checking with an engineer is always a good idea, worth the cost.
I concur with those who recommend steel jack-posts, but would add that you should make sure there's a footing under the slab in the area where this post will foot. If there is not, you will need to break out part of the slab, dig, and pour one. Otherwise, the load on the jackpost will eventually crack the slab and sink it.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Absolutely. I forgot about the footing for the post, just posted the reply quickly. From the sounds of it, I would guess their is no footing and one needs to be poured.
Two ways you can break out the slab:
With either method, it's a good idea to disconnect any smoke detectors in the house before you begin, and warn the neighbours that all that smoke/dust they will see billowing out of your basement windows does not mean the place is on fire.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
I'd use steel, but in ontario, the code stipulates that the top plate be 1/4" steel and the width of the supported wood member 9.17.3.2(1). Here, a wood colum has to be as wide as what it supports 9.17.4.1(1). This may not be code there, but it's a good idea.