Replacing a load bearing wall with a span?

Question

for the first floor of a two story residence - a room above the span

wondering what the standards for span are for 2x pine - I've referenced this http://newstore.southernpine.com/images/ref207.pdf site, page 16 seems to apply to my situation, but would like some info in layman terms to confirm the info

the span will be perpendicular to the floor joists above - and let's say the room is 24' wide - I want an 8' span - so I'd need two 2x12s (grade 1 or 2 lumber)
and so on for greater spans

seems to make sense

I'd like some sort of confirmation I'm figuring correctly~

Answer 1

First of all you need to make the header the same thickness as your framed wall. So you may need to add some plywood between the 2" x 12's to get it to correct wall thickness.

Next you need to make certain you have solid bearing at the bottom of the side studs that will be supporting this header. Which means you may need to add blocking between the floor and the sill plate on your foundation.

You need at least 3" of wood under each end of header for support or 2 full studs.

Construct a temporary wall back about 2' from the area you will be removing. Place a strip of 1" rigid styrofoam up against your ceiling, then install a floating wood plate under it, temporary studs 16" on center resting on a bottom plate. Put some x bracing on this temporary wall for needed bracing.

Now remove your wall all the way up to expose the top plate(s).

Put top of your header up tight against the bottom of the exposed top plate. Remember you need 2 studs cut tight to fit under the header at each end. Don't cut the old bottom wall plate out until after you install the 2 studs at each side.

Now build your header down with lumber to desired height.

Remove temporary support wall. Patch wall around new opening and trim out.

I would take out wall materials on both sides all the way up to bottom of top plate. Then patch in back in. * you know there might be wiring or pipes in this wall?

Answer 2

dogger, If you surf any web sites with similar forums or questions, they will all wind up saying the same thing---especially those sites where experts moderate the sites. You should have an engineer or expert come and look at your project. There are host of other factors beyond just how thick the beam should be. You have point load, floor support, and floor weight to be considered. You may be able to contact your country building inspectors and they can come out and give you some advice. But since your house was built in '57, that's codes that are 52 years old. Lots have changed since then. I simply wouldn't trust anyone to give me a good calculation, because they can't inspect your site and see if other factors need to be included in the equation. The last thing you want to do is have to repair a sagging beam that doesn't bear the load properly. good luck

Answer 3

Take a look at this, there's more to think about than just the beams your going to use.

http://www.rd.com/familyhandyman/content/38210/



The charts from your link appear to support your thoughts on the size of the beams. If head room is an issue, you might want to consider engineered timber frames. You may be able to use lower profile (8" or 10") instead of the 2x12. Check with a lumber yard as to which ones you might want to order.

Answer 4

Check the American Wood Council site for beam size reqd to carry loads over a given unsupported span.