Updating Main Beam In Century-home: End.

bob_cntrctr

Howdy all,

New member. First post, 'cause I come across a head-scratcher.

So I'm renovating this stone century home. Foot-thick stone walls all around with the beams and even the main-floor joists buried in the stone at their ends.

Well, opened up the crappy old panelling that was nailed over the main-floor beam (that is, theone running along the first floor ceiling, that holds up the second floor) that separates the kitchen from the dining room - holy macrel Batman - this 12-foot span has been held up for decades by two 2x8's.

OK, so we're gonna beef it up, replace it with four 2x10's and sit it on proper steel posts instead of the two 2x6's currently.

So here's the head-scratcher: they sure finished these things funny long time ago. I've opened up the wall around where the end of the beam will meet the exterior wall. Drywall, vapour barrier, styrofoam board insulation - - then wallpaper over 3/16 paper board over tar-paper, THEN 1" x 12" t&g barn boards nailed to 1"x3" strapping which is nailed to the stone structure, with empty space between the straps. Haven't removed the barn board yet - I can see how it's built through some holes in boards. The barn-board is perfectly dry after a century - not bad.

The last second-floor floor-joist, the one closest to the exterior wall, is not actually connected to the wall in any way. At either end it sits in recesses in the stone, and in the middle it sits on the beam, and it "floats" about 1/4" away from the barn-board wall.

In other words, unless I take the barn board down, back to the stone, and insert the new beam into the barn-board cavity, the new beam will at best have ~1/4" between it's end and the first floor joist it supports, and neither it nor the joist will be tied at the beam's end. (End of the beam is supported by a steel post that goes down to the main basement beam - no load on the wall.)

Now, all the joists will be tied to the beam by brackets & screws, so it's not like it's going to slip off - but I've never seen this before at the end.

Anyone seen this before and have advice on the best way to deal with it? Or am I worrying for nothing - just put 'er up there butting against the barn-board, that will do it.

Thanks.

neolitic

My best advice, and I mean this sincerely,
hire someone who has a clue
about what they're doing.

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bob_cntrctr

DEAD_ONConst

Can you send good, CLEAR pictures of what you are dealing with?

Sounds as if you are just dealing with bard shrinkage, but all the same, the end-gaps are not as-designed, and therefore you should be concerned about structural integrity, assuming the beams are not resting in their pockets properly.

Pavola

"beef it up" sounds like guess work. Get specs for the beam first. Seems like you're asking what's suitable for joist bearing???? - if so bring in some other help to get it right. Pics presents info. that sometimes aren't described correctly, so post some if possible.

neolitic

Really?
Don't cha think if he went out and
ordered 'bout a half a pick-up load
of "barn-board" and a couple "proper
posts" it'd be okay?
Right?

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Jason Whipple

Why would you take out the 2 x 8's when they have worked fine for decades? Are they failing? Are they rotted? Is some building requirement mandating this be done?

I'm with Neo on this one, leave it alone. Prop up the beam with new posts and move on.

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Historic House Restoration, Cincinnati, Ohio
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A W Smith

You gotta be REAL CAREFUL with those century old stone homes. Everythings just resting in beam and joist pockets and not tied together. You could get some serious movement and subsequent collapse if you don't know how the loads are distributed in that house of cards, Your stone walls could also fall out if its only the friction of a joist holding it in. Theres no way to see this because you don't see the stone or rubble distribution in the wall. It may look solid, plumb and sound but could be eccentrically loaded.

get an engineer on site immediately before proceeding.

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http://www.awsmith.com

bob_cntrctr

Hey - some answers - cool. And thanks.

Peoples' replies strongly suggest I did a poor job communicating the situation - re-reading my original post confirms that. I think it must have been real late.

Here's the thing:

By "stone", I meant 8" concrete block.

The foundation is 12" thick poured concrete, with the 4" shelf on the inside.

Yes, the ground floor joists rest in pockets in the foundation - I have to open up the ground floor ceiling to see if the second floor joists do the same, but at least all the outside walls have been framed for insulation, and the top plate of the framing also supports the second floor joists.

Just off the centreline of the house, there is a beam holding up the second floor joists over the 12' span between the kitchen and dining room. That "beam" turns out to be just two 2x8's. The beam is supported at both ends on two 2x6's. The end at the outside wall has the 2x6's nailed to the beam and the floor. The 2x6's at the other end are nailed to the framing of an interior supporting wall. The beam is nailed to each joist it supports.

But here's where it gets really weird - Where this beam meets the outside wall - I pull off the drywall and insulation and come to wallpaper on paper-board. OK, fine, old place, multiple layers of wall. Seen that many times before. But, pull off the wallpaper and paper-board, and behind that is a layer of 1"x12" rough-hewn boards (barn board), running horizontally, nailed to 1"x3" strapping that is itself nailed to the interior of the concrete block structure. This is not left-overs of removed plaster and lathe - it was built like this.

So, imagine, at the walls of the house parallel to the floor joists, from outside-in you have concrete block, vertical 1x3 strapping, horizontal 1x12 barn board, tar-paper, paper-board, insulation & stud wall framing, vapour barrier, drywall.

So, finally, my question was: The rim joists side up against the barn board. If I terminate the new beam up against the barn board, that puts the rim joist right at the very edge of the end of the beam. For some security, I'm tempted to open a hole in the barn board and extend the beam into the cavity so it extends past the rim joist. Useful, or waste of time?

In the meantime, however, other factors have answered the question.

Incredibly, this beam and its support posts are a good 12-inches offset from the centreline of the house and from the main beam in the basement. Worse, the dining-room joists do not sit on the beam - the kitchen joists overhang by several feet and the dining room joists are nailed to them, hanging from the ends of the others. There was a thread about crazy stuff you've seen....

But - by happy coincidence, where the two sets of joists are joined, is directly over the main basement beam. Of course, there's that 4" foundation shelf protruding under the beam. Sooooo - the beam is moving to that location.

I'm going to open a vertical slot in the barn board for a jack-post directly over the basement beam. Open a hole in the main floor, and the jack-post can sit right on the beam, directly over the 4" shelf, and transfer all that load straight to the foundation.

By another happy coincidence, this will move the support post at the other end directly over a basement support post, so its load will be transferred directly to the post's footing instead of to floor joists. All those loads were ending up transferred ultimately to the same place anyway, but they were getting there through the ground floor joists and the beasement beam. For the first time since it was built, the load of this beam will not be transferred to the foundation through the ground floor joists and basement beam, and both halves of the second floor joists will be resting on a beam.

This can only be a major improvement.

Lookin' forward to some good snarky sanctimony on this one, Neo. Don't let me down brother.