Check out some similar questions!

Zemuss · Jan 25, 2011, 05:04 PM

My 1913 house has floor joists that are butted up on the main beam instead of spanning the whole length of house. There are a few where they are separated, one is nearly 4 inches gap between them. Can I "pull" them back together with large lags and washers or is there some other process for this. Thanks

Zemuss · Jan 25, 2011, 05:08 PM

More info: none of them are bolted or screwed together they just lay side by side.
Also the overlap on them is a little excessive, 6-8" on all of them. My guess is they got this way since on each one there is only 1 place that they are braced to each other

ballengerb1 · Jan 25, 2011, 06:01 PM

Spreading in which direction? Are they spreading from each other or pulling back so they aren't fully on the beam?

creahands · Jan 25, 2011, 07:23 PM

Floor joists/beams are nailed at the box beam. This is the beam that runs around the perimeter of the house.

The subfloor is nailed to the joists. In an older house the subfloor is probably 1x6 or 1x8 on a diagonal.

At mid span there would be/should be bridging. This can be either solid or X braces.This is to keep joists perpendicular.

If the floor beams are not perpendicular to the support beam/girder, then the bottom of joist can be moved to the perpendicular location and nailed to the girder. U can also bolt the joist together. The bolt should be put in about 2'' from bottom of joist.

The space to be adjusted should be done slowly. Over a period of weeks. If u try to move to fast, they may crack.

U will not be able to move the top of joist so as it rests against the joist coming from the other side of building.

Hope this helps. Let us know

Chuck

The spacing at the top has been there since building was built. It was an adjustment made by carpenters during construction.

Zemuss · Jan 26, 2011, 11:07 AM

They are spreading from each other, its 1 that has moved from the other one, its still square at 16". it is separated about 3" at the bottom and 2" at the top

Zemuss · Jan 26, 2011, 11:09 AM

I was thinking of using 2 or 3 bolts, as to not stress one spot too much as this is 98 year old lumber and its already bowed from the spreading. What thickness bolts/lags should I use?

ma0641 · Jan 26, 2011, 12:55 PM

The joists were never nailed to the main beam and the sub floor isn't nailed to the floor joists? Have the joists moved, in your opinion? Can you see dark or light marks that may indicate a previous position? If everything is parallel, they may be, as Chuck said, laid out that way from the original construction. Is there mid span blocking? If so, has that separated too? If there is no mid span blocking, I'd install some. If the subfloor is nailed to the joists, you will not be able to move the joists any closer without pulling out the subfloor or plate nails.

Zemuss · Jan 26, 2011, 01:03 PM

The joists are not nailed to the beam, there really is no subfloor in this house its just 1 layer of planks that doubles as both, and it is fastened in places but not to every joist, otherwise I can't see the whole joist moving 2-3 inches top and bott

ma0641 · Jan 26, 2011, 01:16 PM

They aren't normally bolted or screwed together, they are toe-nailed to the main beam and nailed through the subfloor. I've never seen one bolted or screwed together unless there was some other issue

creahands · Jan 26, 2011, 01:53 PM

Zemuss

Try to maintain the spacing at top of joist. Use a spacer the size of upper space and close in the bottom to plumb. I would use 1/4'' threaded rod with a fender washer and 2 bolts on each side.

When cutting rod to length u need, have a bolt on thread on each side of cut. This can be used to repair thread by taking it off.

A second way would be to use solid bridging near the girder and screw it in. The screws will hold better then nails. Use3'' #8 deck screws. Be sure to drill a pilot hole.

As Brian stated, ''If there is no mid span blocking, I'd install some.'' This will keep joist plumb and take any bounce u have in floor out.

Chuck

Zemuss · Jan 26, 2011, 03:49 PM

Thanks for the tips guys, it appears it has been this way for ages cause I can't even see a faded spot or the indent where it should/used to be. All the others are square except this one so it won't be too hard