Stiffening Subfloor

PeoplesElbow

PeoplesElbow

Well-Known Member
My floor is a bit bouncy as I walk on it past certain parts of my house. It is definitely in the center of the unsupported sections of the floor joists. I am thinking of making what is called a strong back on the joists as it will take the least amount of lumber (because I have to drag it into a crawl space in install it). Has anyone else done this?

I also read about wrapping a continuous steel strap around each unsupported section of the floor joists, has anyone done this?

I think the easiest would be the strong back, the steel strap might be easy to do on some of the joists but not all of them due to ductwork, plumbing etc. That and it has to be tight to begin with and I'm not sure that will be that easy to do on my back with 2ft of space to work in. The upside is not having to drag alot of lumber in the crawl space.

http://www.finehomebuilding.com/how-to/tips/floor-joist-reinforcement.aspx
 
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GURPS

GURPS

INGSOC
PREMO Member
interesting ...

a roll of strap iron, a box of 1 5/8 coarse dry wall screws and a screw gun ....


the crawl space part sucks ... let me thing, who hates spiders the most, that can help :whistle:
 
Vince

Vince

......
For a crawlspace take some cement blocks and lumber and make a pylon under the weak spot. I've done it in two places in my crawlspace. One for the refrigerator and the other for a very heavy gun safe.
 
N

nutz

Well-Known Member
PeoplesElbow said:
My floor is a bit bouncy as I walk on it past certain parts of my house. It is definitely in the center of the unsupported sections of the floor joists. I am thinking of making what is called a strong back on the joists as it will take the least amount of lumber (because I have to drag it into a crawl space in install it). Has anyone else done this?

I also read about wrapping a continuous steel strap around each unsupported section of the floor joists, has anyone done this?

I think the easiest would be the strong back, the steel strap might be easy to do on some of the joists but not all of them due to ductwork, plumbing etc. That and it has to be tight to begin with and I'm not sure that will be that easy to do on my back with 2ft of space to work in. The upside is not having to drag alot of lumber in the crawl space.

http://www.finehomebuilding.com/how-to/tips/floor-joist-reinforcement.aspx
Click to expand...

There's a couple of ways to tackle the problem. Are the joists deflecting or just the flooring between them?

http://www.prosalesmagazine.com/pro...fix-a-floor-deflection-in-an-existing-floor_o
 
PeoplesElbow

PeoplesElbow

Well-Known Member
glhs837 said:
I see this......

http://www.finehomebuilding.com/how-to/qa/correcting-bouncy-i-joist-floor.aspx

Me, I vote for a beam. Spreading the load along several joists will lessen the bounce, but sending that load down into the earth will remove the bounce completely. Strongback is a halfway measure, IMO.
Click to expand...

The good thing about the strongback is that if it by itself isn't enough I am making it so that it will be asy to add supports down to the ground. I am trying to keep from making my crawl space any harder to navigate. Had the heatpump replaced a couple years ago and the inside part had to be dragged through the crawlspace to the opposite corner of the house, right past where these supports would go.
 
PeoplesElbow

PeoplesElbow

Well-Known Member
glhs837

glhs837

Power with Control
PeoplesElbow said:
The good thing about the strongback is that if it by itself isn't enough I am making it so that it will be asy to add supports down to the ground. I am trying to keep from making my crawl space any harder to navigate. Had the heatpump replaced a couple years ago and the inside part had to be dragged through the crawlspace to the opposite corner of the house, right past where these supports would go.
Click to expand...

Well, the nice thing about a beam is that you can span your supports pretty far out, depending on the beam size you use. Remember, it's an assist piece, not the sole means of support, so span tables not such a huge deal. Putting two piers up six feet apart to allow access through them for such a maint action, with a 4x4 over them would probably make things right. Thats solution keeps you to the same depth as a 2x4 strongback with a massive increase in rigidity. I will note that if you could swing a 4x6, that almost triples your load capacity, meaning you could all do the hokey pokey in unison. Of course, a lot of this is driven by how big the room is, what size joists are in there.
 
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