cmerk16

I am putting a pool table in my living room and it will weight close to a 1000lbs. I was going to sister plywood strips to the existing joists to strengthen them. I had a bunch of 1/2 inch sheets left over. However everything I read suggest 3/4. Do I necessary need to put down 3/4 or can I get away with 1/2? I have seen too that they put two layers of 3/4 up to make an 1 1/2" to match the existing joist. I thought of just putting three layers of 1/2 (making it 1 1/2) in since I have a bunch of sheets leftover. Can someone tell me if this doesn't make sense structurally? Otherwise it's a easy way to save some money.

Thanks

AndyGump

You MIGHT be stiffening the joists with this scheme but you will not be strengthening them. If you could install new joists right along side the existing ones (sistering) that would strengthen the joists and stiffen things up. No code violation either.
Do you have that much access for the joists?
Are they first floor joists and you have a basement or crawl space under the floor?

Andy.

nealtw

Like Andy said all the weight will be on 2 joists and they should be doubled up and I would still use the plywood as you suggested to take the bounce out of the rest of the floor.

CallMeVilla

Plywood will NOT add strength. How big are the existing joists? If you are working off 2x10, you can double them up by using construction adhesive (PL Premium) and nailing generously. I would look into double metal joist hangers at each end too to tie the load into your framing or cinder block.

cmerk16

I saw Holmes on homes do it. So I wanted to see what others had to say. Their 2x10 joists

CallMeVilla

Holmes is my hero . . . but he did it to cure bounce from a live load of party guests. You are talking about a dead lload of 1,000 pounds. Why take the chance for a little extra joinst wood?

cmerk16

True. Then here is my next question, do I double up on the joist where the legs land? or do I double up on every joist that falls under the table.

CallMeVilla

Honestly, I would double the joists under the table plus I would add blocks between the joists all under the table. This would not only strengthen the carrying capacity of the floor but it would distribute the weight load over the entire area. This is basic structural insurance against anything nasty happening such as a friend ending up in the corner pocket.