Subfloor question...

[edselsouth1]

I am replacing dining room floor, from the floor joists up. I have placed 6 mil plastic on the ground. I would like to recycle about 600 sq. Ft of 3/4” x 2-1/2” oak and maple hardwood flooring as the subfloor, since that is what I have available. I will be placing 30# felt over this subfloor, then either porcelain tile (12x12), using 1/4” cement board, or hardwood. Thoughts on using the recycled hardwood as a subfloor. Thanks, David.

 

[nealtw]

No, if you want to tile, you need a good floor. what is the dimension of the joist, are they 16" on center and how long are they?

 

[bud16415]

I’m far from an expert and I understand the desire to use up material you have on hand compared to buying new. I don’t know much about tile except it needs a very stable base.


I would look at it as if the T&G was down already in an old house and flat and solid and I wanted a new floor over it I think I wouldn’t have any issue with putting another wood floor or similar over it. I have done that myself quite a few times.


With expansion and contraction and joist stability I would question the tile.

 

[edselsouth1]

Joists are 16” on center. They are full dimension 2x8, rough cut. Length is 8’4”. This part of the house was originally constructed in 1861. Thanks for your thoughts and advise.

 

[edselsouth1]

Joists are 16” on center. They are full dimension 2x8, rough cut. Length is 8’4”. This part of the house was originally constructed in 1861. Thanks for your thoughts and advice.

Joists are of oak.They tie into a main beam on each end. The beam is 10”x10”, solid oak material.

 

[nealtw]

Joists are 16” on center. They are full dimension 2x8, rough cut. Length is 8’4”. This part of the house was originally constructed in 1861. Thanks for your thoughts and advise.

That all sounds good, while you have thing open, check the bottom of the walls to see if blocking has been added between crawlspace to the wall cavity. They were left open when built and are a fire hazard and when we can we always want to seal that with solid lumber and a foam made for fire protection.

The biggest problem with tile is always floor movement and the sub floor often gets more plywood on top. I would go with a 3/4 or 7/8 Advantech. It is a T&G sheet that looks like OSB and is the best subfloor you will find.
How important is it to match other floor heights?

 

[edselsouth1]

I’ve got the matching of the floor heights already figured in. Mocked up the various components. Must have a smooth transition from dining to hallway and living room and kitchen. Wife is disabled, uses a walker, so must have a smooth transition. There is blocking and fire retardant foam. Did them when I remodeled the bathroom and hallway. Thanks.

 

[bud16415]

One question that comes to mind is why would you want a tile floor in a 1861 dining room?


What area of the country do you live in? I haven’t ran across to many homes from that era framed in oak, and oak was an abundant wood around here.


I take it there isn’t a basement below this room?

 

[edselsouth1]

Opinions on Wonderboard Lite? Seems flimsy to me, not enough structure to help in firming up the base for tiling..

 

[bud16415]

Is there cross bridging between the joists?

 

[edselsouth1]

Opinions on Wonderboard Lite? Seems flimsy to me, not enough structure to help in firming up the base for tiling..

No basement. Just a shallow crawl space...about 8 -10”. Most of the joists are resting on limestone rock in at least a couple of places. Not going anywhere. Been there for over150 years.

 

[edselsouth1]

No basement. Just a shallow crawl space...about 8 -10”. Most of the joists are resting on limestone rock in at least a couple of places. Not going anywhere. Been there for over150 years.

There is cross bracing of the same material as the joists. All true dimension lumber. I’d hate to have to add that. Would have to drill each place a fastener would need to go. This lumber is rock hard.

 

[mabloodhound]

If you are really dead set on tile then you need a plywood base, minimum of 3/4" as Neal suggested, otherwise your tile will fail within a year as the recycled boards will have too much flex. AS for Wonderboard, some tile installers don't use it and set right on the plywood. Talk to your tile installer and see what he says.

 

[edselsouth1]

If you are really dead set on tile then you need a plywood base, minimum of 3/4" as Neal suggested, otherwise your tile will fail within a year as the recycled boards will have too much flex. AS for Wonderboard, some tile installers don't use it and set right on the plywood. Talk to your tile installer and see what he says.

I’m going to glue &screw 3/4” ply ove:r the recycled hardwood. I am going to use 1/4” cement board, probably not Wonderboard Lite. The original stuff has always worked well in the past.

 

[slownsteady]

If the old hardwood still has a finish on it, tile will not stick. The plywood or Hardieboard is a better idea. If the hard wood is in good shape, sell it.