[thehvacguy]

I'm in a 50 year old single story brick apartment. The floor caved in because the builder didn't use pressure treated lumber next to the concrete. I'm gonna tear the whole floor out and re do it. I have a few questions... Do I need to anchor the 2 by 6 to the foundation or is it ok to let it sit there and just attach of to the floor joists? Also is it ok to toe nail the floor joists or do I need to use joist hangers? Also can I use osb on top or does it need to be plywood? Thanks for the advise.

 

[joecaption]

I'm in a 50 year old single story brick apartment. The floor caved in because the builder didn't use pressure treated lumber next to the concrete. I'm gonna tear the whole floor out and re do it. I have a few questions... Do I need to anchor the 2 by 6 to the foundation or is it ok to let it sit there and just attach of to the floor joists? Also is it ok to toe nail the floor joists or do I need to use joist hangers? Also can I use osb on top or does it need to be plywood? Thanks for the advise.

#1 Why are you doing this and not the property owner,
Since no one here can see what it is your suggesting hard to suggest ways to fix it. Need some pictures.
Unless your running those floor joist a few ft. 2 X 6's will not work.
Use joist hangers.
Use Advantec subflooring with constrution adhesive on top of the joist. Use ring shank ACQ approved #6 nails. The nailing pattern is right on the sheets. Advantec is far more stable and moisture resistant then plywood.

 

[oh'mike]

A little better description will help

how was the original floor built? Treated lumber was not invented when that house was built---what allowed water to get to the old floor structure?

Better description and we will help with some ideas.

 

[thehvacguy]

My dad owns the apartment complex and he is a slumlord. He wants to just patch up this corner bit the whole floor is sinking and I wanna lay heated tile. I built a few houses so I have an idea how to fix it I just don't know everything I need to know, I'm an HVAC guy not a framer. These are true 2 by 6's spaced 24 on center. I was thinking I can lay pressure treated 2x6 flat kinda like a bottom plate on the edge of the foundation, and one upright next to the foundation. I forget what the word is but it would go perpindicular to the floor joists. The room is 12'x10'. I figure I should only need 8 2x6's plus the pressure treated on the sides. All the walls have a concrete footing under it so it is pretty solid, only the floors are sinking cause the wood is rotted out... Moisture got in cause the dirt outside the building goes above the top of the foundation plus it wasn't properly sealed on the outside, not to mention the few feet of snow this place keeps every winter. I plan to level out the outside and make a patio so that should help. I'm not loaded with cash so I need to know the cheapest way to fix it right. I'm gonna live with plywood on my bedroom floor til I save up for the heated tile.

 

[joecaption]

You can forget about tiling with floors built that poorly.
Spans to long for that size joist, spacings to far apart.

http://www.the-house-plans-guide.com/joist-span-tables.html

 

[thehvacguy]

You can forget about tiling with floors built that poorly.
Spans to long for that size joist, spacings to far apart.

http://www.the-house-plans-guide.com/joist-span-tables.html

What are you talking about? The span is only 10 feet and at 16 on center that's just fine...

And don't say "forget about tiling" if I need to get a Damn permalam beam under my floor I'm getting my Damn tile. Nothing is impossible in construction. That's why I do it

 

[thehvacguy]

Just to clarify, I am demoing the whole floor cause the whole room is sinking

 

[oh'mike]

I'm not sure how you will do this--the house needs to be lifted up a couple of inches---then slip in the new PT sill board---

 

[md2lgyk]

Your profile says you're in Los Angeles. Since when does it ever snow there?

 

[gregzoll]

50 years ago, they would not have been using Pressure treated lumber.

 

[oodssoo]

Suggestion:

Just tear out the subfloor first and see what the problems truly are. To get the floor covering you want, you will definitely need to strengthen the frame. At the moment, you stated the frame is on 24" OC. You could look into the option and frame your floor on a 12" OC. This will definitely be a whole lot stronger and will allow you to have the subfloor leveled...

Just a thought...

 

[joecaption]

Any joist, rim joist closer then 18" to the ground will need to be pressure treated, so engineered joist or LVL's are out.

 

[thehvacguy]

I tore out the sub floor and saw that half of the floor joists were completely rotted. I pulled them out effortlessly with my hands. I just re framed the floor and stuck the floor joists going in the opposite direction so they were only 10' long. I have not updated my profile, I am in Idaho now. I did only use pressure treated on the rim joists because they touch concrete, but I did not know about the 18" deal. I should get at least 5 years out of this floor I'm sure. If it caves back in I guess I will need to dig out the dirt to get that clearance...

 

[joecaption]

May be to late now but there also should have been a 6 mil. vaper barrier layed down on the ground before the joist went in.
If not someones going to be back in there again.
You did use joist hangers, right?

 

[thehvacguy]

May be to late now but there also should have been a 6 mil. vaper barrier layed down on the ground before the joist went in.
If not someones going to be back in there again.
You did use joist hangers, right?

Yes I did use joist hangers, but I didn't think about the plastic. I have been seeing that a lot on jobs up here. How exactly does that work/ what does it do? How does moisture travel upwards from the ground where we need to put vapor barrier on the dirt???

 

[md2lgyk]

How does moisture travel upwards from the ground where we need to put vapor barrier on the dirt???

Uh, it's called evaporation.

 

[md2lgyk]

How does moisture travel upwards from the ground where we need to put vapor barrier on the dirt???

Uh, it's called evaporation. Where I live, a crawl space vapor barrier is required by code.

 

[joecaption]

It's required here to.
It's the main reason that floor failed.
Moisture cause fungus to form. Fugus eats the cellulos in the wood, onnce it's gone the wood falls apart.

 

[tjbingha]

Joe,

In reading this, I have a crawl space in a newer addition where there is no vapor barrier. Is this something that is just more or less placed down on the dirt? What would be the best way to ensure that no moisture gets through sides where the moisture barrier contacts the foundation?

Thanks,

Tom

 

[joecaption]

Depends on how bad it is under there. Some areas are just dryer then other's.
Lots of times the area was never back filled under the addition so it's now lower then the outside grade once it's been graded. No gutters, or no one took the time to seal the outside of the foundation before back filling.
It's suggested to run the plastic up the foundation, and use constrution adhesive to hold it up.
You can stake it down with 16" insulation hangers bent in half.