# Subfloor first or framing first



## 325_man (Jan 20, 2011)

I have been looking for the answer to this question as I am in the process of finishing the basement. 

Should I install subfloor first or framing first?

Thanks


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## JazMan (Feb 17, 2007)

Subfloor, in a basement? 

Are you doing some kind of special system? Tell us more.

Jaz


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## Jason34 (Aug 15, 2010)

Only reason I can think of for a subfloor is if you are doing a raised floor. Maybe heated floors, very uneven slab or some other reason. Usually you dont need to install a sub floor in a basement


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## 325_man (Jan 20, 2011)

JazMan said:


> Subfloor, in a basement?
> 
> Are you doing some kind of special system? Tell us more.
> 
> Jaz


Nothing special planned for the basement floor. I just want to finish the basement, to add more living space. 

I was thinking to have tile flooring.


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## joecaption (Nov 30, 2011)

If the slab is flat then there's no need for a "subfloor".
I would build the walls first then lay the floor.


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## princelake (Feb 19, 2012)

if you are tiling then there is no need for a subfloor. People put subfloors in because they may have a minor leak or water problem and their flooring and contents don't get destroyed. also you dont feel the damp cold floor. i would doing your framing first then your subfloor. Do not put your framing on your subfloor. If you ever had a water problem bad enough to pull up the floor just imagine trying to tear it out with the walls on top of it.


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## jagans (Oct 21, 2012)

Normally, you lay out your walls on the concrete slab with a chalk line, then anchor a pressure treated sole plate to the concrete floor. 1/4 inch Rawl spikes are good for this. You need a decent hammer drill. I have a Hilti TE-12S that I love. You then build your walls on the floor with a plate on top and bottom. Stand them up Plumb and shim, then screw to joists or blocking placed between joists. Electric and plumbing, insulation, drywall finished and painted. then floor, then trim. Ive seen the drycore stuff, and I don't buy it. If you have a wet basement you have to fix it outside, not inside.


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## JazMan (Feb 17, 2007)

It's not a matter of if the floor is flat or just thinking it's a good idea to build a subfloor on a slab which is below grade. Someone show me the spec that says building a sleeper-floor below grade is recommended anywhere.

It can work under some situations, but wood in contact with a slab below grade is not a good idea. Plus trapping moisture from a slab can be a problem and often is. 

Jaz


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## 325_man (Jan 20, 2011)

Got it! Framing first, then subfloor next. 

Thanks all!:thumbsup:


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## JazMan (Feb 17, 2007)

Oh boy!.........:huh:

Jaz


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## woodworkbykirk (Sep 25, 2011)

if your using a floationg interlock sub floor system you have to frame the walls first. if you build the walls on top of it the subfloor will buckle


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## ryanh (Jul 23, 2008)

Always add subfloor after walls. Basement walls should be floated from the floor so keep the subfloor away from under walls so it can move if need too


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## oh'mike (Sep 18, 2009)

325_man said:


> Got it! Framing first, then subfloor next.
> 
> Thanks all!:thumbsup:


Framing only--NO subfloor at all---you have a floor all ready to accept tile---you do not need or want anything more.


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## ubcguy89 (Mar 19, 2013)

I have done this before a few times build the walls, then put sleepers if you wish. personally I would ardex the slab and lay tile


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## ccleme11 (Mar 20, 2013)

JazMan said:


> It's not a matter of if the floor is flat or just thinking it's a good idea to build a subfloor on a slab which is below grade. Someone show me the spec that says building a sleeper-floor below grade is recommended anywhere.
> 
> It can work under some situations, but wood in contact with a slab below grade is not a good idea. Plus trapping moisture from a slab can be a problem and often is.
> 
> Jaz


What if you use a 1" rigid foam and t&g ply on top for better insulation and a warmer floor?


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## drtbk4ever (Dec 29, 2008)

ccleme11 said:


> What if you use a 1" rigid foam and t&g ply on top for better insulation and a warmer floor?


I'll comment to your question ccleme11 in YOUR thread where you asked this very question.


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