Southern Yellow Pine vs Dri-Core

[Glenn Samuels]

I have a new workshop (about 900 sq. ft) and it is on a concrete slab. I'd like to use some sort of a wood floor. I was speaking to a man who owns a mill locally and he can get me SYP for 50 cents a board foot. I was thinking of using 4/4 thickness. It would be air dried and in the 12% - 15% moisture range. I can also get it tongue and grooved for an additional $.25 for board foot. I realize that I would need to put a moisture barrier down first.

First question: Is a range of 12% -15% moisture too moist and will I see considerable shrinkage?

I am also considering Dri-Core which comes in 2' x 2' squares. It comes out to approximately $1.75 per SF.

I can use some opinions on the options below and any suggestions.

[Peter Kelly]

You might give this a read: http://www.sawmillcreek.org/showthre...ion-Experience

Delta FL > OSB/Plywood > Top With T&G SYP. I wouldn't advise attaching SYP planks directly to the slab.

[Andrew Fleck]

I wouldn't put wood down on a concrete floor unless I built a subfloor on top of it using PT 2x. Some people will tell you that you can do it just using some sort of plastic as a moisture barrier, but in my experience that will eventually fail.

[Thomas Canfield]

Ditto what Andrew said. A moisture barrier against the concrete, and then PT 2x also allows being able to run conduit in the 2x space to get electrical out to the middle of the floor.

[Glenn Samuels]

On the PT 2x, what should the spacing be? Would you lay a moisture barrier down, then the PT 2x screwed to the concrete?

[Andrew Fleck]

On the PT 2x, what should the spacing be? Would you lay a moisture barrier down, then the PT 2x screwed to the concrete?

If it's your shop floor I would go 16" on center to better support the weight of your machinery and any unforeseen future machinery. I wouldn't screw at all, just get a Ramset or something similar to shoot nails down. That will be 10 times faster than screwing. You are basically building a subfloor with sleepers and 3/4" ply. Then put whatever wood floor you want on top of that. This will elevate your wood floor above your concrete allowing moisture to escape.

[Kevin Gagne]

I used the Dri-Core product in my workshop and think it is great. Makes the shop warmer and more comfortable. I haven't had any problems with machinery on the panels. I would definitely recommend them. Fairly easy and quick to install.

[peter Joseph]

I have a really small shop with very low ceilings (7ft) and posted here some years ago RE: how I might install an oak floor without losing to much headroom. I got a ton of great advice and ultimately went with OSB pl'd and nailed to the concrete and covered with a plastic vapor barrier. I had alot of concern as to whether or not the floor would hold up, however it was such as small space I was ok with the small investment required. Five years later, I have zero regrets. I'll be refinishing it soon as part of the regular maintenance but it has worked out wonderfully.

Just my anecdotal experience. If i had 3in more headroom however, id have installed sleepers.
Peter

[Jeff Duncan]

A couple quick thoughts….

If your building the floor up your going to want 3/4" ply or wafer between the solid and the sleepers. The pine by itself will have some flexibility to it, so you want to support it. Also if your thinking of heavy machinery, i.e., machines over 1000 lbs, it may be worth further research to see if closer spacing of the sleepers may be required? If the concrete is fully cured I think I'd skip the sleepers altogether though. You can lay down some flooring paper and use a power set to shoot the 3/4" material right to the concrete. I've done this before and it's fairly straightforward work. As long as the concrete is, and will stay dry, the sleepers add no benefit and only create more work and expense.

As far as the wood itself goes that seems a bit high on moisture content. I'm thinking you may want it a bit drier before installing. At the least I'd let it acclimate to the shop for several weeks before installing.

good luck,
Jeffd

[James Conrad]

As an alternative to what has been mentioned, lay down rigid XPS insulation, tape the seams and lay down Advantech T&G ply over. If you can swing it, get 7/8" or thicker Advantech. No need for sleepers. The XPS should have a minimum of a 25psi rating, you could prob get away with 1" in your climate and it acts as your vapor retarder. As long as you have a fairly flat floor you shouldn't have screw it down either.

[Jim Andrew]

I did a floor with 2x and t&g flooring on 19 3/16 centers, takes 5 boards per 8', and is less than 16" between sleepers. If you have your shop layout done, you can put some extra pieces of lumber under your machines to make it solid. Don't nail your sleepers down, once they are covered, they will not warp, and the next owner of your shop will probably want a concrete floor.

[Dennis Nagle]

If you are thinking about doing this to fight fatique, you might want to look at locking rubber mat.

[george newbury]

If you are thinking about doing this to fight fatique, you might want to look at locking rubber mat.

How well does the locking mat work with sawdust and dirt being ground into the joints when you walk around?

I make a lot of sawdust.

[Joe Cowan]

I did my shop about two years ago and used the advice from one poster that had researched how gym floors were installed. I bought kiln dried pressure treated pine and cut them all 3' or less. After putting down the plastic, I put a row of these sleepers without any screws, then the 2" rigid insulation, another row of sleepers (again without any fasterners) and so on. I put the Advantech, and a red oak T&G floor. All is great after these two years.

[Dennis Nagle]

It works really well. They lock tight and if dust gets in the cracks, it just tightens them up more. Before I did that, I use to leave sawdust on the floor to stand on and my doc said that is the best thing to do. Standing on a completely even hard surface for hours is very hard on your feet. Standing on a soft irregular surface (sawdust) will keep the bones in your feet from having the same pressure points all day.....that is what makes them hurt. Better than soft mats....that is why I took them out.

How well does the locking mat work with sawdust and dirt being ground into the joints when you walk around?

I make a lot of sawdust.