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Having a new seperate shop built its 1200 sq ft , and a basic shell , I am reviewing the best options for flooring. I haven/t built a shop floor in 23 years.! My ideas so far , put in 2 by 4 sleepers on 24in centers over the concrete , insulate between the 2 bys with pink foam insulation, plastic vapor barrier over that , and HD has for $11 a black osb waterproof sheathing, to be put over the 2 by 4 /s. A local mo .sawmill has 6in by 8 ft, 210 pcs per bundle of 1 in mixed green hdwds for $200. for a finish floor. Thank you .and what have you used, and what would you do differently ?? The shop will be located in guthrie OK about 1 hr N of OKC

If you have a concrete floor you want to build a sub-floor over it? For larger tools such as table saws, it's easier to move them on concrete than wood floors.

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Julie Moriarty
http://JulimorCreations.com

FWIW The only thing that comes to my mind is around stationary tools. Will the floor be stiff enough to keep them level/stable. If you don't use any stationary tools then disregard. I have several tools that are over 300 pounds and a couple over 500. My CNC machine is really heavy and needs to sit on concrete...

Best, M

My shop is similar in size (1260 sq ft). Leave the concrete and put those interlocking cushioned squares around your benches. It's amazing how much easier it is on your body to stand on soft pads instead of concrete or wood and its way less expensive than what you're considering.

I would put the plastic down first to protect the sleepers from moisture.

We built a shop at one of the tall ships I work on 2 winters ago. We wanted to use 2 X material for the floor so we could screw jigs to it as needed. We had a deadline to dedicate the building so the architect told us to lay the 2 X 6 boards on the sleepers despite our telling him that the gaps would open up. Well they opened up, almost all of it in the first month with the heat on. We should have let them cure for a month (or had them delivered a month earlier).

Also, OSB might not be strong enough if you have any cast iron stationary tools with feet - the feet could slowly distort the OSB.

Sounds like a big shop - mine is 640 ft2 and I consider myself lucky.

Ed

"I would put the plastic down first to protect the sleepers from moisture. "
+1
"A local mo .sawmill has 6in by 8 ft, 210 pcs per bundle of 1 in mixed green hdwds"

-1 "green" hardwood flooring will probably warp and shrink and create gaps that dirt will fill up. But I could be wrong.

I would space the 2X4 at 16 in O.C.. It wont cost much more and will be much stronger (strong enough to hold most stationary tools) I would use 3/4 inch CDX plywood for the finished floor (bondo any missing footballs) and use the 2'X2' rubber mats at any standing stations (or cover the whole floor).

Wood floors are so much easier on the legs than concrete, and with rubber mats even better.

John can you elaborate on the interlocking cushioned squares , where to buy from ?? I have 12 major power tools and they weigh a lot , Hmmm might just let them sit on concrete as I do here in my garage . I do have quite a few rubber mats, Any other ideas ??? thanks for all the tips and things to think about ??

The concrete will let a lot of moisture in so it's not a bad idea to subfloor it. But of course you can control that with dehumidification too. The wood floors would be easier on the body too. If you can afford it spray foam is incredibly wonderful stuff.

Here's a place that sells them:

https://www.greatmats.com/interlocking- ... 0dd4c66793


We bought ours at Costco but I don't know if they still sell them. They've been in place in our shop for 12 years and show no signs of wear. I'd guess them to be about 3/4" thick. My wife and I both noticed that the cushioning seemed to make us much more comfortable when standing in one place for hours. BTW, we had some extras and they make great kneeling pads for gardening or maintaining tools.

Depending on the size of one's workshop, how you lay out cushioned mats depends on the need to move tools around. In my last workshop I had to move tools around a lot. I had two mats, one at the workbench and one at the lathe.





I could slide them across the floor or pick them up to get them completely out of the way. Every large tool was on wheels so the mats needed to be easily moved.

As for dust, the concrete was sealed right after the basement floor was poured. In the 27 years since I built the house, I never sealed the basement floor again and never had a problem with concrete dust. Today there are epoxy finishes that are hard as rock so they would be good for a workshop floor.

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Julie Moriarty
http://JulimorCreations.com

The interlocking mats I have are 1/2 inch thick, 2 ft X 2 ft.. I bought them several years ago and they are still holding up fine. I haven't seen any 3/4 inch thick mats. Harbor Freight has some for about 50 cents a square ft. (1/2 in. thick by 25" square) but it seems like you can find them almost anywhere.

I would go through a lot to get a wood floor in my shop. We may be moving soon, and I’m hoping I can put one in my next shop.

I did a floor that I wanted rock solid a few years ago. I used treated 2x4 sleepers on 16" centers then glued and screwed 1/2" plywood on top of those and then glued and screwed another layer of 1/2" plywood on top with the joints in the plywood offset by 24". 300 or 400 lbs would not be an issue on that. Vent the area under the floor - just drill holes in the sleepers so air can circulate and put some vents in the wall, one on each end will do.

Having said all that I left my shop floor concrete and put down some cheap pads I got on sale at Woodcraft. Very comfortable to work on.

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Steve Smith
"Music is what feelings sound like"

I could be wrong on the thickness of ours, I was just guessing so they may be 1/2". At Costco they came in bundles of ten and were really cheap but I don't remember the price. We bought several bundles and it was not a big expense.

When are you expected to be up and running? I'm just east of you in Perkins.

Harbor freight sells interlocking padded mats for 8.99 for about a 4x4ft sq space. I have a few sets of these around my shop and have been really happy with them. I did get some velcro rolls and put some small squares of it under the mats to keep them from slipping

FWIW, I would avoid green wood flooring. You’re looking at a year to dry and shrink. It will throw off unwanted humidity into the shop as well. An epoxy concrete finish would work fine and be cheaper than a complex subfloor. Surface prep is critical if you want the stuff to last though. You can also stain the concrete cheaply before pouring the epoxy. Looks nice. I think I still have a gallon of the stuff from when I stained my shop floor. Let me know if you go that way. I doubt I will ever use it. Also, plus one on the locking mats if you stick with concrete. Much better on the feet, and also helps us clumsy types with random dropped items.


Sent from my iPhone using Tapatalk Pro

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Aaron Craig

Here’s a different thought. You’re in the middle of farm and ranch country (I think). What I found are stall liner pads. About 4’x6’ 5/8” or 3/4” thick solid rubber (mostly recycled tires). They give the padding you need but will stand having heavy tools rolled across. Up here, they cost $60-70 US.

Pretty sure you want to have any vapour barrier on the warm/air conditioned side of any insulation. If you put it under the wood sleepers and insulation, the vapour will condense, soak the sleepers, and cause mould growth. Treat the floor the same as you would an exterior insulated wall.
I agree that green wood flooring will cause nothing but head aches. Painted Aspenite, 3/4" on 12"-16" centres should hold stationary machines if you put a piece of ply under the machine's footprint.
Have fun in the new shop, Ernie!

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

The moisture movement in the basement is up through the concrete. 1000 ft2 of visually dry concrete can allow up to 18 gallons of water through it in a day. My company (mid-Atlantic) does this sort of thing - and when we do this in basements and crawlspaces, the condensation is alway on the bottom of the plastic whether the plastic is against gravel, dirt, or concrete. I have seen moisture on the bottom of plastic on an at-grade garage floor with sleepers many times.

For walls against concrete, we hang 6 mil plastic from the plate at the top, down the wall, and out the floor. We then build a stud wall with a 2X4 plate at the top, a pressure treated 2X4 plate at the bottom, and 2X3's for studs to save cost as there is no needed structure. The top and bottom plate is pushed against the wall, the plastic is trimmed off at the inner face of the bottom plate, and fiberglass batting is pushed back to contact the plastic on the wall (no contact, no insulation). Another way is to hang 2" thick styrofoam on the wall with taped joints, then a 2X3 wall inside that. With walls, the condensation always occurs on the outside.

Good luck

Does this still apply to Ernie’s shop, as it is a stand alone building at ground level?
I am by no means questioning your knowledge, Ed. I’m going by what is commonly done in your good neighbours to the north, with our 3’-4’ frost lines!

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

I'm just south of you in Norman.

I've got a feeling I'll be spending quite a bit of time down there over the next few years. My older son just graduated and is headed down to that other school

I am with Rick on this one. I covered my entire floor with these and could not think of a better solution. The rubber has saved a few dropped items as well as being easy on your feet.
Heavy and not easy to cut but well worth the effort IMHO.
I bought factory seconds for $20 each!

T

This what I used. Lay down these 2 x2 x 3/4" tongue and groove MDF squares with vapor barrier attached. I finished with a floor poly. Of course you need a nice finished concrete floor.
https://www.homedepot.com/p/DRICORE-Subfloor-Membrane-Panel-7-8-in-x-2-ft-x-2-ft-Oriented-Strand-Board-CDGNUS750024024/202268752

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