Will this work for workshop flooring?

[Greg]

Hey all, I want your advice on something. I just got a 16x24 workshop built and I'm trying to decide what to do with the floor. The floor right now is 3/4 treated plywood. It is not T&G much to my dismay. I assumed it would be so I didn't ask but it is not. Anyway, I went to the borg the other day looking at flooring options. I wanted to use the VCT tiles but the guy there told me the shrinking and expansion would be too much for the VCT. One problem I definitely have to account for is moisture. Right now, I can see the ground through small spaces between the plywood. Here's what I was thinking and what I would like your thoughts on. I thought that I might put down some plastic as a moisture barrier then make my own floating floor by laying down 4'x8' 1/4" masonite or mdf which would be nice and smooth then hold that all together with the VCT tiles, maybe even tape the masonite together but not attaching it to the plywood flooring so it "floats". Is this a dumb idea?

My other possible option is to put down the moisture barrier then install a laminate floating floor. There is a local store that has

6mm oak laminate flooring on sale for $0.69 sq/ft. I've read in other posts that it can be slick with saw dust but what about putting some poly on it then throwing the non-slip sand additive that is used in garage floor paint to give it a little grip. It would certainly look really nice in my workshop!

Another option...if I caulk/seal the spaces between the plywood could I use the rustoleum 2 part epoxy garage floor paint? I still worry about moisture with this option.

I have a limited amount of $ left for my shop so I'm trying to do something that will work but not cost $1000 dollars. Any advice would be appreciated!

Thanks, Greg

[bridgerfafc]

lay down another layer of 3/4" ply, glued and nailed, joints staggered from the first. paint it.

[DonkeyHody]

I agree. No use to get fancy with a shop floor. First, you'll scratch it all up. Then you'll drill holes in it to get electricity to your stationary tools out in the middle. Then you'll cover it with sawdust, then you'll spill glue and paint on it. I've got enough things to worry about when I'm gluing without worrying about whether I mess up the floor.

DonkeyHody "The best things in life . . . aren't things."

[Mark & Juanita]

What I did when faced with a similar situation was to run a second set of plywood (I may have used OSB -- don't do that, it splinters really bad) perpendicular to the sub-floor. That pretty much covers the cracks that you are seeing. You could half-lap or do tongue and groove if you really want to totally seal the cracks (I didn't find that necessary when I did it).

[Puckdropper]

Greg wrote in news:1bc59a84-aeff-45a9-b47f- [e-mail]:

Most people go with concrete, but that's probably going to cost more than $1000. (It never hurts to call and ask for a "back of the envelope" quote, though.)

Avoid the laminate. It can get SLICK.

Wood's probably your best bet for an inexpensive non-slick floor. Sometimes you can get engineered hardwood on sale for $1.50 sq ft or less, and I think parque tile around here runs about $1 sq ft.

You could also get some T&G plywood, and use the existing plywood as a sub floor...

Puckdropper

[Lew Hodgett]

If you go with a plywood floor which makes a lot of sense, don't leave it raw.

Prime it with a good oil based primer followed by a couple of coats of "Porch & Deck" enamel.

Will increase the life and make clean-up easier.

Lew

[jd]

find a nice small local sawmill.See if they will mill you (or if they already have) some low-grade pine 2xN stock - get the cheapest you can.

Lay it on perpendicular to the joists, so that when (not if) it warpos, it will crown in the middle instead of the edges. If you're really motivated, rout a groove in all 4 sides and put in a shim (effectively making it T+G).

I did a 2000 SF shop this way, and ended up spending more on the spikes than the wood..... I think it ended up costing something less than $400 for the whole thing.

Gives you a nice solid floor that doesn't damage dropped tools and is nice to your knees and ankles. If you do the T+G trick (I did) its pretty much airtight. no finish needed, it will wear smooth pretty quick, and (based on some of the old barns I've worked on) should last longer than the rest of the building.....You can lay it green, but it will shrink a good bit (this is why I used the splines). The splines also help make sure that the edges don't get uneven. If a spot does lift a bit and become a trip hazard, a few minutes with a plane, chisel, or belt sander will knock it right back down.....

-James

[Pat Barber]

Depends on your location, but I would shop around for some 1x6 t&g southern yellow pine.

This flooring has been around a very long time and is VERY tough stuff.

You don't even have to finish it but I think I would give it a few coats of stain or paint depending on your preference.

How far off the ground is your floor joists ???

Greg wrote:

[Greg]

At the lowest point, the joists are about 7" off the ground. I'll check into either a plywood or wood flooring. I think my problem is that I basically wanted to treat what is essentially the subfloor as the floor. I didn't account for this extra cost.

Greg

[Chris Friesen]

It's fairly common for outbuildings to not have a separate floor...I'm building a 8x12 shed and it will have only a single layer of ply (T&G though) for the floor.

Do you actually need to do anything? How much of a problem would it be to have small cracks in your floor? Are you sealing up the room and using A/C and/or heater, or will it have natural air circulation anyways?

If the cracks are the only problem, what about cutting small strips of ply or 1x4 and getting someone to hold them up underneath the joints between the sheets while you screw through both sheets of ply into the bracing strip. Voila...no more gaps.

Chris

[Swingman]

"Greg" wrote

The current gaps in the subfloor, since T&G was not used, are actually a benefit to you as plywood, laid with tight butt joints, has a habit of buckling with the weather, causing anything else you put on it to do likewise.

The advice to use painted 3/4" plywood over the existing subfloor, overlapping the joints, is a good one for a shop building.

You can use rosin/felt paper for a vapor barrier between the two it if makes you feel better, but I would not consider it a necessity.

[dustinpockets]

Greg How is the workshop built? Do you have a vapor barrier between the ground and shed? If not I'd strongly suggest that you have a vapor barrier between the shop floor and ground. Sheds built close to the ground without a vapor barrier tend to have the joists rot, and acquire a strong earthy odor. Higher moisture levels in the shop won't help the rust situation either.

Good Luck

[dpb]

Swingman wrote: ...

Any vapor barrier between the two (that is on top of the existing subfloor) is the wrong place and will do more harm than good...

A vapor barrier (or at least retardant) of a plastic on the ground under the building is a minimum imo unless OP is in a _very_ dry climate.

[Swingman]

Cite please.

Acutally, here is the correct way to use a "moisture/vapor" barrier on a wooden subfloor on a crawl/above grade space:

A vapor barrier (or at least retardant) of a plastic on the ground under

Plastic moisture barrier in contact with the ground eventually degrade to the point of uselessnes. I routinely use a 3" thick, non reinforced, concrete, drained, "mud slab" on the house I build on crawlspaces.

Used in conjunction with proper drainage, and with proper crawlspace ventilation (a code requirement in most locations), it is, IME, the most long-lasting method of moisture/mildew control with regard to floors, subfloors and floor joists in a crawl/above grade space.

[Swingman]

"dpb" wrote

builders, interested in saving a buck, fool themselves into believing the xMil Poly/plastic products sold in the construction business as "moisture/vapor" barriers will last.

As the author states, an alkali soil will hasten degradation of this oft used product. What he doesn't say is this degradation is further accelerated with bacterial action in the warm, moist environment found under houses.

As a builder, and because of the subsidence in this area of the Gulf Coast, many municipalities are now mandating crawlspace foundations (the city of Bellaire, TX is almost all mandated crawlspace in most parts), I spent a good deal of time trying out various ways to deal with moisture issues in crawlspaces. The above is exactly why I quit using "2,4,6 mil poly" "moisture" barriers on soil under the houses I build on grade/crawlspaces and switched to a polyethylene underlay with concrete mud slabs, and good drainage and ventilation, to mitigate moisture problems.

[dpb]

Observation...

That's a vapor retarder as opposed to barrier -- and I'll grant you did say paper, not plastic.

[Swingman]

"dpb" wrote

LOL ... nice try. Go back and read the _caption_ above the picture. ;)

[dpb]

Whatever you say if you have to "win"...

But read the full text and you'll ken the meaning...note they point out over concrete additional retarder _or barrier_ (emphasis mine) may be desirable over the concrete. Same goes for the ground.

An _impermeable_ barrier there is likely to cause condensation on the cold side.

--

[Chris Friesen]

Vapour barrier/retarder are the same thing...it's not actually a barrier, so they're switching to the "retarder" terminology.

The purpose of the vapour barrier is to prevent condensation on the framing/insulation. Hence it is usually placed on the warm side of both, to prevent warm (and hence more moist) air from hitting the cooler structure.

In cold climates it goes on the interior, in hot climates it goes on the exterior. There is actually a narrow geographical band where no barrier is recommended.

There's decent information at:

[Greg]

The skids, joists and floor are all treated.

Another layer of plywood sounds like the way to go but I'm curious...why another layer of 3/4"? Why wouldn't 1/2" or even 1/4" do? 3/4" seems like overkill to me.

Thanks, Greg