Hi All:
I’ve moved to a new home and shop. A very wet area. Mendocino, Ca. My shop has a concrete floor with moisture coming through to surface. I would like to put down a plastic vapor barrier and then a plywood floor on sleepers made from 2s4s ripped in two. I need 35 sheets of plywood and am asking for advice on what to use that would be the most economical choice. Thanks in advance for your help.
Replies
With the price of sheet goods what it is these days, I've noticed some builders going back to rough sawn 1x8/1x10 lumber for wall and roof sheathing on houses. You could do the same for a floor over sleepers. If any moisture get's past the vapor barrier (which it probably will), the lumber would breathe better than plywood or OSB. Plus, it would give your shop such a nice atmosphere. Maybe you can find a local mill that would shiplap or T&G the wood for you at a reasonable cost.
You may want to comsider putting your sleepers on 8 or 12 inch centers. Moving equipment around on a wood floor that sags between joist can be challanging.
Garry
http://www.superwoodworks.com
Lots of things and options here. If you paln it right, and you have a DC you can set it up so that the area between the sleepers becomes a conduit for the DC. You can also possibly run wire for floor outlets thru some (not the same ones used for DC).
Will you be putting down any sort of sealant on the concrete before putting down the vapor barrier plastic.
Awhile back there was a discussion here (or in breaktime) on the newer sealants/coating for garage floors - might want to do a search and see what was said, it might help your situation. And I would definatly post a question over in breaktime. It does not sound right that you should have water coming up into you garage like that. I would be concerned about what is happening below and possible effects on the foundation1 - measure the board twice, 2 - cut it once, 3 - measure the space where it is supposed to go 4 - get a new board and go back to step 1
I'm designing my new shop (24x32) which will have framing above a poured foundation. I'm considering your suggesstion for sleepers deep enough for DC and electrical. Perhaps treated 2x6s on edge 12 inches on center to give enough depth for 4 inch pvc pipe. I also have all that depth for insulation - perhaps 1 inch rigid foam in the bays with pvc, and pink insulation in the other bays - though I am concerned about using pink stuff in the event it gets damp. I'm planning on putting 1 inch plywood down with screws so I can lift pieces to change the DC and electrical if I move or add machines - or if I need to beef up framing under a heavy machine or lumber rack.
2x8s would give you room for 6" d.c. pipe, which is more and more the recommended minimum size for small shops. Being able to move the pipe and electrical recepticles as machine layout changes would definitely be a concern with this system.
Thanks for the reply. Do you have any references for articles on 4" vs 6" DC pipe? Or pipe sizing in general for that matter. I have a Delta DC at the moment. Forget the model, but it's a 2-stage collector from the pre-cyclone days. It worked very well in my last shop, though the longest run was about 25'. Thanks.
Do you have any references for articles on 4" vs 6" DC pipe? Or pipe sizing in general for that matter
I thought doing DC "right" would be pretty simple. I learned better when I read a book on dust collection. If you really want to get precise, there's a LOT to it. Rockler (among others) sells a good book on the topic, "Dust Collection Basics" by Woodstock International. It's only $6 and 37 pages, but it introduces a wealth of information.
Honestly, I was so overwhelmed by what it would take to do it by the book, that I just took my Delta DC and added a chip separator (trash can with special lid), and a bunch of Y's, T's, blast gates and hoses. It seems to work.
If you're near Redmond you can borrow my book. :)My goal is for my work to outlast me. Expect my joinery to get simpler as time goes by.
This is the best source of info. on dust collection that I have found. It takes a little while to wade through, but you will be amazed at what you learn.
http://billpentz.com/woodworking/cyclone/Index.cfm
Thank you John D and Northboundtrain. I figure no matter what I'll start with my existing collector - a Delta 2-stage that has a metal collar inside the first 55 gal. drum that makes it sort of cyclone-ish. I've now decided not to go the under-floor route. I figure I'd rather have more ceiling height (9'4"), and I'll only need one drop in the middle of the shop. The floor will most likely be 2x4 sleepers with rigid foam and plywood. Then again, I have plenty of time to change my mind 4 more times before breaking ground.
Put down the plastic sheeting with seams taped. Then lay in tongue and groove plywood like Blandex. It is essentially waterproof!
Do not glue anything or use sleepers. All the equipment etc will keep the floor tight and flat. This is the way I did my floor and have had NO problems. None!
But make sure the plywood is the "waterproof" type used for floor underlayment. I used the brand Blandex but there are others.
By the way, I run a dehumidifier 24/7 in the shop.
I like that blandex idea. I didn't even know you can get tounge and groove plywood thats waterproof. This could be the solution to my problem.
Tell me is there any unevenness between the panels? If so would something like carpet tape help that? Also.. How much is this stuff and can I get it at HD or loews? Does it come in various thicknesses?
Thanks
There is minimum uneveness between the T&G joints. Not enough to worry about. The equipment keep all the panels flat --- at least in my shop.
I'm not sure you can get the panels at a box store but most any lumber yard will have them. I think they are all available in only one thickness -- about 3/4. And they are heavy!
There are several brand names out there such as Advantec or Blandex.
I put mine directly on a concrete slab with no sleepers or plastic underneath and have had NO problems. I do run a dehumidifier 24/7 but it stay mostly off so I must not be getting much moisture in the shop. I run the dehumidifier mostly as a preventative against rust on tools and so far have had no rust and I live on a lake front lot.
Just my experience.
A bad day woodworking is better than a good day working -- yes, I'm retired!
What you might really want to do is determine why there is moisture coming through the floor and solve that problem before attempting to cover it up with plywood on sleepers. I live in Northern Oregon where water tables are frequently high and there is a lot of surface water to deal with as well. Almost always, the problem of a wet floor or walls, (although more typically seen in basements) is that of incorrect grade and or drainage. In the long run, the "best" cure might be to examine and correct these issues first. Wood over moisture, no matter how well you tape, tarp, or try to seal from above is usually not a real great fix. Hope this is some food for thought for you, good luck!
sanderdude
I had the exact same problem with my old shop, which was located on a low spot on my property. When I built my new shop, besides choosing higher ground, I wrapped the back and sides with perforated drain tile, about 12" under the ground in trenches filled with gravel. They sell the kind with a mesh-like silt screening, and it works great at keeping the mud out. My property is very hilly, and my shop is cut into the hill so the back of the property is 33 inches higher than at the front of the shop. I had to deal with the water, and this has worked great!!
If you use sleepers, put them close together, and make sure you use treated lumber. To prevent squeaking and movement, epoxy them to the concrete floor, as well as drilling them in. When I bought my old house, half of the first floor was a slab on grade with sleepers, not done correctly. Noisy as hell! I'm in the process of ripping it all apart and using epoxy to stop the noise.
Jeff
just had some hardwood floors installed in my house....
glue down, slab..
my slab doesnt' have the moisture yours does, but the floor guys rolled on a two part epoxy sealer.. dont recall the brand, nor price, but it was blue...
not sure if your slab is too wet for this, but according to mr. floor man, it acts as a moisture barrier... they didn't put any plastic down on top of it..
might be worth looking into.. but im sure its more $$$ than plastic..
I wanted to put in a subfloor in my basement for two reasons: one for the insulation value and two for a barrier in the event of seepage. the guy at the big box store directed me to the pink 4' x 8' sheet insulation. I put down 1/2" thick foam insulation and 1/2" partical board with a layer of plastic in between. Only time will tell for the moisture but I can tell you that the floor is MUCH warmer than before.
Muleboy.
Sounds like your shop is about 1100 square feet. Good size.
Mine is 388 sq. ft. The floor was sealed concrete. Looking to upgrade, insulate and get more comfy, I went with 1" rough sawn pine. About $.45/board foot. I had to dry it and plane it, but it sure looks and feels nice. Given the price of sheet goods, you might be able to find a cheap source of native soft wood like I did. Allowing for waste and extras, my flooring cost about $220.
I glued and [powder actuated] nailed treated 2x4 sleepers every 12" or so, with 1 1/2" foam laid between, then a sheet of 6 mil plastic over it.
There was an article in FWW about flooring a couple of years ago or so.
I'd sure recommend you think about a pine floor, if the esthetics appeal to you.
Whether you are able to reduce the amount of moisture getting into your area or not, I higly recommend the dricore panels sold by home depot. I laid the panels in an 1100 sq. ft. (walk out) basement. It was the easiest floor I ever laid. Because it is a shop, I am intending to maintain it and keep the dricore panels as the finished floor for many years to come. However, you will pay significantly for this product. Cost per 2'x2' panel has gone up to $5.87 in my area.
merry christmas
Why dricore rather than sleepers/rigid foam/polyethylene/plywood? I was planning on the foam/plywood combo because it will insulate better than dricore, give a similar work surface, get everything further from any moisture that makes it through the slab, and cost not a whole lot more than dricore. Well, maybe almost twice as much.
Thanks.
i just had the same decision for my basement shop.
i went with a product called delta flooring. comes in sheets of 4x8 and rolls of 5'by 120 or so. works out to around $ 17.00 per 4x8 sheet. i went with that for ease of handling. it does two things. provide vapor and moisture barrier and provides even support for wood flooring. it is the same type of produt that the depot carries called dricore flooring, but delta is just the extruded plastic with out the plywood attacthed to it. it also is good if you get any water seep. it will not trap the water like the foam will.
i then covered that will 3/4 advantec plywood t&g which was costly. $ 50.00 a sheet. easy to roll the machines over and distrubute the load. did not nail anything down because its a floating floor. left 1/2 at the walls and ran a nice square base moulding.
now that i bit the bullet to say, shop is noticeably warmer, and a lot drier. in fact i shut my dehumidfier down and have no problem. i have to meausure the relative humidity just for my own knowledge.
lastly i painted the floor with good old latex and so far is holding up no problem, and a lot easeir to sweep up too! the best benefit is- it is a pleasure to work on, specially when going from concrete to wood.
let us know what you did!
What my be worth trying is cutting some redwood 2x6 in to 1 inch think blocks and epoxying it to the concrete. Try it in a small spot. Of course you might go nuts doing a whole shop. Would make a nice surface to stand on.
Good luck.
Troy
I have a basement workshop that frequently sees moisture. I also have a dehumidifier and rust free tools. The dehmidifier was cheap,cant say the same for the tools. Unless you have a Fort Knox moisture barrier I would get a dehumidifier and a bottle of scotch.
AB: I meant my dehumidifier reply for you and said Troy by mistake. I would like to thank all who replied with ideas for my shop floor. I have noticed that when it stops raining my floor seems to dry up within a day or two. I think I will put my $ into a french drain and dehumidifier first and see the results of that before spending to cover floor. Robert.
Hi Troy:
I am now considering a dehumidifier for my shop. Since moving in a couple of months ago it has started raining and now I see my tools and cast iron tabletops rusting. Found one rated for 1300 sq.ft. and down to 42 degrees f. I would like any feedback from those of you who use one in your shop. Thanks. Robert
Dricore - $1.5 SF for a complete floor that's easy to install and provides a channel for water which will always win isn't too bad IMHO. You can add other products on top like tile, laminates or just paint it.From everything I have heard, you should not be using any vapor barrier. Trapped moisture in dark places is the recipe for mold. If you can't stop the moisture as also mentioned, make sure it can flow to the drains it should have. Water always wins!
Here is what I did in some basement renos:
1. make sure moisture is comming from the floor and not through the wall, check your drainage if possible.
2.put down 1" styrofoam boards, the pink stuff, and leave a 1/4" expansion gap around.
3. tape all the seams with "tuck"tape
4. sprayfoam the expansion gap. This still leaves enough room for the styrofoam to expand and contract(sprayfoam is very flexible)
5. put down 3/4' TG plywood. Fasten it to the floor with tapcon concrete screws.
Believe me this works really well. I've used this method in europe 20 years ago and I know there is still no moisture in the subfloor yet.
Don't use a vapor barrier, all you need is a small hole were moistuire is coming in and you create over time a water puddle under your subfloor.
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