Help - Opinios on shop floor.

[Maurice Arney]

I need some opinions, either from experience or speculation. I am building a new shop (17X24) in my existing pole barn. Right now the barn has a dirt floor so I need to get a floor in for my shop. I am considering a cement slab vs a wood floor. The wood floor would be made from 2"x8"x8' pt joists 16" O.C. with a 4 1/2" X 8" (7 1/4") beam in the middle, all resting on 4' deep 8" concrete tubes (below frost). The finished floor sheathing would 3/4" T&G Advantech. The liumber for the floor would cost around $1,200 (and a favor owed to my healthy sons). I also got a quote for a cement slab, reinforced with extra re-bar for $2,500. The pros and cons of cost are obvious. A wood floor would involve a substantial amount of labor over several days, while a concrete floor would involve a lawn chair and some beers while I watch the concrete guys do the job. So what do folks think of a wood floor vs a concrete floor?

Thanks!

[Philip Berman]

Wood is more forgiving on dropped tools, footwear isn't as important with a wood floor because it's inherently a more comfortable surface to stand upon for long lengths of time, sweeping up dust and debris is usually easier than on a concrete floor depending on surface finish of the concrete, wood is more thermally neutral than concrete, and, to my eye, even the crappiest wood floor is nicer-looking than a sea of concrete. Whichever you do make sure you use some sort of vapor barrier to better control humidity.

Phil

[Tad Capar]

I would go with the wooden floor by all means. It'll be much better for you to stand on, much less fatigue on your legs and back. You can also incorporate prewiring and duct work in to wood floor much easier. The only time I would consider concreete, if it'd be a garage for cars at the same time or if you would want to put radiant heat in to it. You can also insulate woooden floor easier. You can sublet that work to others, if you preffer the lawn chair and beer instead. Have fun.

[Steve Milito]

I'd go wooden floor. I'd look at some span charts and guesstimate what kind of load you expect to make sure the spans and members won't flex too much.
I truly doubt the wood floor will be less expensive once you calculate the cost of putting in the reinforced concrete support piers, but I'd go wood anyway.

[Maurice Arney]

That's three for three on the wood! Steve, The concrete piers are actually pretty cheap if we make our own mix. I have a small cement mixer which will do enough for one pier in each batch. The tubes are only $3.56 each and the premixed concrete is about $3.50/bag. We only need 6 piers (3 down the middle and 3 down one side) because the shop will be in a corner. I suppose we could just sink some 6x6 pt timbers instead of the concrete which would make the job quicker.

[Phil Thien]

I'm voting concrete. But I'd probably put some insulation under the concrete to make it a little warmer. And I'd seal the top with something that makes it easier to broom. You don't have to paint it, there is stuff that will soak into the concrete and make it stain resistant and easier to sweep.

Concrete is hard (duh!) but millions of people work on it all day long. It just requires sensible shoes.

[Jamie Buxton]

I like the wood floor with a crawl space because it is easy to run wiring and dust collection ducting under it.

[Steve Milito]

That's three for three on the wood! Steve, The concrete piers are actually pretty cheap if we make our own mix. I have a small cement mixer which will do enough for one pier in each batch. The tubes are only $3.56 each and the premixed concrete is about $3.50/bag. We only need 6 piers (3 down the middle and 3 down one side) because the shop will be in a corner. I suppose we could just sink some 6x6 pt timbers instead of the concrete which would make the job quicker.

You certainly will save money by doing the labor yourself.
I'd still go through the exercise of going through some type of load engineering. A concrete slab will support anything you want and then some.
A 2x8 floor is more akin to a deck, and may not be the best choice if you have a number of really heavy machines.
Jus' sayin'

[Maurice Arney]

You certainly will save money by doing the labor yourself.
I'd still go through the exercise of going through some type of load engineering. A concrete slab will support anything you want and then some.
A 2x8 floor is more akin to a deck, and may not be the best choice if you have a number of really heavy machines.
Jus' sayin'

Ya I wasn't sure about the load rating. 2X6s are rated for about 9' so I just thought I would "up it" to 2x8s. It is only an 8' span so that seems like it would be enough. I could also put them on 12" centers. The last thing I want is a "bouncy" floor!

[Joe Hillmann]

I was originally going to say I would go with concrete, mostly due to the load it can carry. But then I went down stairs and checked what the floor joists in my building are. They are 2"x10" over ten foot spans and I have had vehicles parked on the floor before without any concern (although I have a 1inch oak subfloor and 3/4 maple floor to spread the load between joists).

How much does your heaviest machine weigh? If it is more then 1000lbs or so you could always add some extra support where you plan to put them.

Another concern about a wooden floor is, will rot be a problem being that close to the dirt?

[Steve Milito]

Ya I wasn't sure about the load rating. 2X6s are rated for about 9' so I just thought I would "up it" to 2x8s. It is only an 8' span so that seems like it would be enough. I could also put them on 12" centers. The last thing I want is a "bouncy" floor!

It depends on what you plan on putting on the floor. It's probably overkill for living space, but I don't think I'd want to drive a forklift on it.
I'm not a civil engineer, but I believe there are two things one looks at when designing a floor system. One is the deflection based on a live load, that what span tables specify. The other specifies the structure that hold the joists, that is the posts and girders.

I'm having a shop built now . When I explained my intended use to the architect, he recommended exceeding standard design criteria. I have a number of machines that weigh 800 to 1000 lbs. The planer sits on maybe 4 sq ft of floor at most. Granted you don't need to design a floor for 250 or 300 lbs / sq ft for a home shop, but clearly we both thought it should be beefier than the standard 40lb/ft. My floor is 2x12s on 16" OC, and it rests on triple 2 x 10s. The 2x10s are on piers 7' apart. The subfloor is 1 1/8" advantech.

I'm not saying 2x8 won't work, I'm just saying that you need to consider what you plan to put on it first, then decide how to build it (or over build it as in my case).

[Matt Meiser]

I would vote concrete. If you really want wood, lay wood over that on sleepers or use something like Dri-Core or DeltaFL and plywood. A wood floor would be quite limiting for future uses and could hurt resale. Concrete will be what a future buyer will expect to find. Or just use a lot of mats.

In my own pole barn, I had concrete in about 2/3 when I moved in. I lived with dirt in the rest (an unheated storage area) until 2 years ago. When I priced concrete I was pleasantly surprised at how much less expensive it was than I had assumed. The change makes working on the tractor and mower much nicer and because that part has a sliding door, the weather is much better sealed out now.

[Val Kosmider]

Concrete. Once and done with it. Put down soft mats to reduce leg strain where you stand for lengthy periods of time. Low maintenance, easy to clean, supports loads, smooth finish, and nice to have a hard surface underfoot for the occassional pounding/bending/support when you don't wish to worry about marring the finish.

Wood is beautiful, but that's about it in terms of functionality.

[Ole Anderson]

Concrete with a simple laminate over a premium vapor barrier/foam. Put the adhesive backed felt pads on all of your things that need to slide around, works great, looks great. If you are concerned about your feet, wear good shoes and put anti-fatigue mats at the locations you stand for long periods of time. Personally I think that issue is overrated.

[Maurice Arney]

Lots of great answers! Thanks everyone! At this point I am starting to "lean toward" concrete. It will be more expensive but the idea of having a crew come in and complete it in a day is enticing. And as a few have suggested, if decide I want wood or laminate later, I can lay it down over the slab. I'm going to give it some more thought for a few days. It will be a couple more weeks before the heavy trucks are allowed on my road anyway... Spring thaw you know.