I'm planning my new house now and want a reasonable size shop (16'x25') for a
hobbyist. It will be used for making cabinetry, and furniture. I use water based
products for top coats so I am not planning on explosion proof fans etc...
My chief concern now is the floor. I was going to use a slab on grade with
overhead ductwork for the cyclone etc. My other half wants me to put it over a
crawl space with joists and a plywood floor just like the remainder of the
house. If I glue and screw the floor it should be pretty stiff and, that way,
the ductwork and electrical lines will be under the floor. This approach seems
expensive for a hobby. But more importantly, I am worried about the weight of
the table saw and the vibration from it and other equipment. I've thought about
bringing up a footing under the saw - assuming I will not move it after it is in
place. Is that adequate? What about electrical boxes in the floor. Won't they
just become sawdust collectors?
Any advise is really welcome. I really would hate to have to tear this thing up
after I get it done.
Not big enough ... make it at least 18' X 25' if you can. Bigger is better,
so stretch every foot out that you can, while you can ... you will be glad
you did. DAMHIKT
Pier and Beam construction will work fine, if done correctly. A wooden floor
is _much_ more pleasant to work on.
What about electrical boxes in the floor. Won't they
A few with spring loaded covers may be OK, but I shy away from too many
floor mounted electrical receptacles and duct work because you will
eventually want to move things around and they dictate what you can do more
so than wall or post mounted. A few won't hurt, however, and having a crawl
space to run wiring and ductwork is handy.
Just my .02 ... good luck on your shop.
Granted, there might be different rules for "shops" and industrial
buildings, but they are commonly used, and legal in most locales, in homes
... particularly in living rooms and dens for end table lamps, etc.
Probably safer than stretching an electrical cord across a pathway. :)
I agree! My shop is 20' x 30' with a little half bath in one corner
with an industrial sink in it. I was sure it would be big enough, but
it ain't. Although can ANY shop ever be too big?
I left my floor just the concrete slab. WRONG! You really need
something whether it be 99 cent per sq. foot hardwood flooring or the
cow or horse mats. I bought a cow mat, cut it in half and located the
pieces where I do a lot of standing and it helps immensely. It wouldn't
be a bad idea to cover the entire floor with them.
I had 9 boxes put into the floor and I love them! Sure they collect
sawdust, but the sawdust vacuums up easily, and they are SOOOO handy!
My dust collection system in another story. I keep my shop vac in the
center of the shop and just connect it up to whichever tool I happen to
be using. I also have a squirrel cage blower air filtration unit I
built which helps keep the fine dust down.
Someone made a good point about clogs in the pipes if you locate the
ducting in the concrete, but a channel grid sustem might solve that
problem pretty easily.
I don't think you mentioned anything about lighting. Put in LOTS of
ceiling light fixtures an different banks so you don't have to light the
whole shop if you are just using a small part of it. I have 30 fixtures
in my shop and there are STILL places where I need auxillary lighting.
Don't let anyone talk you out of any light fixtures.
I bought a building with slab on grade. The stability is nice, but
there are a few things I'd like to be different. It will take sawing
concrete, but I will (sooner or later) cut a channel and run 4" dc,
iron pipe for air and conduit for electricity to a point in the center
to serve the table saw and work bench. With a suspended floor this
would be a LOT easier.
Parking structures for cars can be built with joist/deck methods. Are
you working with an engineer? They can spec a floor that can carry
whatever machines you might want. Note that stiffness and load bearing
ability are not the same thing.
Electrical outlets in the floor do fill with sawdust. My plan at this
point is to make a single box in the floor with a flush cover should
the use of the building change. In it will be a single 220 receptacle
for the saw, a single 110 receptacle which will feed a row of outlets
tucked under the overhang of the bench and a dust extraction port.
Since I won't be plugging things into or out of the devices in the
floor often I can use tape of something to seal dust out of them.
All other machines are either located around the perimeter of the room
or are on mobile bases and get used in various locations.
Check the codes on floor mounts. It may be just as good to have a piece of
pipe protrude from the floor for about 12" and mount the receptical on that.
It still save a wire across the floor. Your electrician should know the
codes on that sort of thing.
And the advice to find someone who can spec out a floor is excellent.
Personally, I agree wood is nicer (though if cost becomes a _real_
issue, concrete is tolerable) and having the crawl space to run
wiring, etc. is good.
They make wood trusses as well as other means of carrying a load
suitable for your needs (which shouldn't be nearly what a garage would
require, but more than a standard residential floor).
If at all possible enlarge that space. I am building mine and its a 30 x 40
basement. It's a bit large but I wanted a place to work on cars as well as
woodworking. I used a 20x 20 garage and building a bookcase it took all the
space. I ended up moving the carcass outside several times to work on.
Typical framing should be more than adequate. But the simple thing to do is
ask you builder to cut the joist spans in half in your shop are. Or even
your could cut the joist spacing down from 16" to 12". Beefing up your floor
framing in the shop area would be simple and cheap when it is being built.
Probably no necessary but you won't regrett it. And it shouldn't add more
than a $250(?) to the cost of the house if that!
Put you outlets in the wall around 4'6" high or somewhere along that. There
easy to get to and ablove any benches you add. And be sure to include some
220V outlets too!
The man that allways tells the truth never has to remember what he said
Vibration? Not an issue. to transmit that vibration from the floor to the
rest of the house, it would have to vibrate the sill which is bolted to the
foundation. That should dampen most of it.
Support for heavy machinery in the center... that depends on the size of the
floor joists and the span. Don't overlook the possibility of steel beams. I
found the steel beam that I used under my second-floor shop to be both cost
effective (halving the span allowed for much smaller joists) and rock solid.
As for dust collecting outlets in the floor... I'm not a fan of
floor-mounted outlets, but what I did for my CS was to mount the outlet IN
the floor (not on the floor, but on the side of the floor joist) under a 4x5
cover with a hole just big enough for the cord. I just feel a little safer
with the business out of the way if an accidental kick or shuffling of
equipment made contact.
I have one DC run in the floor.... It's nice.
The crawl space option sounds like a significant step up in cost, but it
will provide a much more flexible and comfortable space.
I'm replying prior to reading any other replies to your post, but I'll bet
my advice to you is contrary to most of what you'll get. I'll find out
My new shop will be 24 x 40, with radiant floor tube heating. I thought
about putting in the crawl space/joist approach, with dust collection and
wiring underneath, and discarded the thought for a couple reasons.
One, if you have a problem or a clog, you gotta rip up the floor to fix it.
Not good. It's much easier to surface mount the wiring and dust collection
up high, plus, in my case, I can park a vehicle in the shop to work on it if
I absolutely have to. Can't do that really easily with a wood floor unless
you design for it beforehand.
Two, if you want wood floors, it's simple to lay down strapping and screw
some plywood or T&G pine down to the strapping. I plan on painting my
concrete floor with a good epoxy paint with some grit in it, and then
putting in some thick rubber mats, like used in horse stalls.
Electrical boxes in the floor would definitely become sawdust collectors,
even with good dust collection, and besides, you really want to bend down to
the floor every time you need to unplug something?
One idea - if you know where your tablesaw is going, or any other machine
that will have a known place in the shop and not be near a wall, you can run
a piece of PVC pipe with elbows under the floor slab, with a stub up out of
the floor at the saw and at the wall. Basically, a horizontal piece just
under the slab. That way, you don't have to run a drop from the dust pipe,
you can run the dust pipe right to the wall stub and hook the saw up to the
floor stub. If you know you'llbe moving the saw around, you can still do
the pipe thing, but cut the one in the center of the floor off flush, and
just use an adapter and a flex hose. It'll prevent you from tripping over a
floor hose, or letting a ceiling run get in your way.
You might think about laying down two layers of plywood running in opposite
directions. It would add extra rigidity and strength.
I'm not an electrician or expert on code so take this suggestion lightly. But I
often thought if I were to have a wooden floor I would run the conduit up
through the floor a short way and the box would be vertical off the conduit.
The reason is a round hole is much easier to plug then a rectangular box size
hole. And yes the boxes in the floor I've seen are dust, dirt and anything else
catchers. Another reason for being off the floor.
Listen to your other half, she's right. Wooden floor is comfortable
and warmer. If the floor is designed correctly , any machinery for the
home shop can be placed on it without any concerns. I used engineered
I joists over a twenty foot span, with a beam down the center. This
gives me 10' -0" between supports. Joists are 16" centers with 3/4"
OSB glued and nailed. I added 1/4" luan plywood on Osb after shop was
done. If I had used Advantec for the sheathing the under layment
plywood would not be neccessary.I did not know about Advantec until
after I had built the shop.
I have two boxes in the floor, one 220 volt for tablesaw and a duplex
120 volt for dust collector and joiner.
Forget about adding footings for machinery, make sure you have an
architect or engineer either do the drawings or go over what you draw
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