I am building an addition on to the garage to serve as a workshop. The garage ceiling height is 8’6″. I would like a higher ceiling in the shop, but I can’t raise it without altering the roof.
My idea is to dig down a few extra feet. If the slab of the addition is 21″ below the slab of the garage, that would give me extra height and 3 steps down.
Any comments or suggestions about this idea?
Thanks,
Paul
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Replies
Just remember that a pool is just a concrete boat that is full of water. If you take out the water...
it will float.
Make sure your water table is below the footer and you have a good sump pump.
A La Carte Government funding... the real democracy.
You might have to have a step up before you go down for safety reasons because of potential gas vapors from cars in the garage. I think it might depend whether your building dept considers it garage or interior space.
Paul,
Use scissor trusses to gain some ceiling height, or use a structural ridge and eliminate ceiling joist.
KK
GotAll
I have an 8' ceiling. I know what you mean, by wanting a higher ceiling.
But I can think a more PITA situation than having 3 steps in the shop.
I think you would be money ahead to redo the roof line.
Rich
My shop is dug-in 32" below my garage (walk-out on the low side). I just ran 4 courses of block, and painted dryLock on the inside of them, after filling the cavities with vermiculite. Wood framing above. Ten years ago.
Only leak (weep) came from my drilling a hole in the slab for an anchor bolt. Earth is a great moderator - rarely have to heat/cool it.
I can post pix this AM if it would be helpful.
Forrest
Thanks. Would love to see pictures .
Paul
Okay - didn't even straighten up for you! Original ~1930 garage on the right; I had put a slab and entry ramp in years ago, then leveled the ramp and made the 4' bump-out on the ramp recently, when I moved the garage door to the back. The sloped roof to the left started as a lean-to shed on grade; I extended it and dug down.
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You can see our decorative Georgia clay splatter.
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Now to the inside - through the door, you can see the 4x6 pane window of the bumpout from the first picture
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Here you can see how the tables clear the 4 courses of block - their top edge is visible behind the vice over the compressor.
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Forrest
Edited 3/22/2009 5:15 pm ET by McDesign
Tray ceiling to get additional height plus slab at the same level - for all of the reasons mentioned plus having garage bays available for project overflow etc. Make the new ridge bearing and you don't need collar ties at the 'standard' height.
Jeff
A guy I know chopped one hole in the center of the roof, another in the gable end, and picked the roof up with a crane.
Slightly expensive for that one day the crane was there, but cheaper and way more convenient than digging it in, and having to climb stairs.
Of course, there are issues with extending the walls -- your BI won't want to see them fold at that seam.
One good way to deal with that is to tie the walls to the ceiling joists using a perimeter loft (which is really handy to have anyway) that has sheathed bulkheads every so often to resist racking.
I've had perimeter lofts in several shops, ranging from just an oversize shelf to a full 4'depth. 3'is about the max I'd recommend. More than that, and things get lost towards the back, and you have to step back from the chop saw to flip boards end-for end.
So get those coolers, tents, and lawn chairs out of your shop, and into that loft!
AitchKay
I've had low cieling in a shop and been anoyed with it.
One thing you could consider. You don't need the high cielings at the walls as much as you need them a few feet away from the walls.
If you talk to the truss people. They can make you a truss that goes up a few feet away from the wall.
The one thing I can think of that is nice about taller walls is increased storage against the walls.
I like to have open shelves against the walls so I can display everything I could possibly need for projects. I don't care if they get covered with dust.
I like to be able to see them so I can remeber where they are. If they are hidden I can't find them.
If you don't have shelves you can put wood sheeting up so nails and screws will hold.
I'm with the others who think that going down isn't a good idea.
Changing roof lines sounds much easier. As someone else mentioned, you can also gain interior room with scissor trusses or stick framing with a structural ridge.
It seems that everyone wants to make their garage into a shop. The trouble is, even large garages make poor shops; by the time you 'do this' and 'do that,' you'll have spent as much as it would have cost to make a new building .... and still have an inadequate footprint.
Add to that the insulation, lighting, and power issues .... plus all the other things you want a garage for .... and the challenge mounts.
Digging down is a bad idea - unless you already have a steep driveway. A shop really needs grade-level access.
If, for some reason, you can't build in your lot, then it's time to rent some commercial space.
He's not turning his garage into a shop - He's adding onto his garage.
My mistake! Let's hope he doesn't try to 'park' in the wrong half of the garage!
Some of us ( me for instance) can't swing a separate building. I'll be lucky to get a shop in the two car garage.
That's my next big project. I've never had a proper shop.
It's just not in the cards. You play with what you've been dealt.
Assuming this is a stick-framed garage and not a cinder-block one, you could just jack up the whole garage, and lay three courses of block under the walls. You'd need to add another section to your garage door, tho.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Forget lowering the slab. You don't need scissor trusses or a structural ridge either. Just frame the roof and walls the same height and raise the ceiling joists higher where it works structurally and you will have a higher ceiling. This way you can use a normal rafter and ridge. The ceiling being raised to a specific height is what will hold everything together and your walls won't bow. This type of framing is done every day so that you don't need a structural ridge.
Joe,Depends on the pitch if raising the joist 1/3 up would work. Wouldn't get much on 6/12 and below. Assuming about 24 feet width. Good idea on a steep pitch.I get glulams cheap so tend to use them alot.KK
"Just frame the roof and walls the same height and raise the ceiling joists higher where it works structurally and you will have a higher ceiling. This way you can use a normal rafter and ridge. "
= a 'tray' ceiling, if you frame the slope at either end (optional). Otherwise, what KK said - you don't gain much up to 1/3 and above that it's a structural ridge (LVL or GL) or he could do a 'cathedral' ceiling with some sort of ties (and all the issues that cathedral ceilings have).
Jeff
Why 21" ?
1'-6" will give you 10' ceiling. 10" work fine in my shop, even with lights and a run of duct . I have plenty of head room for handling sheet goods and finished pieces that are 8' tall.
You'd rather dig a hole than fix a roof?
Family.....They're always there when they need you.
Yeah, but the hole is a nice warm/cool "burrow"!
Forrest