Detached Shop or Extended Garage?

[Kirk Poore]

I am beginning to do a preliminary design for a new shop. OK, let’s be honest—I’m beginning the serious fantasizing phase before planning a new shop. The size will be roughly 500 sq feet, perhaps 25 x 20. The next basic choice is this:

Do I extend off the back of my garage, or have a detached building?

Basic assumptions: If I extend off the garage, I will keep the current garage wall so I can take the cars in and out without losing the heated or cooled shop air. In either case the shop and garage will have a large door or doors allowing a car to be parked in the shop. This is so that when I sell the house in a few decades it will appeal to both a home mechanic as well as a woodworker. And it will let me move in large machinery restoration projects. Both shops would have separate heating and cooling from the house.

Garage shop:
Advantages:
Save on wiring.
Can leave the rotary phase converter in the garage, and set up a dust collector and compressor in there too, thus keeping the noise out of the shop.

Disadvantages:
Will remove a good portion of my lawn
Air conditioner compressor will have to be moved
RPC/DC/compressor will be audible in the house, as will some machinery.
Limited roof options due to current garage configuration.

Detached shop:
Advantages:
Will occupy a seldom used playset area in the yard.
Noise will be less likely to be carried into the house.
More roof options, which might include a higher ceiling than the garage (currently almost 9')

Disadvantages:
Increased electrical cost to run external wiring
Some space taken by a RPC/DC/compressor closet
Increased cost from building the 4th wall.

What other factors should I be taking into consideration?

Thanks...

Kirk Poore
O'Fallon IL

[Blaine Harrison]

Kirk,

I have my shop in the back of my garage. It's about the same size as you described yours will be, so I think I can give you some perspectives.

My shop/garage is heated with our old house furnace. The garage is only partially insulated, so it's not efficient and the garage doors leak air quite readily. That said, even with the furnace off, the garage shop never went below about 25° last winter (I live north of Chicago) even when the outside temperature got down near zero. However, aside from the increased cost for heating, I like that configuration.

The reason I like the configuration is because, with no wall between the shop and the parking spaces, if I need some extra room to plane longer boards or need more room for assembly, I have it. The infeed table of my jointer is between the parked cars. The open configuration also gives me a perspective of having a larger shop so I don't get clostrophobic.

If I were to build a dedicated space for woodworking, it would need to be a lot larger than 500 sqft. There is just too much that you need to keep in your shop to house it in that small a space. Having some more space in the "car" part of the garage, I can spread out a bit more. I have added wood storage and some old kitchen cabinets to that part of the garage so I can store wood and some seldom-used tools away from the area I use more consistently.

That's my opinion. Take it or not as you see fit.

Blaine

[Rick Levine]

I had the same dilemma a few months ago and decided to build a separate structure. I live on a 12 acre lot in New Mexico and figured it would increase the value of my property should I need to sell in the future. The building could easily be converted to a guest house because I included water and electricity in the plans.

Another advantage to a separate structure is the sound. I won't disturb anyone in my house no matter how loud my equipment is and no matter what time I work.

[Brad Townsend]

I have about 600 sq. ft. in a separate building. One thing I did that would eliminate a couple of the negatives you had for that option is put a steep pitch on the roof and put in a full attic with a floor. It gives me a lot of storage and the noisy compressor and DC are up there. Instead of putting in a permanent stairs to get up there (and taking up a lot of valuable floorspace), I put in a 3x6' opening with a trap door in the ceiling and one of those pull down ladders. It's also designed so that the ladder assembly can be swung up and out of the way leaving the entire 3x6 opening clear. Mounted above the opening from the roof rafters is an electric hoist for getting heavy stuff up. Don't know if a separate building is your best option, but if you go that route, put in an attic you can use. You will be very glad you did.

[lou sansone]

if your budget can handle it, my vote is for a separate building
Lou

[Rob Bodenschatz]

If your budget can handle it, my vote is for a separate building like Lou's:

http://www.sawmillcreek.org/showthread.php?t=17821

[Rob Bodenschatz]

Brad, could you post a picture of the trap door/ladder setup you're referring to?

[Jim Becker]

I personally would opt for a separate structure for the reasons you list as advantages. While there is a little more initial cost, it provides more options for a number of things, including natural light. And as far as re-sale, I tend to think that the separate building would be more valuable...more versatile since a future owner could use it for things they would never want to do with an attached structure. (Animals, etc.)

[Kirk Poore]

I personally would opt for a separate structure for the reasons you list as advantages. While there is a little more initial cost, it provides more options for a number of things, including natural light. And as far as re-sale, I tend to think that the separate building would be more valuable...more versatile since a future owner could use it for things they would never want to do with an attached structure. (Animals, etc.)

Thanks for all the comments. I was leaning toward a separate building, but my father (who has built three of his own houses, so knows more than me about such things) suggested adding on. I'm intending to go with a high ceiling, so enclosing part for noisy stuff like the RPC, dust collector, and compressor is a good idea. I'm not sure about plumbing, but I may rough them in to allow for future options. As for size & style, I live in a subdivision with only a moderately sized lot, so a larger structure is out.

I do want something reminiscent of the upper floor of this:

This is the millwork & machinery building of the old Hall & Brown Woodworking Machine Co. factory on North Broadway in St Louis. I'm kind of the resident H&B geek over at OWWM.com, and own three H&B machines. My preference is for an arch-top tall half-glass double door in the center and a pair of arched windows on either side. The left side of the building would have a single door for regular access plus a couple more pairs of windows.

Kirk

[Joe Mioux]

Hi Kirk:

I would assume St Clair county is the same as Clinton Co. (Kirk lives about 30 miles from me) that property taxes are going to be less on an attached extension to your home rather than seperate building.

Additionally, you may have to pay for seperate utility services because of the detached building. Two electric services, two NG services, Sewer and water if applicable, etc.

Joe

[Brad Townsend]

Brad, could you post a picture of the trap door/ladder setup you're referring to?

Will do so, hopefully tomorrow.

Okay Rob, you asked for it. First, the whole building and showing what I mean by the pitch of the roof:


This shows the access door with the fold down ladder. Since it's a 9 ft. ceiling, I rigged up a system of ropes and a pulley to lower the door. When closed, it held by those two blocks of wood screwed into the ceiling that rotate. It's the old "barn door latch" approach. Real high tech.



This view is from above looking down. It shows the frame I built to support the fold down staircase. You will note the hinges on the floor at the top of the ladder.



The hinges allow me to swing the whole assembly up and out of the way like so:



Finally, here's the hoist I mentioned mounted over the hatchway. It's suspended from a 10' length of 3" galvanized pipe so it can be slid back and forth.

[Alan DuBoff]

Kirk,

I think you should do both, add-on to the garage plus build a seperate shop. You know as well as anyone that you need to add on 12' per year. Come on buddy, let's get with the plan!

[tod evans]

if your budget can handle it, my vote is for a separate building
Lou

i agree with lou.