What am I forgetting?

[mshedb]

I have been following this board for some time and am about ready to build a detached garage. 24 deep x 32 or 36 wide (not sure what will fit yet; meeting with architect next week). Brick front and sides, hardiplank rear, hip roof to match the house. 11.5' ceiling inside. Storage-style trusses. 5" of 3500 psi concrete floor over 5/8 foil backed insulation over 10mil vapor barrier over 4" crushed stone over compacted soil (thanks, John H.). At least one high lift door. If 32' wide, two 9x8 garage doors and an entry door on front side. If 36 wide, one 18x8 and one 9x8 door on front, entry door on side. 1-2 windows on each side. Back wall solid. 3' concrete apron.

2x6 construction throughout to permit max insulation in walls. will eventually sheetrock inside. Heat via electric heater hanging in one back corner. Minisplit a/c down the road.

What am I forgetting to think about?

Thanks.

 

[The Money Pit]

Dude, you need to come by and check out my garage. I've done just about everything and more to mine over the last 20 months. You will always kick yourself in the end after everything is complete. I, forutnately have had time to think things over DURING the long process of building mine. Where in VA are you?

Casey

 

[Down Under Bloke]

Just something you might want to consider if you are thinking of using Hardplank or any other James Hardie products.

http://www.actu.asn.au/public/campaigns/jameshardie.html

And this is the official company website, where you can find their point of view, http://www.jameshardie.com/

I offer no thought or comment on this matter, it’s a free world, you can form your own opinion.

 

[ZRX61]

Small shed/room tacked on the side/back for the compressor so you don't have to listen to it...

 

[thefairlaneman]

iF YOU PUT THE THING OUTSIDE SOMEONE MAY STEAL IT.

 

[ZRX61]

You're having a real problem doing the right thing about that stolen tool you bought aren't you? This is the 3rd thread you've posted something about it.....

 

[Special55]

If you're considering a lift down the road I would go with 12ft ceilings.

 

[mickeypat]

Two things, make sure that you wire the building so that you can turn off outside lights from the main house and that you install frost proof water faucets at every location that may be appropriate. You might consider hot and cold water faucets as well.

Is it really that much cheaper to use another material on the back, instead of brick? Good luck with your build up.

 

[boiler7904]

I have been following this board for some time and am about ready to build a detached garage. 24 deep x 32 or 36 wide (not sure what will fit yet; meeting with architect next week). Brick front and sides, hardiplank rear, hip roof to match the house. 11.5' ceiling inside. Storage-style trusses. 5" of 3500 psi concrete floor over 5/8 foil backed insulation over 10mil vapor barrier over 4" crushed stone over compacted soil (thanks, John H.). At least one high lift door. If 32' wide, two 9x8 garage doors and an entry door on front side. If 36 wide, one 18x8 and one 9x8 door on front, entry door on side. 1-2 windows on each side. Back wall solid. 3' concrete apron.

2x6 construction throughout to permit max insulation in walls. will eventually sheetrock inside. Heat via electric heater hanging in one back corner. Minisplit a/c down the road.

What am I forgetting to think about?

Thanks.

I'd use 2" rigid foam insulation instead of the 5/8" foil-backed. The foil backing isn't really going to do anything for you since there is a vapor barrier already.

Wire Reinforcement in the slab. Fibermesh may leave a little fuzz on the surface depending on how it is finished. You'll have to remove the fuzz if you add an epoxy floor finish.

Avoid sealing the concrete when it is poured if you're planning on using an epoxy floor system - it'll just have to come off before you put down the epoxy. It's time consuming and not a lot of fun.

Run an empty 2" conduit to the house. You never know if you'll want cable or a phone / dsl line in the garage later.

You said that the back wall will be blank. I'm assuming that you'll be hanging a lot of stuff on that wall. Add a lot of blocking / backing material in that wall now while it's completely open. As an example, if you know there will eventually be a row of wall cabinets, run a continuous row of 2x10 centered where you think the top of the cabinets will be. Another option is to cover the entire wall with 3/4" plywood before drywalling.

 

[RonBou]

I built mine 24 ft deep and wish it was at least 26 if not bigger. With 24 ft, if you put stuff on the back wall it is a squeeze to pull in a full size truck or SUV.....

 

[twostory]

For my concrete slab, I used 4,000# concrete. Did not really cost much extra, but the concrete finishers can get it smoother than 3,5000#. I would also use #4 rebar grid, on 12 to 16 inch centers. The rebar does cost some money, but nothing else will do as good a job as properly placed rebar (up on support chairs)
Your concrete may crack, but the rebar will stop the pieces from moving anywhere.

Also make sure the sill plate for your walls are not on the slab. I built using a stem wall, so I just made the stem wall 3.5 inches higher than the slab. If you are doing a monolithic slab, put a row of concrete block down, to build your walls on first. This way you can wash the garage floor, and not get the bottom of the walls wet when you do so. Also if I ever get a flood in my garage, it is no big deal, as my wall are 3.5 inches off the floor. Once the water is over 1/4 inch deep in my garage, it will run out the garage door.

 

[The Money Pit]

Remeber if you use 2X6's for wall studs, you won't be able to use R-19 because it's 6 1/4" thick. If you do use the R-19, if you ever hang drywall, the insulation will push the drywall out and pop screws/nails. You could use R-15, R-21 or blown in insulation. Their are some major issues you will have to tackle if you veer off from "standard" building practices. Also mini-splits are expensive and not as effeciant. They also take up valuable wall space and could be noisy.

 

[trovato]

Remeber if you use 2X6's for wall studs, you won't be able to use R-19 because it's 6 1/4" thick. If you do use the R-19, if you ever hang drywall, the insulation will push the drywall out and pop screws/nails. You could use R-15, R-21 or blown in insulation. Their are some major issues you will have to tackle if you veer off from "standard" building practices. Also mini-splits are expensive and not as effeciant. They also take up valuable wall space and could be noisy.

Here where I live (NY) 2x6 wall construction IS standard building practice to meet energy codes. And if compressing insulation that tiny bit pops your drywall, you must be doing something wrong.

 

[The Money Pit]

Here in VA everyone uses 2X4's. I'm trying to run things by him to help him out. Also it WILL push the rock out/down a little over time. How much time? I don't know. I DO know I have heard the rock popping like if you were walking on ice a few hours after it was hung due to the extra pressure from the insulation. It may be as simple as using screws instead of nails, but it's something to consider. Like I said, he could use R-21 rather than R-19 but it's a little more expensive.

 

[JohnZ]

I had the entire house and garage framed with 2x6, have R-26 insulation, and all the drywall was attached with screws - not a nail anywhere; not a pop or a bulge anywhere six years later.

My 42,000-BTU mini-split hardly takes up any wall space at all - it's 11' off the floor, 13" high, and only sticks out 9" from the wall.

You'll eventually want water, power, phone, alarm, cable, and some lighting controllable from the house out there (like the day after it's finished) - better accommodate those needs now - it'll be very expensive to do it later. You can't have too many electrical outlets, and don't forget extras in the ceiling for drop cord/work light reels; don't forget 220V for compressor, welder, etc.

 

[RonBou]

John, What brand is your mini split???

 

[The Money Pit]

Screws vs. nails. They nailed and glued mine and added some screws in the ceiling. The guys who hung it have been doing it for over 15 years so I've got faith in their work. Also as for my HVAC I used 2 seperate units. One for upstairs and another for down. The price for a mini-split would have been cheaper but more expensive to run. Also my upstairs is only 400 sq. ft. and the split would have taken up valuable wall space. Each case is different. Thinking things through entirely weighing pros and cons and asking these guys on the board are the best ways to get ideas and advise! Good luck with the build!

 

[mshedb]

If you're considering a lift down the road I would go with 12ft ceilings.

I shaved it down to 11.5' ceilings because height restrictions limit me to 15' from grade to the point halfway up the roof height. So, with 11.5 celings I get 7' in the attic for storage; 12 foot celings drag that down to only 6'.

I built mine 24 ft deep and wish it was at least 26 if not bigger.

If I can make 26' feet work on my lot, I will. Have settled on 32' wide.

For my concrete slab, I used 4,000# concrete. Did not really cost much extra, but the concrete finishers can get it smoother than 3,5000#. I would also use #4 rebar grid, on 12 to 16 inch centers. The rebar does cost some money, but nothing else will do as good a job as properly placed rebar (up on support chairs). Your concrete may crack, but the rebar will stop the pieces from moving anywhere.

Also make sure the sill plate for your walls are not on the slab.

I will explore 4000# Concrete. Have to consider rebar, but it strikes me as overkill - wire mesh for sure. The garage will have full footings with concrete block on top so sill plate will be at least 1/2 block off slab; since I am on a bit of a downhill slope, might be a full block off slab.

I'd use 2" rigid foam insulation instead of the 5/8" foil-backed. The foil backing isn't really going to do anything for you since there is a vapor barrier already.

Why 2"?

Run an empty 2" conduit to the house. You never know if you'll want cable or a phone / dsl line in the garage later..

Yes. At least one, maybe 2 of them. Also will have conduit up to the attic so I can pull wire after the sheetrock is up.

I will not be running water out to the new garage. It will not be that far away from the existing attached garage, and there is a slop sink in there.

Other thoughts?

 

[twostory]

I will explore 4000# Concrete. Have to consider rebar, but it strikes me as overkill - wire mesh for sure. The garage will have full footings with concrete block on top so sill plate will be at least 1/2 block off slab; since I am on a bit of a downhill slope, might be a full block off slab.

I recommend rebar placed on chair. This makes sure the steel ends up where you want it (1.5 to 2.0 inches above the ground, assuming a 4 inch thick slab). Getting the wire mesh to stay in the correct zone is very difficult. You have to step on it during the pour, which forces it to the ground, then pull it up as you move the concrete into it's final resting place. While the concrete professional can get it close, nobody can garantee it is properly place. With rebar, you step between the grid and never affect the rebar's position.

Also there are concrete saws that will cut "green concrete" (special blade). This allows one to cut the concrete immediately after the power trowel is finished. The sooner you cut the concrete relief lines, the better. If you wait till the next day to cut the lines, the concrete has already shrunk some, and the relief lines will not be as effective.

 

[ironroad 9c1]

Mshedb sent you a PM

 

[JohnZ]

John, What brand is your mini split???

Mitsubishi - here's the info:

http://www.villagephotos.com/pubbrowse.asp?folder_id=1411059