Between 705 & 1200 SQ/FT Andre’s Garage Build

[Andre3MC]

The time has come at last! I have wanted a garage my entire life and I can finally justify building one. We are just beginning, we are in the conceptual design phase. I have zero garage experience to draw from so I was hoping some folks here might weigh in to help pull things together.

Based on the lot setbacks we can fit a 24’x36’ (exterior) structure, and wouldn’t want to go much larger as we already have a small yard. The aesthetic concept is something like this :




We have three cars and do not plan to get more for the foreseeable future. The current lineup is a ‘21 Volvo XC60, ‘96 Volvo 855R, and a ‘15 VW Golf. I am hoping to have enough space to park all of the cars in the garage if needed and still have space for tools and equipment. I don’t plan to add a lift yet but would like to be able to in the future.

At this stage I am most interested in the design features that can’t readily be changed later. Things like garage door size, ceiling height, slab thickness, plumbing, electrical, and so on. There will be an accessory dwelling unit above the garage space so there may be some considerations there as well.

Really looking forward to hearing feedback. Let me know what you like about your garage and what you would change if you could.

 

[dmittz]

That is a beautiful looking rendering. I look forward to seeing you build it!

 

[rixtrix1]

Nice looking structure. I would recommend you go as high on sidewalls as possible, starting at 10'. The overhead storage space higher up with this wall height allows one to utilize more floor space efficiently. This, of course, is dependent on code and zoning restrictions in your area for total building height. If using conventional sectional doors, having high lift tracks will be beneficial to get the open doors up and out of the way of lighting.

 

[CombatNinja]

Doors on the 36' side are going to be a lot more conducive to parking 3 cars inside than o the 24' side. Even the shortest Volvo (the XC60) and the Golf will be a squeeze to stack into 36' with enough room to move around them. They'll a fit nicely in 24' with room in front for cabinets and workbenches. Just food for thought.

Edit: just did the math to sanity check myself. You'll lose 12" between front and rear for thickness of walls and setback for the overhead doors, so you'd be working with about 420" front to rear. Back out 24" from the rear bumper of the Volvo to the door (down to 396"), the Volvo is 185" (211" remaining), bake in 24" between cars (187"), the Golf is 168" (you're left with a 19" gap to the back wall). I don't consider that practical for planning on parking 2 cars front to back for the long term. Cars keep getting bigger and whatever replaces that Golf is bound to be longer. I really think if you want to park 3 inside, you should put the doors on the longer side.

 

[Andre3MC]

Things are coming together! I have building plans and have started pursing quotes on the build. I took a couple snips of the plans, let me know what you think! I want to beef up the concrete floor for lifts and other heavy commercial equipment, I am thinking 8" of 4000 PSI. I spoke to the power company and I will be able to run 3 phase to the garage which will be very nice.

The apartment must be under 800sqft per city rules, hence the extension in the front for the garage. In practice, we plan to use it as a two car with work space and don't want to eat up more of our small yard by extending past 36' deep for the garage. Because of the shape of our lot, the garage doors must go on the short side unfortunately. You can technically squeeze three or even four cars inside if you leave the space open but that wont be necessary for us on a regular basis. The golf is beater/grocery getter and can stay outside

I also put a bathroom/utility closet in a bump out under the rear deck which is going to make working in the garage more convenient. The apartment will have two mini splits and the garage will have one. We will insulate with spray foam so it should be pretty energy efficient.

Super excited to move onto the next steps, feedback is welcome! What features would you add in the design phase?

 

[dmittz]

That looks like a really nice plan. My only question is how high is the ceiling in the shop on the main level?

I have a coach house loft in my shop but in order to stay under my city's max roof height I could only get about 8'4 ceiling in the shop with an 8' loft above, so I did half full height (almost 18ft) and half with a loft above so that I could have enough height for a 2 post lift.

 

[Andre3MC]

The finished interior height of the lower level will be about 12' 2" which will fit most of the popular lifts out there.

 

[jcarapet]

I am always a fan of more is better, but what kind of commercial equipment do you plan on putting in to need an 8" slab throughout? More for a lift area always better, but throughout would add up.

 

[Andre3MC]

The thicker slab would be good for a car lift, which I want to be able to put anywhere when the time comes, and I would like to leave the door open for other lifting equipment. A 2T bridge crane/workstation crane would be very useful for the large pieces of steel I may need to move around. I work with superconducting magnets and the steel yokes can be quite heavy. That is also why 3 phase power is important.

 

[dmittz]

The finished interior height of the lower level will be about 12' 2" which will fit most of the popular lifts out there.

That is a prefect ceiling height for a lift and excellent since you will have a loft above as well.

 

[Andre3MC]

What are your thoughts on soundproofing? The walls will be spray foam insulated which will help but I am concerned about the garage ceiling. I am thinking two layers of rockwool safe and sound and two layers of 5/8" drywall but never tried it.

 

[dmittz]

What are your thoughts on soundproofing? The walls will be spray foam insulated which will help but I am concerned about the garage ceiling. I am thinking two layers of rockwool safe and sound and two layers of 5/8" drywall but never tried it.

This is something I have given a fair bit of though too in my garage build...

I've read quite a bit on sound proofing and its a trade off between effectiveness, cost and losing ceiling height. And there seems to be diminishing returns, meaning the better the wall/celing system is the less adding more 'sound proofing' does to improve it.

There are a few aspect,

1.) mass: heavy materials absorb sound particularly mid & high frequencies (drywall etc...)

2.) decoupling: decoupling the wall prevents a solid path for sound transmission, this is most helpful for elemininating low frequency sound

3.) sound dampening, materials that absorb and convert sound to thermal energy (green glue etc...)

4.) resonance dampaning, stopping sound echoing in voids (insulation/rockwool)

From personal experience it can get expensive quick and labor intensive when you start sound proofing. so you have to really consider how much you actually 'need' v.s what might be 'ideal sound proofing'. and also build the wall/ ceiling to deal with the type of sound you expect could be a problem.


So on my own build on the ceiling, I am opting to do 3 layers of rockwool safe and sound, then a layer of sono-pan followed by 2 layers of 5/8th Type X drywall. and then I have 1/4in of glue down cork being put underneath a glue down 6mm (1/4in) Glue down vinyl plank for the flooring upstairs. I expect it that will result in the ceiling having roughly a STC 53 rating, in otherwords it will reduce sounds made in the garage by about 53 decibles when you hear them in the loft.

If I had more head room and money and needed crazy good sound proofing I'd add resilent channel between the sono-pan and drywall, then green glue between the two layers of drywall or Mass loaded vinyl. But the extra thickness of such a system created issues with extending all my electrical light boxes and then I would have to upgrade all the common walls to also have a similar STC rating to be worthwhile. Additionally, resilliant channel can be a little tricky to install 'correctly' in regards to sound proofing as it can be easily 'sort circuited' by using too long of drywall screws or the ceiling electrial boxes (for lights), garage door track mounts etc...

Hope that helps!

 

[Andre3MC]

Great info! I cant find the Sonopan material near me but it looks like great stuff. I also do not want to chew into the garage ceiling height so I likely wont go further than 2 layers of 5/8 drywall on that side. Would green glue between the drywall sheets make a meaningful difference you think? I did not consider treatments to the apartment floor side of the assembly but I suppose that is another area to consider, cork under the LVP makes sense to me. How are you sealing your electrical boxes?