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Community and Q&A

Converting a Two-Car Garage Into a One-Car Garage

PLIERS | Posted in General Questions on

Hi, hope everyone is doing well. I will try to explain this quickly as possible. Basically I want to add an addition to my house. Right now I have 2 car detached garage in rear yard. I originally wanted to add a side garage with master suite above and remove old garage but the cost is way out of budget. It would be much cheaper to add a side addition master suite to my first floor and leave garage as is. I never use my garage for cars but want my garage for storage, workshop, etc. my backyard is small for my kids so I was thinking of converting my 2 car garage to a single car garage. It is also in a spot that is grandfathered in, if I take it down I can never build a structure there again (I would need to move over to follow building restrictions). It’s a gable roof, a beam runs down center of garage holding it up and separating the 2 bays. There are 2 separate doors already. Is it possible to build a wall right under my middle beam and then create a new smaller gable roof. Then just remove the right side of garage. Is this more trouble than it’s worth, will it be much cheaper to somehow just tear down and build in same spot if that’s even allowed? I want a garage even if addition blocks my ability to pull my car in because again I never do that especially with a midsize pickup it doesn’t fit.

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  1. charlie_sullivan | | #1

    It sounds possible, but I'm not sure what you'd do with the foundation. Is there a concrete slab now? You might need a footer under that new wall.

    You can get a pre-fab single-car garage or shed the size of a single-car garage, which might in the end be cheaper than the conversion.

    I'm not sure I fully undersand why not keep it the size it is and have more storage space even if you aren't parking in it.

  2. gusfhb | | #2

    Sometimes you will see a building with one wall standing and a whole new building being built.
    They then tear the old wall down and replace it
    happens when you have litigious neighbors or fussy city boards
    Someone waits until you tear the wall down then objects and you lose the old garage and new

  3. andy_ | | #3

    "How hard would it be to convert a 2 car garage into a 1 car garage?"
    Easy. Just leave one car outside.
    As far as removing half a structure, it's going to depend on what's holding it all up. The outside walls are typically on a substantial footing, while the slab is just a couple inches of concrete. That means that it's not as simple as just framing up a partition wall and knocking down the rest.
    It seems like a lot of effort and expense for a questionable end result.

  4. Expert Member
    Akos | | #4

    I did something close to what you are thinking about a while back.

    The garage with the red door is my neighbor's (the two are attached), mine was exactly the same before.

    It was in bad shape plus I wasn't using it, so I converted it into a storage shed, a car port and a pergola.

    I didn't want to touch the roof as there was no easy way to disconnect from the neighbor, I ended up support the whole thing on two giant LVLs that span the backyard with a big header between them where the outside wall was.

    I built up the LVL+header inside the existing walls, jacked up the whole LVL+roof to level (the garage had almost 9" drop at one corner) and installed the support columns and removed the existing walls.

    Used angled slats for the pergola section so they give more shade in the summer. Great place to hang out in the heat.

    Probably more work than building from scratch, but it was simpler in this case. I didn't want to take out the slab that was in very rough shape, so I put patio pavers over it inside the shed and pea gravel on the outside. Can't even tell plus it keeps the weeds at bay.

    1. PLIERS | | #9

      Would it be odd if a did the same but I only opened the right side wall. So basically from front view there would be 2 garage doors but the side would open to the yard. I would put a partition wall in the middle and close off 1 garage and keep it. So a covered patio basically and I have the option to keep the garage door closed for privacy or open it up.

  5. PLIERS | | #5

    Thanks for the replies. Looks like it would be easier to leave it. It’s a very old garage, probably built in 30’s it is sitting on concrete slab. I’m waiting to hear from architect if I’m allowed to build an addition and keep old garage. The town has some kind of rule on how much property you can build on. Sounds like a ridiculous rule to me, hopefully they just let me build it smaller worse case scenario.

    1. gusfhb | | #6

      Usually it is about pervious surfaces, not wanting solid concrete block after block.

      Bathrooms and kitchens are expensive, bedrooms and especially garages are cheap. A plain two story with a garage under is not that much more than that same thing without the garage.
      Same roof, taller walls if you get my drift.

      1. PLIERS | | #7

        So I’m adding a bath and bedroom. I got quotes 70-90k more for a two story with a garage underneath rather then everything on first floor. Not including altering the current 2nd floor to make an access point to addition. Does that make sense, you said it wasn’t must more to add a garage underneath. Is my price just way over or is that industry standard. I’m in the suburbs of nyc, an area where prices are much higher than everywhere else.

  6. 1869farmhouse | | #8

    I live in a historic district and our property has a very large barn, much larger than is allowed in the city any longer.

    I was told I could not rebuild the barn, but I could repair it. So I repaired every single board with a new one :). Often times city codes are overly simplistic, use that to your advantage.

  7. richmass62 | | #10

    It's actually not that much work to add a new footing. you just have someone use a concrete saw to cut a hole square out of it, then you dig down and pour a big piece of concrete about 30 x 30 x 12 inches, or whatever the architects specify, and then you let that cure and then replace the concrete you took out. The biggest issue is that if you do this major alteration I don't know if your city would allow it without a special permit, due to the fact that it is non conforming with the zoning. Cost of the new footing can be under $500 but the cost of going for the special permit can be over $1000.

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