Between 485 & 705 SQ/FT 30x24 Modern Style Detached Garage Build

[bmwguy]

Long time browser of the forum, have enjoyed the great advice and conversation.

Thought I would share my relatively simple detached 2 car + workbench bump-out build that I have been planning for a few years. We have a 1970s mid century home in Chicago suburbs and it was important to have the garage match the house design exactly as it will sit in front of the house. Had a great local architect help develop the hand drawn design.

Goal of the project is additional storage, work / tool space, ability to keep longer term car projects organized without being in the way of the family vehicles. I did a 6 speed manual conversion on my M3 a few years ago and that type of thing will take over the current attached 2 car garage space fairly quickly.

I wanted to do a higher ceiling in the new garage but as you can see the pitch required to match the existing house would have made the back too tall. Going with a 9' ceiling and will just do a shorter vehicle lift at some point in the future. Leveraging "attic" trusses to allow for storage space in the higher area in the back.



Site plan below - new garage is on left, existing attached garage is on right, connected with a cedar trellis as required by HOA regulations


Will share as things progress. Currently waiting for final permit approval and planning to dig around May timeframe. Some feature level components I am considering for discussion if anyone has any advice:

- High lift garage door tracks with wall mount openers
- Looked at racedeck etc. but thinking i will do a professional epoxy floor
- May install a separate meter with 100A service, just for capacity for future electric vehicle charging etc. Would be easier than pulling power from house, otherwise would need to upgrade to 320 (400A service) as I dont have the capacity at my existing 200A panel.
- Would really like to do center floor drains to daylight out back but dont know that is going to pass code.
- Spray foam vs batt insulation? Thinking batt would be easier DIY and spray foam ROI not there for garage?
- Looking for LED lighting ideas to cover everything in a "normal" and "detail" mode.
- Likely doing traditional natural gas unit heater in the corner. Looked into mini splits, may be an eventual add-on but for mostly cooling.
- Exhaust fan / vent - looking for advice. general cooling and ventilation / light fume removal. There are decent looking Amazon deals for $200 or less.
- Hardie vs cedar siding - house is cedar and it has to be a really close match but already dealing with annual maintenance on my house cedar.

 

[rmckee]

Love the design @bmwguy! Those garage doors look like one of the style options we had with our CHI Overhead Doors. I went with the top row window options but loved the look of the side windows.

Some comments on your component discussions:

• We went with high-lift tracks and wall mount openers. I also got the rails and door hardware powder coated for $200 more per door to make the aesthetic nicer. I didn't want 50+ feet of aluminum rails with my plans to nicely finish the inside, so that was an easy upgrade option. Not ever garage door company does it, but CHI did.
• We also did a separate meter. Our electric company is running a new 200A service for $160. The cost to upgrade the house to 400A was going to be $5-6k so the breakeven time of a monthly service charge is a decade+ breakeven. I also never have to worry about screwing up both buildings by a mistake at one.
• Check out my lighting plan. I'm doing rows of 8' LED fixtures at 5000K in two zones for variable intensity, but complementing them with recessed 3000K lights for a softer look when the time is right. I joke that the recessed will be "beer drinking" light versus shop work lights with the 8 footers.
• We're doing open cell spray foam in ours. $3k difference over all batts. This is a 30 year house for us and I once read that "you pay for insulation once, you pay the HVAC bill every time the thermostat turns on"... I'd rather put the best stuff in now and reap the returns for years to come. My plan is a 2-zone 36k BTU mini-split, likely a Mr. Cool.
• Our project is going to be Hardieplank to match the house. Only maintenance is pressure washing.

Looking forward to seeing this project progress! Be sure to post up some photos of the M3 as well! Nobody here ever complains about too many photos.

 

[grant00]

Another siding option is LP Smartside Cedar texture siding. Maybe a bit easier and maybe cheaper than Hardie. Something to consider!

Floor drains for parking here can ONLY go to daylight. They are not allowed to be put into the sanitary sewer. I would bet you would be fine doing the same. I called my planning office and they gave me that information for my area.

I really like the design as well!

 

[bmwguy]

Another siding option is LP Smartside Cedar texture siding. Maybe a bit easier and maybe cheaper than Hardie. Something to consider!

Floor drains for parking here can ONLY go to daylight. They are not allowed to be put into the sanitary sewer. I would bet you would be fine doing the same. I called my planning office and they gave me that information for my area.

I really like the design as well!

Thanks for the advice. I will look into Smartside when the time comes.

 

[bmwguy]

Love the design @bmwguy! Those garage doors look like one of the style options we had with our CHI Overhead Doors. I went with the top row window options but loved the look of the side windows.

Some comments on your component discussions:

• We went with high-lift tracks and wall mount openers. I also got the rails and door hardware powder coated for $200 more per door to make the aesthetic nicer. I didn't want 50+ feet of aluminum rails with my plans to nicely finish the inside, so that was an easy upgrade option. Not ever garage door company does it, but CHI did.
• We also did a separate meter. Our electric company is running a new 200A service for $160. The cost to upgrade the house to 400A was going to be $5-6k so the breakeven time of a monthly service charge is a decade+ breakeven. I also never have to worry about screwing up both buildings by a mistake at one.
• Check out my lighting plan. I'm doing rows of 8' LED fixtures at 5000K in two zones for variable intensity, but complementing them with recessed 3000K lights for a softer look when the time is right. I joke that the recessed will be "beer drinking" light versus shop work lights with the 8 footers.
• We're doing open cell spray foam in ours. $3k difference over all batts. This is a 30 year house for us and I once read that "you pay for insulation once, you pay the HVAC bill every time the thermostat turns on"... I'd rather put the best stuff in now and reap the returns for years to come. My plan is a 2-zone 36k BTU mini-split, likely a Mr. Cool.
• Our project is going to be Hardieplank to match the house. Only maintenance is pressure washing.

Looking forward to seeing this project progress! Be sure to post up some photos of the M3 as well! Nobody here ever complains about too many photos.

Thank you, very helpful comments. Really like your project and detail, will dig in this weekend.

 

[jbrentd]

Welcome to GJ. I like the design and look forward to seeing future updates. Are you dead set on have 2 small doors? If not, I would consider 1 door. I don't think it would change to the looks much and (IMO) would be more convenient. It might match the existing structure better too, but not sure.

 

[bmwguy]

Thanks. I was back and forth with my architect on double vs single door. We ultimately decided that two doors looked better, adding character to the standalone building and would not let as much heat out when the door opens in winter - probably not a huge issue though. On the other hand, the middle beam can be a pain depending on what you are working on and multiple doors will add to the cost. I will likely make the final decision during framing, although the two door plan is under approval with the county right now (they seem very sensitive to changes). Will keep you posted.

 

[bmwguy]

Thanks. I was back and forth with my architect on double vs single door. We ultimately decided that two doors looked better, adding character to the standalone building and would not let as much heat out when the door opens in winter - probably not a huge issue though. On the other hand, the middle beam can be a pain depending on what you are working on and multiple doors will add to the cost. I will likely make the final decision during framing, although the two door plan is under approval with the county right now (they seem very sensitive to changes). Will keep you posted.

@rmckee - interested if you have any thoughts on double vs single door? I do like how the double doors look on your garage.

 

[rmckee]

@rmckee - interested if you have any thoughts on double vs single door? I do like how the double doors look on your garage.

I personally don't love the aesthetic or function of a single wide door on a building that is too much wider, and with a building that was 24' wide and plans for a lift I leaned more to the camp of having a very clearly defined pathway onto the lift through a single door versus a 16 or even 18' single. Our main house has a 16x8, and we went 9x9 on the detached so that it's still wide enough (barely) to get my 8.5 foot wide OBS Ford through. To me the 2x doors give it more character as a carriage house type vibe in our neighborhood.

As you mentioned I also wondered if there was any benefit for climate control to only open one door at a time. Whether or not that's true is another story, but at least it looks good!

 

[Chrisb62]

I prefer double doors also on a slender building but also a large door on a wide building if that make sense,,,,,

 

[PugetDude]

Along for the ride.

 

[bmwguy]

Its been a while since I posted - thought I would provide a project update.

Sold the BMW M3 to fund some of the build. Went to a great enthusiast home. Here is a photo loading onto the trailer. I had a lot of work into the car so was bittersweet but glad it went to someone that will enjoy it.


Been clearing the site and also removing invasive buckthorn in the woods.

Tree guys came last weekend and did a great job taking down 8 trees. Biggest one was a large oak. Sad to see it go but i will use it for firewood in my wood stove to heat the house. They took the trunk as no way I could have split it. Trying to do some overall better forest management and get more native plants growing in the front woods. Here are the results of the site clearing and the wood I am going to split.


This is the view looking up the driveway, the garage will be on the left, set slightly forward in front of the main house.


Also found out that the gas line goes right through my site (you may be able to see the flags in the photos above). No choice but to pay $1800 to the gas company to move. Good news is they are coming out on May 24th to do the work

In terms of supplies, I want to get ahead of any issues so I purchased 5 Anderson casement windows and my service door at home depot. Have these in storage for when I need them

I also ordered 2 overhead Clopay aluminum insulated garage doors from home depot. I was back and forth on getting designer doors, but just purchased the same insulated doors I have on the main garage. That way it matches and I can do an upgrade of all of them together if I want to at some point.

For the siding, I am awaiting a quote on LP board and batten. I think that is the option I need to go with vs. T&G cedar matching house - that is pretty much a non-starter in 2022. Would be interested in any thoughts on the LP product and also recent pricing ballparks.

If the gas relocation work goes as planned, hoping for dig and foundation in June.

Also ordered the trusses, they are expected to be delivered around June 20th. Ive given my framer a heads up and expect to put the actual structure up early July.

More exciting actual build updates to come, I just thought I would share some progress.

 

[jbrentd]

Nice place you have there. Seeing pictures of the site really helps me visualize the project. I hate to see you sell the BMW, but there will be opportunities for another down the road. It sounds like you're filling the role of general contractor. I wish I were able to do that on my build. I just didn't have the contacts for subs and the quotes I did get were outrageous.

 

[bmwguy]

Thanks.

Yes, I am doing the GC role. I like to think I am saving money but you never know. I figure it gives me more control on who is doing what and allows me to pick up the jobs I want to do without a hassle. I plan on doing all the electrical, insulation, unit heater install etc. myself.

After a bit of looking around I found a good local excavation / foundation guy (which is a big deal up here as I need to go 4 feet down with the footings) and the the lumber company supplying the trusses referred a framer that seems reasonable and easy to work with so far.

 

[jbrentd]

Thanks.

Yes, I am doing the GC role. I like to think I am saving money but you never know. I figure it gives me more control on who is doing what and allows me to pick up the jobs I want to do without a hassle. I plan on doing all the electrical, insulation, unit heater install etc. myself.

After a bit of looking around I found a good local excavation / foundation guy (which is a big deal up here as I need to go 4 feet down with the footings) and the the lumber company supplying the trusses referred a framer that seems reasonable and easy to work with so far.

On the lumber, are you able to beat the "any joe off the street" price by using the framer and his status with the lumber yard? Is so, that would be a big deal.

 

[bmwguy]

Hopefully. He will need to place the order as I dont have the materials list - that needs to be created from the plans. My understanding is he will place the order and I will pay 84 lumber directly which should be ideal. I got what I assume is the walk in price for trusses (16 "attic" trusses were $8000).

 

[Trapps]

Buckthorn *****. I feel your pain!
I used LP SmartSide boards on a shed and I'm happy with it (battens pending installation).
Any chance to consider adding a few windows, high up on the back side? Natural light is a big benefit, especially in the winter when the doors are closed.

Following along!

 

[bmwguy]

Good advice and thoughts - the ceiling will be finished in garage and the upper area is an attic. Still may make sense to get light in there.

 

[captain14]

Subbed.

 

[isonic]

Looks like a cool project. What part of the country are you in?

 

[bmwguy]

chicago suburbs

 

[bmwguy]

Back after 2 months -

Wet weather caused delays with the excavation and cement work, ultimately I had to find a new guy because the original one ghosted me.

Good news is we are well on track now, today the frames were removed from the foundation walls that were poured yesterday. Really looks big standing next to it right now on the lower side of the lot - grade changes feel so much more significant when you start building on them. Im sure it will even out once the grading / backfill / slab is done.

I am sharing a number of photos to show the progress to date. If all goes well the slab will be poured by July 15th and we will start framing the week of the 18th.

Initial excavation and footer framing


Footer pour - you can see some complexity there with the stepped arrangement due to sloped site




foundation wall framing

Foundation wall pour



bare foundation walls



pretty good sized diagonal shrinkage crack, although I assume it is "normal"



interesting how the chunk is torn off under garage door but i dont think this matters as it will be filled in with gravel and only supporting the slab



Interested in the everyone's thoughts

 

[Riley]

First off, great project!

Are the lines on the foundation actual cracks? Perhaps a remnant of switching trucks during the pour? The failure at the door looks a bit remarkable to me. I'd guess they could remedy it during the slab pour with a bit of attention. I know there are several really good concrete guys around these parts, I'm sure someone will chime in with suggestions as to the reasons and possible repairs as necessary.

 

[bmwguy]

Thanks @Riley

yes they used 2 trucks - so this makes sense it was the switch. The diagonal line is clear through both sides and a bit of a different consistency but not a gap or anything. possible below the door they took the wood blocking off too soon (maybe this is why the left the blocking on the right door for now), but I question if it matters. The entire interior of these walls will be filled with gravel so the fact that that section of the gravel base is filled more should matter no more than the clay soil in the middle being uneven, as it is only supporting the slab and not the building.

But I am no cement expert.

 

[bmwguy]

Update for this week - backfill is completed and all framing lumber and trusses have been delivered. Hoping the slab will be poured and framing will start next week.

Was back and forth on doing foam insulation under the slab decided against it. not doing heated floors and the added cost just didnt seem to make sense.

Speaking of heat - I am toying with the idea of putting a standard HE furnace in the attic storage room (I know I will need to heat the condensate line to prevent freezing and figure out where to drain it to. I like this idea better than a standard unit heater in corner of the garage. The only downfall of doing this that I have read is dust buildup on filter but may not be a huge deal if drawing from ceiling of garage - curious on thoughts anyone has.

A few pictures of the progress:

 

[bmwguy]

Big week. The cement guys poured the slab on Monday (5") and walls went up today. Trusses should be up by Friday.

 

[bmwguy]

Been busy working on the garage so another overdue update but great progress.

Framers and roofers were able to quickly finish the rough carpentry. I am overall very happy with the quality of the work.






The upstairs storage area turned out larger than I expected, so need to think harder about shelving plans up here



The wet attic flooring below was just from the first night with no shingles. We also had to order more of the plywood. Thinking I may paint or even just put a poly on the floor so i have some sort of coating.



Below is a more recent photo - all of my electric rough in for the building is complete. Ended up running about 12 circuits. A little insane but wanted to future proof. A few details-
- Probably 30 outlets in total. was thoughtful to have lots around workbench and in charging area where I will hang my bikes. Plenty on back wall, sides of garage and 1 on each outside wall. This is separated into 4 circuits.
- 2 6ga runs for electric car chargers or other heavier usage on each side of panel
- 10ga outside run for AC unit
- 10ga run to outlet in workbench area for 220a compressor, welder, other future use
- For lighting have roughed in:
- 3 LED cans in each bay
- 2 LED strips in each bay
- 2 LED cans in the workbench area
- 1 LED strip in the workbench area
- Ceiling fan in workbench area
- Ceiling fan between the bays
- Upstairs furnace circuit
- Upstairs circuit for lighting and outlets that can be expanded later



Also started to dig the trench to run the electric from house. I was going to have new service run but the utility company is backed up and i cant rely on them to install in a timely fashion. Plan is to run three #3 wires and one #6 ground in a 1 1/4" PVC so I can easily have an 80a circuit delivered to the garage subpanel. I am working with about a 50' run of wiring from the house panel in the basement. Need to get down another 6-8 inches on the trench to get to required 18" depth- fun stuff. Also picked up 4 8' ground rods and pounded those in - also fun. The house only had a piece of conduit of unknown depth for ground previously, now both buildings have 2 copper ground rods.

(the romex on the ground is for temporary power)



Tomorrow my framer should be stopping by to install the windows and service door.

I switched siding order from board and batten to 4x8 4inch OC grooved LP panels to match the house more closely at the strong recommendation of my architect. I wont be having the siding installed until around October.

Expecting the insulated garage doors to arrive early Aug (I think I ordered in May!), will be good to get the building secure.

Also been doing a lot of research on flooring coatings and insulation, which will be the next step after this phase.

 

[bmwguy]

also picked up this vintage 1977 Kenwood amp for garage tunes

 

[ScottW]

Thanks for the update! Interested in a few upcoming things you mentioned- heating types, upstairs storage flooring finishing, garage flooring covering options, etc. Please let us know what you are thinking, I have some similar decisions to make soon.

 

[bmwguy]

@ScottW - just looked at your thread. Awesome project and great view you have there. To answer your specific questions on my current thoughts:

Heating - originally I was going to do a unit heater in the corner, basic one like I have in the garage attached to the house. Advantages of these are they are cheap, easy to install, heat up very fast. As I started feeling out and thinking about my space more, and realized how much space I have in the attic / loft, I thought a regular 80k or so BTU furnace up there may make sense. Can get one for less than 1k and it will be out of the way, quiet, and I can have multiple returns / supply vents. May not be able to blast it to heat up quite as fast as the unit heater but this likely wont be a huge issue. Added benefit is I can also add standard AC and plan on roughing in the lines for this.

Storage flooring finish - I am finishing nailing it down the next few days so I will think of it more and maybe sample a few options. May just do a paint, not sure.

Garage flooring options - I talked to forum sponsor garage flooring llc and think I am going to do the TruAlloy urethane with a light flake. on the fence if I will fill the joints first or not. https://www.garageflooringllc.com/trualloy/

I was considering densifier / sealer but I think I would need to polish to get that right. I could also do polyurea but that seems like more work is slightly more money. The TruAlloy just seems like the best option for me.

 

[ErickForest]

The project looks great. Very similar to what I would like to do in a few years. Nice roof line, verify similar to out home.

 

[bmwguy]

@ErickForest - thanks. Nice modern home you have. Happy to share my plan files so you can see the detail that went into it. My architect was very careful to get the site placement / angle correct and also the roof line, we didnt want to overshadow the house. This is why I ended up switching the siding option to 4" OC LP vertical cedar texture grooved panels. The house itself is vertical T&G cedar 5" OC but that is quite an investment with lumber prices today.

 

[jarhead]

looks like it is moving along, going to be nice with having all that storage.

 

[bmwguy]

@jarhead - yes thanks.

In a bit of a slow period right now. Trying to finish electrical and get that inspected and need to order siding so it can be installed in October. For those following - I decided to go with 4 in oc LP cedar look panels and trim. Should match the house close enough.

Also decided to have spray foam on garage walls only. Will do batts on ceiling.

My overall goal is to be ready to install the overhead doors before winter and have everything sealed up. The door guys are going to use an 8 foot track for my 7 foot doors to accomplish a high lift.

 

[FstEdde]

Great project! Don’t rush it-you’ll regret it later. Enjoy the process…

 

[crepr12]

any updates OP....

 

[phred]

I really like the design. I also appreciate the hand drawn plans. Looking forward to more updates