Thank you @3onthetree! Some of the ideas you have expressed are thoughts I had not thought of!.

I checked with the city and 1200 sf is allowed with setback of 5' in both sides. The height should match existing house. I already have sewer, water, and gas in the backyard. The lot is flat, so no hillside to deal with. A little slope toward the back of the back wall (about 8") for the 80' depth between the house and the back wall.

In the future, that building _could_ be living space (3 beds, 2 bathrooms?). The chances of being living space are slim, but who knows the future.

Thank you!!

The utilities present is thinking in terms of the building does not want to be placed over your electrical or sewer lines to the main. That would be a large expense to move them. Also, you may have bigger setbacks or easements on your specific lot beyond the standard 5' for your zoning classification. It is good to get at least a site planning survey performed if you don't already have one or have no stakes for the corners of your property. (usually for permit it is required).

Unless your AHJ allows "coach houses" a separate independent habitable structure usually is not allowed on the same lot.

Option 2, because with option 1, the stuff you store will be behind your car. If your garage is stuffed, squeezing around your car will be tough. You will also want a door on the left side, to allow you in to the storage, without the car in the way.

That said, how easy is it going to be to back in or out of that garage? I'd consider lengthening the existing garage. Two cars front to back is a bit of a pain, but not awful. It prevents you from putting a lot of ugly driveway in your yard. You can build a shed for more storage where you've planned the garage. That way, you get more storage, but don't need more driveway.

@3onthetree Many thanks for bringing this up. I would be in deep trouble if I gone with the design permits then find out about the main electrical wire.

I never thought about the main electrical line. I just realized that the main electrical line is buried in the backyard all the way to the back wall. I did bury the main electrical 5 years ago, because I did not like the overhead wire going across the backyard. Due to lack of my knowledge I never thought about the scenario of having 30' wide garage. Lesson Learned :(. Now, I have to shorten the width to 23' so I do not build over the main electrical line. I do not think I am going to reroute the electrical. It took Edison 3 months when I did this project. I had to do the digging of 3 feet deep and run the conduit. They required 2 90 degrees bend only.

@Sigrid

Thank you for your feedback and suggestions. I do really appreciate it. I thought about going forward with the main garage. Actually @suezbell suggested going 12' forward and 12' backward for the main garage.

Of course I got different feedbacks, and I decided to utilize the backyard, since I already have driveway all the way to the backyard gate.

Here is the link to the thread:

https://www.houzz.com/discussions/5976293/garage-extension-forward

Thank you!!

I looked at your other thread, and have to say you need to start from scratch. Take most of the comments in the other thread with a grain of salt, if not outright disregard them. Commenters have fun spending other people's money to instill their own ideas of some design theory that matches some holy grail photos they've collected across the internet.

When you start with an architect, they will zero in on your space needs and desires for the house. They will pass those through the lens of a budget. If you want to maximize your ROI in the future, that can also play in the equation of what you do now. They will evaluate what is existing to determine the best route to accomplish all of it.

I could be reading between the lines of your comments in both threads too much, but it seems you have moved from a garage addition to the front, to the back, and then a detached garage (although a shed might still solve your problems) without the evaluation and decision making this requires.

Seems like your new garage is going to be almost as large as your home! I’m also for option 2. Absolutely. Both because it provides you with extra space to turn your car(s) around and because its entrance door seems to be more convenient. A roll-up door is also a great idea, I’ll think of installing one in my garage as well. Also (in case you are still in search of further ideas on how to build an ideal garage), you can separate the storage space from the rest of your garage with kind of a curtain wall (e.g. like this https://www.curtain-and-divider.com/industrial-welding-curtains/ ). It will protect your belongings from dust and is easily removable in case you change your mind. Good luck! Don’t forget to post a photo of the ready garage to the forum!

@3onthetree Thank you for the insight and feedback. I do really appreciate it. My brain hurts from thinking about this addition. My first plan was to go forward with the main garage 24'. Then plan changed to 12' front and 12' back, so the addition does not stick out too much. I found out it will be costly doing the 12' front and 12' back addition. Here is California, is it very expensive. So, I thought of just doing detached garage, and later on, it could be living place (Accessory Dwelling Unit). My thought, I would build in the 1200 square feet in the back as garage with 2x6 outside framing, so it is easy to convert to living space. In the future, that garage could be converted to ADU. Besides, I think it will add a value, if we ever decide to sell the house given the shortage in housing here in CA.

Again, Thank you for the insight and feedback. Have a wonderful day!!

If you've come to the conclusion, based on your pocketbook, patience, and realtor's current and future market assessment, that going beyond the need to store your son's equipment is a good choice right now, then great. I was just hoping you hadn't been pushed to that route because some commenters are against a front-load garage and call it a "schnozz" with no evaluation of space needs, the plan, or site conditions.

@3onthetree Thanks again. I am leaning toward doing the garage in the backyard with specification so it is easy to be converted to living space (stud size), have a bathroom, stub plumbing, vapor barrier. Later one, just add the walls, windows and finish everything else (If I need to). I will check with the city to see what needs to be done at this point, so in the future is easy to convert it to living space. Here outside wall must be 2x6 for living space, otherwise, you need to extend the 2x4 and use spray foam (which is expensive compared to just regular insulation)

Now, I need to figure out where should I put bathroom for the 23x45 garage, after I found out about the main electrical wire that your brought up earlier :) which changed my plan from 30x40 to 23x45.

Thank you. I do really appreciate it. You saved me a big headache by pointing out the main electrical wire....Thanks again

Have your needs changed since the earlier thread? I need more garage space, since the current garage is occupied with my son's sport equipment and bikes. I can hardly park one car in the existing garage. The existing garage is 17' 8" wide x 20' 8" deep.

@partim No, I still need more space.

I am thinking of something like this, without the kitchen and the apartment up stairs. Garage + bathroom + Storage.

http://www.garagewithapartment.com/wp-content/uploads/2011/03/g384-Garage-with-Apartment.jpg

To decide on: 23x40 or 23 x45. Have not decided yet.

Location of the bathroom, in case I need to convert it to living space later on.

Thanks,

What I meant was, is your only need right now for sports equipment storage? If so, add a sturdy lockable shed for one tenth of the cost that you're talking about. Not to mention the stress and aggravation of permits and building, and making decisions for the future hoping that you'll get your costs back one day.

Hello everyone,

Thanks everyone for the feedback and suggestions. I do really appreciate it.

Any suggestions on the location of the bathroom in the 23 deepx45 wide garage shown above?

Thanks,

If you are really future planning an ohana unit, it may be worth moving the electric line. There is no 23 deepx45 wide shown above and your Options at the start are switched now, so it's hard to pinpoint the bathroom.

@Christopher CNC Sorry, I forgot to add the new drawing. I narrowed the garage to 23 feet instead of 30 feet. the Electrical main will be 2 feet away from the garage. The Arrow points to the north direction.

The sewer cleanup is to the right of the electrical main (1 foot a part)

Regarding moving the electrical line, I am still investigating.

Thank you.

Put the bathroom in the back right corner.

First 25' both sides - living - kitchen - dining.

Back 20' - bedroom - open office - bath

Back left side 20L x 15W bedroom

Back right side 20L x 8W - office front - bath back

Garage door is front door.

Left side door between living and kitchen

Bathroom in back right corner good for car parking and storage.

@Christopher CNC

Wow, that was quick. I do really appreciate it. Are you an architect? Can I fit two bathrooms in this layout? I really like the idea of the 8 feet office....very clever.

Thanks,

Not an architect. I live in a tiny 16W x 27L house with a 16W x 10L loft above the back 10'.

Two bathrooms? Don't be greedy. You can make a nice 8x 10 bath with that open office space combo.

It would be wise to locate your sewer line all the way to the main. Is the cleanout you are talking about outside next to the house? Seldom do sewer lines run perfectly perpendicular to the house like you've drawn it. And is there gas?

@3onthetree Thanks. we redid the whole sewer lines in July 2020, and I had cleanout in the backyard for future expansion. It is 1 foot to the right of the electrical panel, so it should align nice with the outside perimeter of the 23x45 garage (going north to south direction) . I also have gas line by the gate.

Thank you for the feedbacks. I do really appreciate it. I am learning as I go, so I really appreciate feedback, suggestions, knowledge and experience that this forum provides.

Fair warning. Curve ball ahead.

If your are seriously future planning an ohana unit, I want to move the entire garage. Move it to the back left corner of the lot, left of the electric and sewer. Make it big as you want or code allows over there. Maybe even two bathrooms.

That arrangement is even better for cars and long term parking.

@Christopher CNC

Just for clarification. The sewer line does not run across the backyard like the electrical main. I have cleanout at the house back, so I can easily attached the sewer line of the garage to it.

If I move the garage to the left corner, I will have no more backyard, because the driveway will take the whole backyard with the turn.

Can I have two bedrooms, 2 bathrooms in the 23x45 sf area, or it is too tight?

Thank you.

You can have two camper size bedrooms and baths in that space, a smaller kitchen, living and no office for you. Where are the tenants going to park their cars once it is no longer a garage? A well designed parking court could also be a lovely back garden patio.

Thanks @Christopher CNC

While you drinking your coffee, can you please do a quick sketch of "A well designed parking court" that you mentioned, so I can see what you're thinking. I am here to learn.

I doing the research before I meet the architect, so I am ready when I meet him.

Thanks!!

Back to sewer, the depth is what is important. If it goes out to front, the high point is at the back of your house. If the depth, using 1/4"per ft slope, to get from the new garage with bathroom at back, all the way to the house, does not meet up, that's an issue. So estimate 70' length would be about 18" depth. If the depth under your house is deep below your slab, then they can tie in.

There is a picture of a well designed parking court behind the house on a lot that looks narrower than yours on this thread. Currently the last comment. You could google that as an image too. There will be no quick sketch.

Ideas for widening driveway (houzz.com)

3onthetree Thank you so much. I will be busy doing measurements this weekend to make sure I am covered.

What happens if I do not have the enough 18" difference? Do I just add gravel to raise the floor level of the garage? For house, I would do raised foundation instead of slab. I am not sure about the garage. I need more researches.

Are you in the construction industry? You bring up things that I will never think of. You caught the issue with the electrical, and now I am investigating the sewer.

Again, thank you so much!!

Hello everyone,

I did the measurement for the sewer line. The bottom of the cleanout by the house is 16" below the grade. From the house to back wall (South side) is 80 feet. From the house to end of the garage is 75 feet (5 feet setback). So I need at least (1/4" x 75) = 18-3/4". Will this be OK? If not, what is the solution? The option is using a pump is out :). since I like gravity to do its thing.

Thanks @3onthetree for bring this up. Please keep all the great ideas and the things that I am not aware of coming.

I setup appointment with the electrical company to see how much for them to pull new wire, if I dig the 3 feet trench all way to the junction box which is located 1 foot from the back wall (South West corner)

Thanks all for your suggestions and help. I am learning a lot.

Will this be OK?

I don't know, brought it up as a constraint in the design layout. There are other things that determine if you can tie into the line, like the exisng size (is the cleanout at the 4" vent stack, or end of a 2" line?), the slope at back yard (higher or lower?), the finished elevation of the garage slab, the thickness of that slab, the elbow at the toilet/vent stack lowering the line below the slab, etc. You may find the depth of the sewer line at the front of the yard is much deeper, so maybe the garage line runs outside the house, past it to the front yard and connects closer to the street main on your property.

Thanks @3onthetree

The clean out is 4" pipe all the way to the street. The backyard slope difference between the house the back wall is 8".

Going all the way to street will destroy my driveway which about 80 feet long of stamped concrete that I spent lots of money when I did it.

How do you normally increase the elevation of the garage? Do you just add gravel, dirt, increase the slab thickness? What is the preferred option?

Thank you for you insight. I do really appreciate it.

How do you normally increase the elevation of the garage? Do you just add gravel, dirt, increase the slab thickness? What is the preferred option?

You set the elevation based on the existing grade and drainage characteristics (if you are not altering them). The function and design also plays, as a garage should be closer to grade. If you need to raise the elevation for some reason, for smaller heights you usually do it with a thicker gravel base.

If you are debating to raise the garage so the waste lines meet, I am not aware what code says about minimum cover for the sanitary line that would be traversing your backyard.

Hello everyone,

Thanks to @3onthetree and @Christopher CNC for the continuous feedback and suggestions. I do really appreciate it.

After doing some research and talk, we will run the sewer from the front of house to get the right slope. Here is the latest drawing that I did, before talking to the architect. The bathroom will be in the south side of the garage. I placed utility sink, as reserved spot for future kitchen sink if we ever decide to convert to living space.

I placed some windows. I was not sure where should I place the windows, since the layout of the rooms is not determined. I used the floor plan in the link below as a guideline. I would like to make it easy in the future to convert to a living space.

Any suggestions and feedback are welcomed regarding the replacement of the windows and bathroom. I based the layout on plan 45269 (Reverse the plan, and remove garage):

https://www.familyhomeplans.com/plan-45269

I am not sure why one of the bathroom without a window. I love natural light, since I sit all day in cubical with no windows.

Again, Thanks for the feedback. I am learning as I go.

NOTE: Please see option 1 at the beginning of the thread for the site map.

Move the bathroom 4' to the left so the door is not blocked by a parked car. This will also give you a bigger back bedroom. Add another window on the back wall of the kitchen and make the window over the kitchen sink bigger. I want a sunny kitchen.

Thanks @Christopher CNC.

I have to be careful where the windows in the kitchen, because of the cabinets' location. Here is the latest version with your suggestions and my tweak.

The whole objective, it to make it easy for us when talking to the architect, by getting feedback and suggestions for the forum members. Hope this will speed the decision making process.

I know it is hard to design truck to be a car in the future, but I am doing my best, so the conversion to living space in the future in easy (it is every happens). I see most the garages without windows.

Again, Thank you for your time!!.

I might add another 4020 windows in the master bathroom and rotate the sink in the toilet, so you do not see them from the living room (but your will see them from the garage door...oh well).

Seriously, do you want or need 3 bedrooms in 700ft2? Is that the kind of tenants plural you want? With 2 bedrooms you can gain a lot of the hall space for bigger rooms and STORAGE!!!!! People have lot's of stuff.

My next edit is to make the bathroom 10' long/deep. Linen closet. Better back wall for the kitchen. More privacy.

Don't like the kitchen layout. Put the sink back where it was. The left and back walls are for the kitchen layout. Not the bathroom wall. Nobody wants to listen to that while they are cooking.

Yes the plumbing for the bathroom and future master bath should share the same wall.

@Christopher CNC

Thanks. It is 1200 square feet, not 700 SF. I was showing the future layout. The garage will be build with one bathroom and one utility sink.

You are making a good point about the kitchen location. I was thinking table will be on the left side of the kitchen. Also, having the sink in the same wall as bathroom, will make plumbing easier.

Thanks for the feedback.

Me bad. Yes 1200ft2. I was thinking Maui ohana unit. Alright. You can have the third bedroom.

Sharing the two baths plumbing would be better than a bath with the kitchen I think. Plumbing is where I got my lowest house building scores though. I just know they are fussy about the toilet's order in the line. That's a plumber question. I'm a gardener.

Here is the latest with the wall. I am sure the architect will make it more pretty, but this just sketch to get feeling for the layout. I forgot to put windows in the rooms...oops. Thanks

Going back to a previous idea about relocating things, you really need to consider how cars and parking are going to work when this is a 3 bedroom house in the back. You might have to cough up your existing garage on the left side of the house.

Yes I want another window on the back wall of the kitchen. Hope there is a nice view out back.

@Christopher CNC

Just for clarification. This 1200 square feet will be built as garage first. In the future, it could be converted to living space. The garage will have one bathroom, the one on the left, and utility sink (left wall).

The back is 5 feet from cinder block wall. In addition, adding a window in the back will limit the space for the cabinets in the kitchen (In the future).

I am attaching google map to get feeling for the space. I could not write inside the small box for the rooms and bathroom. I wrote the label for Living, kitchen and BA

As you see the kitchen wall where the sink is now, will face nice backyard. The back wall is 5 feet from the cinder block fence. I choose the Living and kitchen in the EAST side to get the view of the backyard. I hope this makes sense. Sorry about the confusion.

I do really appreciate your time and feedback.

Ok I'm good. Looks like there is room for 2 parking spaces between houses and a back turn around on to the drive. Might as well have a cabinet instead of a view of a cinder block wall.

So this started as a garage to store your son's motorcycles. Even if the ADU allows 1200sf, do you really want a 3 bedroom in your backyard (your house is 1484sf)? That means a bigger family (4+ people), more outside space needs, more activity, at least 2 cars, more coming/going, more noise. If you had a terrain like a hillside where the ADU is more concealed that is one thing. Here it seems you would be on top of each other. I don't know if maximum SF on an ADU would equate to maximum resale value in this case. There was a recent thread for a pool house in SanDiego to be flexible for an ADU, earmarked for a traveling nurse or similar professional which would be less intrusive. Basically the size of a 2-car garage.

@3onthetree

You are making a great point. I do really appreciate it.

The allowed ADU is 1200 square feet. It was 800 SF, but changed to 1200 SF in year 2020

This will be build as garage with one bathroom (1/2 bathroom), utility sink and windows . In the future ,it could be converted to living space. If it ever get converted to ADU, no stranger will live there. I am not planning to rent it for income, like what is happening right now in Los Angeles. If it does not get converted, it will stay as a garage. If it get converted, it will family only.

This garage is 40 feet from the house. I thought about this way. If the max allowed is 1200 SF, why not building max size right now, because the cost between 800 and 1200 is not that much. I might be wrong, and that why I reach out to the forum for feedback and suggestions.

Can you please share the link for the San Diego pool house? I do search to see if I can find the thread.

Thank you. I do really appreciate the insight that you bring to this forum. Have a wonderful weekend.

Here is the thread about another ADU, It's more about figuring the priorities, then designing for that. www.houzz.com/discussions/6071144/layout-for-dining-living-in-adu

In your case, you're are right about 800sf vs 1200sf, might as well. But, 1200sf is quite large (for habitable space once you overtake the garage), so having 1 bathroom for a 3bed (4-5 people?) is not optimum. I'm looking at it from the main house perspective. The bedrooms are overlooking this ADU and the outside spaces will be somewhat intertwined, whether family or strangers. If the existing house had a different footprint, I might maximize ADU size, but here, I might stick to just a 2.5 stall garage/1 bath/covered porch now, future 2 bed/single car stall. I wonder what taxes on a 1200sf ADU addition would be when your house is 1484sf.

Thanks @3onthetree for the link. I was planning to have 1200 SF with 3 bedrooms and 2 bathrooms (not one) OR 2 bedrooms with 2 ADA bathrooms ( in case we end up living there and my son lives in the house. I like this layout: https://www.danville.ca.gov/DocumentCenter/View/5439/Brochure-for-Craftsman-2-Bed-2-Bath-1000SF-PDF?bidId= ) . very nice layout for ADU in the corner of the backyard.

What is the size of 2.5 stall garage? 24x36? If that your house, how would you layout the garage with the one bathroom and windows? Simple sketch will help a lot (pencil and paper is cool too). The 1200 SF ADU will almost double property taxes. But for garage, I just need to pay the school district based on the area, about $2000 and $1500 permits.

Thank you for your help and insight. I really see your points and I am learning. Too bad, I do not have experience in construction.

Hello everyone,

Thanks to @3onthetree and @Christopher C Nc for the continuous feedback and suggestions. I do really appreciate it.

Here is the latest, before I give it to the architect (If I can find one) and structural engineer to do the calculations.

Looking forward to suggestion and feedback. Thank you

Hello everything,

After thinking about what @3onthetree brought up regarding having big living space in the backyard ( 3 bedrooms, 2 bathrooms). We decided to just use about 640 SF for living space and rest as garage.

Here is the latest layout, that I think will be good for one bedroom. Suggestions and feedback are welcomed, and you are not going to hurt my feelings. I have an appointment with the architecture in 4 weeks (Busy).

The garage door will be in the lower right corner. I added some windows to get some natural light.

Pardon my drawing skills....

Again, Thank you. I really appreciate the time you take to look at my layout and provide feedback. Thank you!!