Seek the assistance from a local architect that can see what you are talking about and will not have to try to drag the information out of you over the internet.

@Mark Bischak, Architect - these are two design options. now attached.

What is the purpose of this addition?

And bedroom 3 closet is unusable except for throwing things in.

The kitchen in the first one has no fridge?

The door to enter the space from the garage into the house is way too narrow.

An 18' deep garage is not long enough for anything other than a compact car. A small suv is about 168" long which leaves you with only 48" of space on either end of the car.

A Mitsubishi Mirage is 148" long which leaves you with 68" of space or just over 3' on either side of the garage. Nowadays 19' long is considered small.

Purpose is to possibly rent it out to students.

You're right on the 1st has no fridge - my architect is now figuring out another layout.

There will be enough space to hang clothes and etc.

18" deep -- assumed it would fit an SUV. Good flag.

So, you are turning a one family house into a two family house. Does the ground floor have it's own HVAC system and controls? Make sure the garage and the living quarters are well ventilated for gases and fumes and appropriate fire retardant walls.

Essentially... will be installing separate HVAC. Thanks for flag. Do u think 2Bed 2Bath works?

An addition like this in one of the most expensive locations in the US requires the services of an architect. Someone who forgets a fridge and produced those diagrams likely does not carry an architect’s license. Add in the extensive renovation projects in your other posts? Do not be at all surprised that a teardown is less expensive. It’s 7 figures. Plus, the zoning for a 2 family would need to happen, as private short term rentals are on notice for probable elimination for the future.

Good points; these were his preliminary drawings and I did engage an architect.

Know if I should ask for 18" feet or 20" feet garage length, instead?

I drive a 2018 Chevy Suburban, it is 18 Ft 7inches long. Now not everyone drives a boat, but that will give you an idea of how small an 18 ft garage is.

Our garage is 30’ deep, so there can be traffic paths and bench. People need to have paths through spaces. You can barely park in that garage. ,But once you do, you can’t get out of the cars and get into the house. There is no path to do so. That’s one of the BIG misses of the above. It forgets the room that people need to be able to move from room to room.

Reverse engineer this. What is your budget for changes to this home? Figure out what can be done for that amount. Then talk to builders about doing a teardown. All of the value is in the land in San Francisco, so the teardown option is usually head and shoulders above any other for creating value for the money spent.

latest drawing w: 20" for garage. thoughts on layout?

Your 2nd bedroom is 3/4 the size of your kitchen/living room space.

Trying to maximize space and really do want a 2Bed, 2 bath and to fit standard car. Hmm... what do u think of 19” feet long garage?

A total teardown and rebuild is pricer than this addition on ground level plus will require more time. Right now - just trying to lock down on design and move forward.

Thank you all...

There will be enough space to hang clothes and etc.

No there will not be because you won't be able to get into the closet.

People use their closets for more than just hanging clothes. They need room for shoes, bags, etc.

You may want to re-think this entire plan. what Is this addition going to cost you, and how much are you going to be able to rent it for? How long until you start to turn a profit?

If I was a renter, Id choose a full kitchen and useable closets over a 2 car garage.

The bedrooms in the second one are too small. A queen bed is 60" w x 80" long. That means that once the bed is in the room, all that's left is 60" x 40". That's not even enough room for walk around room or for a dresser in the bedroom. That's not even 3' on either side of the bed and only 3'4" at the foot of the bed.

A full size bed is 54" x 75". So that leaves 66" x 45". That's only 33" on either side of the bed and only 45" at the foot of the bed.

And the master bedroom only has a 4'3" closet? So where should the person staying there keep their clothes?

There is no living space. No place to put a sofa or even a couple of chairs. And the bedrooms certainly have no room for a chair so where are people supposed to relax?

And then having to do the laundry in the garage? Where will they sort the clothes?

So now you have 20' of length. That means if you have a 168" SUV, you have a total of 72" of space left over or 3' on either end of the car. So where are these renters supposed to stand when doing laundry? Squeeze between the car and the machines?

As someone else suggested if you insist on having a rental, make it a one bedroom so someone actually wants to rent it.

For the space here, it does not look like enough size for a 2 bedroom, 2 bath. I would go down to 1 bath for starters and see how that works out so that you can get larger bedrooms.

I can't imagine that the placement of the furnace and water heater in the last drawing is legal. It's certainly moronic to plan to drive a car past one or two gas appliances. That's just asking for a catastrophe. And how does anyone walk between the car and those things.

That little shelf in the left bathroom is insane. Get a ruler. Look at how narrow 14" is. now try to reach the shelf in a 3-foor deep hole!

There's no dishwasher.

Here's what's going to happen. You're building a very, very compromised design that nobody will want to live in for long. You'll have high turnover and the tenants will not respect the place. You'll get the tenants you deserve if you treat them like this.

thank you for feedback - back to drawing board.

How much is re-purposing space that already exists and is served by the two stairways shown?

How much in the way of floor space do you intend to add?

Show what you now have and then say what you want to add.

You show two stairways -- do both now exist already?

Is the laundry for your family or is it being built for the rental?

If you can create a solid wall between the rental room(s) and your home -- via full width hallway/mud room/storage/w/laundry within it and both a door to access the space from your interior and a door to access the outside from it-- space that will serve YOUR family/home, do. Then and only then build the rental space separate.

IF you are trying to create an "inn" situation -- renting rooms where you provide one or more meals for the renters-- you'd need only one center lockable door into the new space from the existing space. This setup could work for renting to strangers/students or for boomerang children or elder parents/in-laws.

..... You could create only a small dining room with skylights adjacent to that back hallway/mudroom of your home -- (accessible from your back hallway). Then creating two small bathrooms (one on each side of that small dining room). The small dining room would then be used by both the renters and would be accessible from each of the two rental rooms.

..... Each of two rental rooms would have private access to their private bath (situated beside the dining space) about 6' for each bathroom with a ten or twelve foot small dining room in between. In lieu of a large "den" That small dining room could become a shared meeting/sitting room with a table and two of four comfortable chairs -- a place not only for the renters to eat but visit with each other and/or members of your family and/or friends they invite in thru their own rooms to share a board game or card game if/when they choose to do so.

..... The two actual rental rooms would be a side by side equal sized pair of elongated rooms at the back end of the space in which the renter's own furnishings would "divide" the room into a bedroom area (adjacent to their private bathroom) and a small private sitting area at the back end of the room (opposite access to the dining area). Have the back wall of each of the elongated rental rooms be a window wall with a French door for private ingress/egress -- separated from each other as much as possible and with a tiny patio for each renter divided by a planter wall.

How long/wide you make the overall space would be up to your budget and intended use.

If the renter/students are family or close friends, you could also use that small dining table as a folding table for your laundry room and/or permit your renters to use your laundry room -- but you probably would want to be able to lock the door of that dining room from hour family side for security reasons..

Thanks for giving insight.

Laundry is for both rental and personal.

On set of stairs is for upper level while other stairs is from upper level to lower level.

Do you really need a two car garage? Can you utilize space form one garage for the interior? Maybe add a carport somewhere else for a second car if needed?

Who drives a suburban in SF?

Im sure very few. I posted to give a visual of 18ft. And when I posted, I missed the detail that this was in SF.

i Still can’t visually figure what this OP is trying to do, nor can I see why they would go through the expense?

Thank you both for input and help.

One garage space would be for me to park - I have a compact car. The other space would be for renter. I was envisioning the space for AirBnB / students (light cooking) from rental perspective, and if not for that purpose, then it would be for visiting family/relatives.

All had raised good points on the 18" feet long garage but it's also true that largest vehicle for me would be sedan. And, I want the garage.

Very keen on 2 bedrooms and 1 bath minimum - this works for extended family use and/or potential rental. But the flag on smaller garage is concerning. Wish I had a bigger place.

You can't squeeze 10 lbs into a 5 lb bag.

You really should read all of the stringent requirements for short term rentals before you go down this path. The registration process is an ordeal, and only getting tougher. They are very tightly controlled, and getting more limited every year. A build like this as an investment is pretty risky.

Who will be living here matters as to the (las) question.

Related to you.

Strangers related to each other.

Young people and/or elderly.

Since you're already considering a shared great room -- living/dining/cooking space -- have you considered putting only a full great room downstairs and putting any sleeping room(s) upstairs?

If you're renting to strangers who are young students, then expect them to provide their own dorm refrigerator, coffee maker, microwave (and, more dangerous if unattended ... toaster oven and/or portable hotplate) -- all you'd need to do is to provide safe cabinet space, shelving and countertop on which these items could be placed for use. Unless the two student/strangers are family to each other, you may well be better served just renting out two large, unconnected, rooms, each with their own full bath (shower, sink, toilet) and let them decide (from what you do allow) what they will add to their room. It may well be that college students have a meal plan at the college and will do little more than snack and/or brew a cup in their rooms.

Why would a college student rent a room like that when they can have a dorm that offers the same amenities?

Well for one thing, I have never seen a dorm with a garage - though I am sure they exist. I also have no idea the dorm situation in SF. It is possible that they don't have enough dorm space for all students. And there are always situations where dorm living isn't an option.

At least in a dorm room there is a place to put a desk in your room and a common room to sit.

^^^Which is more important than a garage.

May Lee, I would put less weight on the opinions of the people here, and more into research on what off campus college rentals are like in your area. How large are the units, how large are the bedrooms, what are the rents per square foot being charged? Are rentals more commonly by the bedroom or for the entire unit? What is expected in kitchens and common areas? What sort of students choose to live in your neighborhoods?

I would aim at attracting graduate students, as they are more likely to be focused on their studies, be quieter, cause less disturbances, and have a greater level of maturity, especially if the schools near you have programs in areas such as medical, law, or architecture.

From my experience in being a college student at an urban campus within the last 10 years:

1. Almost all graduate students in most of the US choose to live off campus, unless they are international. Many undergraduate students if allowed would rather live off campus too, because on campus living often either means sharing a bedroom and a bathroom and very little privacy, or you or your parents have to spring for the overpriced on-campus apartment style units. Living off campus is almost always cheaper.

2. As a college student I would never rent a unit without appliances. Unless it's expected that I have my own mini-fridge, and then there has to be a place to put it. Honestly as an adult I would never rent a unit without appliances, but maybe that is a regional thing. In fact, don't allow a tenant to have a hot plate, or space heaters, or anything else that could be an electrical hazard.

3. Most college students that I knew, unless they were really tall had a twin bed or full size bed. Queen beds or larger are a pain to move around, which college students frequently do. I've also had many roughly 10x10 bedrooms and they have worked just fine. Sure, the bed either has to be in the corner or closer to the wall than usual, but only one person will be sleeping in there (another note, your lease should have limits on the number of nights that your tenants can have visitors).

4. That said, the bedrooms should absolutely be designed so that each can comfortably fit a desk in addition to a bed. If your closets are setup well enough, these rooms don't need to fit anything else large. A student might have a small bookshelf or dresser, but they likely won't come with too many clothes.Or if they do, they will need to find themselves a larger more expensive apartment (back to what I said above about knowing your local market).

5. If I am a student and I am on a budget, I will absolutely compromise for a smaller unit if that means that I can get it for less. I have lived in my share of studios and tiny bedrooms. If your space is actually a little smaller than the typical in your neighborhood, and you charge a little less for it, that may work to your advantage.

6. Your common area doesn't have to be huge. If it fits a table for 2 a sofa and a TV, you are all set. My experience with common areas and students is that they actually don't get used a ton. And making them larger just invites large gatherings, which may be disruptive to you upstairs.

7. Is the washer and dryer available to the renters to use as well. Having done it once, I would never again rent a unit without laundry in the building. No one wants to cart their clothes a few blocks to the local laundromat in the rain because that was the only day available to get it done.

8. A dishwasher is really nice to have, but I have rented many apartments both during and after college without them. This is another case where I would see what rentals in the neighborhood have.

A couple thoughts on your latest plan:

1. The closet in bedroom 2 being 3' deep is just wasting space. I would make it a more standard 25-26" deep and give that space back to one of the bedrooms.

2. I would mirror the bathroom/closet design of bedroom 1 so that the closet is away from the door and can have a full width bifold door. That will make it more useful.

3. Rethink the shelf in bedroom #2. This should either be a small closet or cabinet facing out into the hall, or delete the stub wall next to it and make this a full height wider cabinet next to the vanity.

4. I second that the furnace as located in the garage is just asking to be hit and banged into, since it hangs out into the garage door. If you have a small car, are likely to always have a small car, and the average buyer in your city also has a small car I would make a dedicated utility closet at the end of one of the stalls, leaving the other side longer for larger vehicles.

5. Most importantly, I think the common area needs another revision. The kitchen is wasting space in the corner, and there isn't a great way to layout furniture in the rest of the space. Maybe there is a way to get the kitchen back on the wall by the stairs, except the refrigerator? I would do a 24" electric stove and 24" refrigerator/freezer combo with a 24"-30" lower cabinet for storage and workspace. If you don't have a dishwasher I would try to fit in a small double basin sink. Upper cabinets should be generous and extend to the ceiling if possible. Try to then get two opposite walls across from each other that are clear to place a sofa and TV.

Is there any room to build out? I feel like if you just had a little room you could do this. I suspect that May Lee lives where parking is a premium and adding a garage adds value to her house.