SFGate

Ironwood Builders Your plan is not labeled with bedroom and location of the tree! Where can you add on? Generally, the smallest bathroom, shower or tub regardless, for a full bath, is 5'X 9'. Traditionally, we can get a lavatory, toilet and shower or tub in that space, while still getting a window and a door into the room. Less room means smaller... And codes require certain distances... 24" in front of the toilet, 15" from center of toilet to wall or cabinet. 30" minimum width of tub or shower. California is strict that way. Variances are granted for alternate materials and methods... But it costs $$. I've been through the process in Sonoma County. I spent 40 hours or more, plus several hundred in fees to get very little done. And they actually like me at the County!

nvcowgirl Thanks, Ironwood. I appreciate all the numbers -- those were some of things I didn't know.

You're right, I forgot to put in the tree (it would be at the bottom right of the plan, 10 feet straight down from that back wall). The max I can add on to the back of the "master" is about 5-6 feet, putting the new bath backing up to the existing one. We get no additional bedroom space by doing that, so it seems like a huge investment & hassle for very little return in the way of space. I keep wondering if I can capture space from the kitchen, taking out the back porch and moving the kitchen over. We can go back from the kitchen with no problem, lots of space and no trees there.

Interesting that you're in Sonoma. We've been looking at property up there as an alternative to doing the remodel here, but that complicates the commute situation (to SF), which right now is easy via Caltrain. This is ... the joys of old houses.

Ironwood Builders I know a great realtor and the ferry boat captain on the Sonoma! Wine country is incredible. I have you in larger format now...was on my iPad and couldn't read your room labeling. Cost will be driven by proximity to existing plumbing. I doubt the kitchen has the 3" minimum soil pipe to collect the toilet effluent...so some big expense there...that you never see, but are really grateful for. Water lines are not the problem. Not seeing how you add on to the kitchen though. The cellar stairs look to be in the way and losing windows?? Plus giving up closet space from the master? Kitchen is probably big enough not to add on to and still be adequate. Just hate giving up storage space in a pre-war.

LEONARD MANNO | ARCHITECT Hello,
i am a very big fan of old homes and usually i suggest to keep them the way they are...but do to the lack of information, i can suggest this idea (see picture), an extension of the kitchen over the cellar stairs and to the right a bathroom for the master bedroom.
this will avoid you any work inside the house, for example you can simply transform the window in the bedroom into the door for the new bathroom. hopefully the new piping can work out fine with this idea!
good luck, Leonardo

nvcowgirl Leonardo, we've owned this home since 1987 and have always been reluctant to make even the smallest of changes because it is so charming just as it is. IF (big IF) we can figure out a way to do this and keep it looking original, we would go ahead. Yes, extending over the cellar stairs is one direction we have explored. Your drawing matches pretty closely what my husband last proposed. It's nice to see it drawn out. The back of the house is pretty plain and this would give it some punch
Thanks for the input. I attached photos of the front and back of the house, just for fun.
Joyce

LEONARD MANNO | ARCHITECT Hello Mrs. Joyce, i am specialized in historical building preservation, this the reason for my conservative tendency. I believe that investing in the preservation of our cultural heritage would prevent cultural bankruptcy in the future!
The pictures are very helpful, and still confirm my suggestion! I can add, that the extension should not blend in with the rest of the home (material wise). instead it should be evident and clear, from the outside, that it is a new addition! Maybe, by using a different material for the exterior finish!
Leonardo

Ironwood Builders Looks like it will be on the back of the house anyway! My time in Historic restoration and additions agrees with Leo. Perhaps using the siding shown on the front gable will work on the addition? Just the roof material and trim could match. Is there enough headroom over the cellar stairs to keep them functional? Are they able to be constrained within the footprint of the new foundation?

nvcowgirl Yes, the stairs fit inside the addition (this is one reason we'd like to add the new space, so we have indoor access to the basement). Nice idea about using the gable trim on the new space. The headroom on the stairs is an unknown right now -- they currently have no impact on the interior of the house, but the headroom is probably not up to code.

We are scheduled to have the old foundation replaced (just the perimeter at first, not the stairs) to solve settling problems and to add seismic upgrades. In a second phase, we will have them replace the stairs. I wanted to get my add-on design sketched out because it could affect the location of the stairs.

I am liking this more now that I see how to do it without changing the bulk of what's inside the existing walls.

Construction Services here is a quick sketch about ways that you could lay out the bathroom, 5x13 is plenty of space for a bathroom. you would be looking at about $13,000 for the rough construction cost plus probably another $10,000 to $20,000 in finish cost including materials like tile, plumbing and electrical fixtures. Give me a call if you would like me to come out and give you a free estimate, I am glad to help.

eeclean If all you are trying to do is create a master bath, why not remodel existing bath to open into master and create a new powder room by front entry using coat closet as entry taking over bedroom closet and build new bed closet to left of 2' protrusion into room.