I would not want to buy that house. Your kitchen/living area is a cave. Very little window for that amount of space--seems like a waste of the lovely climate you live in. A few other practical notes:

• You plan to have children in the future. When you have young children, you want your bedroom to be much closer to their bedrooms. That looks like a nice amount of privacy for parents of teens. It's a really long hike when your toddler is howling at 1 am and you want to tuck their blankets back up around them and get back to your own bed.
• Bathrooms should always have exactly one entrance. Two entrances means an embarrasing walk in. Or an inconvenient hike to the other side to enter and unlock the door someone accidentally left latched.
• If you are designing for a parent to live with you, design a room with an ensuite bathroom or closely adjacent bathroom that suits people with mobility difficulties. Your guest bathroom is not that bathroom.

I'm guessing that your lot size limitations are driving this design of a living area ringed by bedrooms. Is it possible to solve some issues by building up? You could have a nice guest suite and home office downstairs with only a small addition to the footprint, and generous family bedrooms upstairs.

No. No. No.

Your kitchen is doomed to be tomb. You needn't hear more than that. The patio doors to the light? There will be no daylight. Daylight, particularly a single exposure, is not penetrating light.

Tear it down and start over with a two story home, Kitchen , family, utility, guest bath, MIL , small office on one, ( join a gym ) and all else on two.

Or look for a home that meets your needs..........on a lot NOT deep and narrow.

The only way to double square feet on this? Go up, or buy out the folks next door : )

I have no idea of the house but IMO 1950s homes were often pretty cool and you post no pics so no idea about yours. First you do not know what you are doing so hire an architect to even begin to double the size of a home. Can it be done on your lot? The best way usually is to go up not out if the budget and lot are tight but You need to know what can be done and we have no clue , At least post a pic her eof the house far enough back so we can see the lot too. Post all things to do with this subject here in comments DO NOT start another post.

Alll of the above but walking in the front door the wide entrance to the right goes to an office, look left you get a jack and Jill bath which is the primary bath for guests (no one likes a bath with two doors, especially right by an entrance) and straight ahead you get to walk through the kitchen. Not good.

Sorry to pile on.......and then you traipse through all the family room furniture to grill on the patio at the large and lovely "back 40".

No to that too.

You have a large budget that will be really wasted on this layout. Please spend time interviewing architects, asking neighbors about their renovations, and spending time really finding a great layout that works. Look on Zillow at other renovated homes in your neighborhood that may have begun with the same house you currently have.

You have so many chopped up small rooms. The primary closet is the same size as one of the bedrooms. Odd.

Who is going to run to the guest bathroom at the front door when they are hanging out in the backyard or in the living room? Nobody. The other bathrooms will be used by guests.

Think of aging in place with your mom. Give her room to ambulate in a generously sized bathroom.

Your kitchen and living room should run along the back of the house opening up on to the backyard where you spend a lot of time. Having it in the center of the house leaves no light. That great backyard view is wasted on a bedroom for one person.

Whatever you do for your day job - could someone do it with no training? While I understand this is your home, so very personal, and you have ideas about what you want, you need a professional architect for a project of this magnitude. We put an addition on our previous house that only increased the square footage by 10%. I just told the architect what I wanted in general terms (the problems that I thought needed to be solved). What we ended up with (after three iterations - which I do not consider to be excessive) was perfect and when we sold the house the buyers specifically mentioned the addition as a factor in their desire to buy the house. You cannot hope to achieve the best result without professional help.

I’m not a pro but I’ve designed and renovated several homes while lurking on Houzz. The biggest problems I see with your floor plan are that both entry traffic patterns go right through your kitchen and your secondary bedrooms are still very small. There’s also no separate kids space/play room for your future kids to spread out to as they grow so those small bedrooms will feel even smaller with toys or desks packed into them. I assume your mom’s bedroom would be in the storage/gym area but she’d have to share that bath with guests and access the bedroom either through the shared bath or through the mud room, which isn’t ideal. The kitchen is massive but anyone sitting at the island would be facing a wall rather than the entertaining space and yard.

I’m currently in the midst of a full gut remodel on my own home, turning it from a 1200 square foot 2 bed/1 bath home into a 2600 square foot 4 bed/3.5 bath home so I know how difficult it is to rework an existing space. In my case the additional square footage came from building up and adding a dormer to capture previously unusable second floor space. Is there any way you can build up, even if it’s only for your master suite or the two kids rooms and a bath? You may find it’s more cost effective to stay with the existing footprint and build on top rather than enclosing your patio and converting your garage to living space. By adding those spaces to your interior you’re creating a pretty square house, which means a large windowless space in the middle no matter how you lay it out. Look for cpartist’s posts for a very detailed explanation on the importance of a house’s shape in its design and layout.

If building up isn’t an option then I’d try to find a way to reorient the kitchen so it’s not a traffic path (turn the island 90 degrees?). I’d also close off the door into the bathroom in the entry so that is private to the storage/gym area and relocate the other secondary bathroom to between the bedrooms. That bathroom is then in a better spot for guest use and equal distance to the secondary bedrooms. Pushing the middle bedroom down also makes those two bedrooms more similar in size so your kids won’t fight about who gets stuck with the smaller interior room.

It can be very discouraging to have your dream project criticized and torn apart, which is why I never put my floor plans up for review and rather lurked through all the floor plan posts to gather and experiment with ideas. I went through about 50 different iterations and several packets of tracing paper over 7 years before finally deciding on the plan that worked best for my family. While the final plan isn’t perfect it allowed us to keep much of the original structure while enlarging and modernizing it. Best of luck in finding the right layout and getting your project off the ground.

Even a good addition plan (which that is NOT) will leave you with the old small rooms with the old ceiling height, and all of those issues. You really should explore that teardown. Because what your plans say is that you really want a new house.

Three years "planning"......."agonizing" and hard no comes back at you.

But the red flags, the hard no? May have saved you a trail of tears, and a river of money.

You're young and there is plenty of time. Don't get discouraged, just start over.

The room where you will spend the most time (the kitchen) has zero windows. That alone makes this a bad layout. Even if the family room faces south, the kitchen will be dark, and even darker if the family room faces some other direction. So yes, the kitchen "cave" is a hard no and a very red flag.

If you are limited to a square i would build up. no way would i spend that much money on a house with such dark common spaces. with potential for kids plus MIL i’d want some separate common area space as well. Doesn’t need to be big - i have 1400 sf 3 br with eat in kitchen separate from DR/LR so kid can be watching something and i can listen to music and cook.