Great feedback above. A couple things come to my mind...

1. Your island is a barrier island, breaking up the work triangle. You may find it awkward traversing between the fridge and the sink.

2. Do you have a more detailed diagram of the kitchen with measurements? Looking to see if your isles are wide enough all around the island.

3. For me, with all but one of the bedrooms upstairs, I'd prefer the laundry room to be located upstairs as well,, rather than slugging laundry up and down the stairs.

A Fox is pretty comprehensive here.

I'd add in that I hope you don't plan on having eat-in on the island - things will get cramped with chairs there. That breakfast nook is close enough to access at mealtimes.

I'd try to save money by cutting down on all the roofline additions and bump outs.

First floor bedroom could definitely stand a second window... I'm big on windows. It's not ideal to enter that bedroom via the bathroom, but that's better than going in through the family room, and I suspect it may be easier for houseguests to use that bathroom over the powder room, which requires a maze to approach.

Bedrooms 2, 3 & 4 could each have an extra window apiece, as this is currently designed. I'd also not want every bedroom on the second floor to have their own bath - people can certainly share! Design for hall entryway rather than jack and jill.

Of course, keep the master bath, but this could be slimmed down.

I am going to assume you have frequent overnight house guests/relatives, or that a room or two will be dedicated office space.

I'll repeat A Fox's comment about the double doors. One of the early iterations of a floor plan for the house I built did have double doors going to my study. Thankfully I ditched that notion!

Is a sitting room something you'd often use? What is the structure between the sitting room and the MBr?

I'd suggest having the laundry on the same floor as where most of the dirty clothing is generated.

Can you put a prep sink on the island? That might help with the distance between the fridge and sink.

In the house we had with my two kids and my ex, we had a large living room, large dining room, EIK, sun room, family room, playroom, and space for 2 offices downstairs. Guess what? We used the family room and the kitchen and the kids once they became teens used the sunroom. And once or twice a year we used the living room and dining room. We had a 3600 square foot house but mostly it was wasted space because of the way we lived.

Now for newish DH, myself, our dog, and an occasional guest, we built a 2870 square foot house but only have what could be considered 3/4 bedrooms. Every single room is used on a daily basis. What's the difference? We built what we need. The majority of our space is entertaining/living space in that our living/dining/kitchen is our largest space. We both use a "bedroom" as an office and the one guest bedroom doubles as an exercise room.

Are you building this house for how the 3 of you will actually live?

Do you have frequent guests that you need five bedrooms and 5.5 baths?

Will you use the family room, the living room, and the sun room?

Will you use both the breakfast room and the formal dining room?

You also mentioned you have a 15 year old son which says you're at the point where you're hopefully very healthy still, but if you're planning this to be a long term house, it might help to start thinking of the possible future when it might be harder to be lugging things like laundry downstairs. (Unless you have full time help and that changes the dynamics.)

If this is a long term house, have you considered an elevator just in case?

Understand, I have no problem with the actual large size of the house, but I wonder if you need the spaces as designated to live well or if your life is not needing 5 bedrooms/5.5 baths, you might be better off using the square footage to create a house that caters more to your lifestyle. Of course, only you can answer the question.

Once you do, I do see some issues with the layout.

I don't mind having rooms in my house that are not regularly used. I look at them the way I do an evening gown: may only be used every year of so, but when it is "required" one needs to have one.

I think that a LR with no fireplace will rarely be used. I think the location and entry to the sunporch means it will also be rarely used. Make both more inviting and better placed, and they will be used from time to time.

I like the length of the DR but not the width. It is way too narrow assuming one has a sideboard. It will be crowded on the sides. It needs to be at least 15' wide - even tier is better.

Well...since you asked...the plan looks like a builder's rather expensive house, presumably in a resonable neighborhood. It's big, fat and will have little natural light in the interior of the house (it's too deep and clearly not designed for natural lighting strategies).

For two adults and an adolescent son, it doesn't seem like a good, long-term fit. For example, will you have house cleaners every other week? Rooms, adjacencies, and circulation all seem excessive and not well thought out.

Is there something in particular which makes this plan appealing?

I'm sure you could do much better than this for what you are going to pay.

f you have regular large dinner parties, this is one of the first times in a while that I've actually seen a dining room that can fit 12 people comfortably

Thing is, the dining room is pretty far from the kitchen. Setting the table, bringing out the food, then returning everything to the kitchen is going to require LOTS of steps. If setting up for large dinner parties is a priority, the kitchen and dining room need to relate to one another strongly. Note that you'll have to carry plates to the far side of the kitchen /around the island to reach the sink /presumably the dishwasher.

Is that a beverage station or bar or butler's pantry between the kitchen and the dining room? That's a good idea, but is it enough?

Do you usually serve plates or set up a buffet? Consider where things would go /walk through it mentally. In my family we usually do pot luck /buffet type meals ... but I want a space for main dishes, a separate /away space for desserts, and a third area for drinks. Consider how you serve /walk through it mentally.

Off-topic a bit ... the kitchen seems to have been designed for style instead of function. It's large, but not necessarily efficient.

It's also nice to see a house that manages to get a window in each room.

Note that the full bath for the guest room doesn't have a window. If you were to bump the sun room forward a bit (you don't have a window on that side of the living room anyway), you might get some natural light into this bathroom.

While we're talking about this bathroom ... it's open to guests, so why go with the powder room near the garage entry? With this full bath available, I don't see anyone wanting to use that bitty nose-to-toes powder room ... and it's another toilet to clean each week.

On a larger sense, have you planned out the way that you might use each of your rooms?

Good question. This is a lot of space to build /clean /maintain ... definitely go through how you'll use each space and be sure you're not overdoing.

The master bedroom entrance. First know that those double doors may be a pain to use,

Yes, double doors are not a great option. They also require two hands to open and complicate placement of light switches.

Consider how far the master bath is from the bedroom area.

For me, with all but one of the bedrooms upstairs, I'd prefer the laundry room to be located upstairs as well,, rather than slugging laundry up and down the stairs.

Agree ... though I'd really lean towards moving the master downstairs rather than moving the laundry up.

I don't like that you'll have to walk through the kitchen /through the mudroom /through a door to reach the laundry. Laundry is enough of a chore without all these extra steps.

Also bump the laundry to the exterior wall so the dryer can vent directly to the outside. Cheaper and more fire-safe.

I'd try to save money by cutting down on all the roofline additions and bump outs.

Yes, all the jigs and jogs will be expensive, and they will push you towards a complicated roofline. Yes, these things are trendy right now, but SIMPLE is less expensive, more practical /functional.
3600
square foot house but mostly it was wasted space because of the way we
lived.

I have a 2400 square foot house and could say the same thing. My girls refer to the living room as "the Christmas tree room", and we rarely ever use the dining room (because of its distance from the kitchen).

I don't mind having rooms in my house that are not regularly used. I look at them the way I do an evening gown: may only be used every year of so, but when it is "required" one needs to have one.

Eh, I can't share this sentiment.

I like the length of the DR but not the width.

This long room with one big window on the end will end up feeling cave-like. Of all the rooms that would benefit from windows on two sides, this one is #1.

Other thoughts:

- Your only backyard access is through the breakfast room ... but once you place a table in this space, the door will not be easy to use.

- All rooms are nicer with windows on two sides ... with the addition of a few more windows, several of your rooms could have natural light from two sides.

- I'd bring the garage entry "up" so it's closer to the kitchen /across from the current closet. Why? Imagine you park on the side nearest the back of the house ... you have to walk the length of the garage before you reach the door, then you turn and walk the same distance to reach the kitchen.

- I'd open the door to the pantry from the mudroom ... which would place it closer to the garage entrance and would mean you don't have to walk through the kitchen to reach it.

Upstairs:

- The master bath is huge, but is mostly empty space.

- Do you really need this much closet space in the master? Consider, too, carrying laundry baskets upstairs, then threading through the master door /sitting room /hallway and finally the closet. Too many steps. On the other hand, the non-master bathrooms have minimal-minimal closets.

- With only yourselves + one child living upstairs, do you really want to clean four upstairs bathrooms every week?

- Imagine bringing furniture into Bedroom #2 ... will you be able to make that 90 degree turn?

- Note that (except for Bedroom #2), the non-master bathrooms are all minimal. Minimal isn't comfortable. These bathrooms have tiny vanities (I've lived with those vanities ... too small to set out a curling iron, no drawer storage ... never again). No space for storage of towels, extra toilet paper, or even a clothes hamper. I'd much rather have a shared bathroom that's big enough for comfort.

Overall thoughts: This house is designed to look fancy, not to live comfortably. Its circulation /flow and storage need attention.

"Library/Sunroom" is an oxymoron.

Unless you plan on running a bed & breakfast, or plan on your son moving his family in with you in the future, or something of the sort, the house looks too big. In your case, I think a local architect could save you a LOT of money.

ditto. That house is HUGE for just 3 people!! Higher taxes, main cost, cost to build, etc. EVERY bedroom has their own bath. That's insane to me. The upstairs #2 bedroom bath could serve all 3 other bedrooms upstairs and save ALLOT of money. Your budget must be unlimited. IMO....you're not gonna get younger, think about a ranch.