I think scrapping the breakfast room for the WC and the utility room since it is IMO not a nice look to have those spaces at the front of the house . Then the logical progression of spaces is the LR and then DR then kitchen .I have no idea of the size of any of the spaces so if you want more details you need to provide sizes of all the spaces and in feet and inches and measurements not sq footage.

Thank you for commenting, as suggested I've updated the image with the measurements and positioning. The breakfast room is at the back of the house.

Maybe a w/c at the back right of reception 2, with door from the hallway, and stacked w/d upstairs, above the w/c, opening to the stair area.

Do bedrooms 2and 3 have closets? They must be very tight, especially with the chimney. I'd be tempted to combine them.

Your long term plan is blow the kitchen wall out to flush with garage.

Short term is get an architect to the site. : )

When you move in.

Set backs, site, permits......all of which you need to do anything. Then? start saving more money,

@Hanna Obano

Putting the WC near the kitchen is good regarding plumbing proximity. By utility room, are you thinking laundry? If so, I like the laundry near the kitchen, as the work is compatible. And your idea of utilizing the remaining space there as a study makes sense to me, because a study is a private space. I wouldn't want a public/guests space near the WC. 

Would your breakfast area become your formal dining room then? It has a nice window to what I assume is a garden. How do you feel about guests having to walk through the kitchen to get between the living and dining rooms? I think that may be the downside to this first stab at a plan.

Maybe Patricia is in to something. Maybe utilize the breakfast room for WC, utility room, and study. Maybe have the utility "room" be more of a closet so you don't waste space for the hallway. I'm thinking WC is just a toilet and sink? It could fit in snugly on the right side with a doorway between, access from the hallway. The utility room could be along your kitchen wall as a closet facing inward to the rest of that space, however you use it, even to continue to use it as a breakfast room. 

The biggest hurdle is installing the waste line for the toilet. Where I live, a 3" waste line is required. We recently did something like that, and access from the new  3" line to the main waste line had to go through a 2" line. The solution was something the contractor called a "grinder pump" which made a slurry that wouldn't clog the line. Adding a silent check valve made the whole thing completely quiet.

W/C is just a toilet and sink yes. I like the idea of the w/c in the back right of the reception room near the kitchen where we hopefully can utilise the existing plumbing, though a grinder there shouldne be too disruptive for the people in the front reception room. The utility room would be a laundry space with the washing machine, dryer and a sink.

I don't think we actually need a formal dining space, we have a dining room right now in a house of a similar layout and it's become a study/dumping space only really used at Christmas for a few days. The breakfast area is where we'd eat, I don't think guests would mind walking through the kitchen, it might even be nice.

Bedrooms 2/3 don't have closets but are a pretty ok size for kids, we will probably get rid of the fireplaces down the line for additional space.

Use the breakfast room as a family room. TV, hang out, games. Reception 2 becomes the dining room. Reception 1 is the main living room and the sun room can just be a sun room. Agree with above, perhaps put the laundry in the garage. If you need an office, tuck it into a corner of the formal living room.

You are in the UK, correct? Is your garage a tandem garage? It seems exceptionally long. I, too, agree with the idea of utilizing the garden end for your utilities AND a “mud room” with powder room. You could create a pass through between the garage and Reception Room 2, with a door from the entry through the space to your back garden (I assume the long entry is your only access to the garden??). The door into your house would be right near the window in that reception room. Just a thought….

Hi all, we are in the UK.

The end of the garage is currently a kitchenette and will eventually be my husband's 'test kitchen' but it can certainly be sectioned off to include a mini laundry/utility/boot room. We really don't need a dedicated dining room in the reception room but it could be a study/office and a partitioned w/c as we both work from home.

Your ideas have been very helpful!

You need an architect so you dont remuddlethe house. Right now most of the suggestions, especially Patricias sound like a remuddle

We plan on hiring an architect, but I think it would be good to engage them with some kind of vision for the layout to start. I think we would be happy to knock walls down and reimagine spaces...within reason

Is that space between the “L” part of the house between the garage and the breakfast/ sun room a garden? I see doors in the garden room facing towards the very top of the lot but it’s unclear what’s in that “in-between” space. It seems like the breakfast, kitchen, reception 2 and sunroom are set up to be the “heart” of the house with outdoor access. Do you use the front reception room as a living space? I wonder if that would be a better study and make it smaller by putting the powder room in between the two reception rooms opening into the hallway.

We plan on hiring an architect, but I think it would be good to engage them with some kind of vision for the layout to start. I think we would be happy to knock walls down and reimagine spaces...within reason

All you need to do with a talented architect is give them your needs and wants. Then let them figure out how best to utilize the space without remuddling the house. That's what they're trained to do. :)

Do you have pictures of the interior spaces you want to change?