I think this space is plenty big enough for what you want. The velux suggests that there is limited head height in part so perhaps the bath should go under the velux

I'd go for more storage and a separate Utility. If you remove the Chimney stack in the dining room and cut the room in half you can make a good sized Utility. ( You probably have another fireplace in the formal lounge ) Doing this, probably takes the allocated kitchen size from a 1/3 to a half and you get a utility too, so way more storage. Inside the entrance on the right of the kitchen, full height units for storage including coats and shoes, as there's no room in the hall.

I agree with above - you're going to have a lovely bright utility! The usual way people extend is to put the utility and WC into the darkest bit (turning the utility 90 degrees like suggested above) which then pushes the kitchen/dining/living towards the garden end. But that would have involved more walls coming down - I feel like this is a case of you got what you asked for, but now you're asking for something else. I think the architect has come up with the best layout though for minimal work involved - putting the dining table in the dark space will just make it a corridor and you'll mostly eat at the island in the light room with garden views (other than dark evenings like you say when being in dark dining room will be quite cosy). I know people who have done that and regretted it and wished they'd put the kitchen in the dark bit as you tend to be doing something in there anyway and you'll be looking through the lovely bright space rather than being in it. Getting a decent second living space seems important to you so the current layout achieves that. You could perhaps add some high level transom windows between kitchen and utility to bring more light into kitchen (depending on where tall/wall kitchen cabinets are going to be and how ceiling is). Another option that you haven't mentioned is to put the new lounge into the dark space (then you'd have to call it a snug!). Leaving the new space as kitchen and dining. But perhaps you want the sofas to be looking onto garden, or you don't want it right next to the other sitting room - which is understandable. So it depends on what you'd use that living space for - or would also having a couple of upholstered chairs or a window seat in the extension allow you the flexibility you are looking for? Regarding the loo situation - I don't like having to walk through the utility to get to it (mainly as you're going to have to clean/tidy your utility every time guests come round, no thanks) - alternative is to walk through the WC to get to utility - would result in a bigger WC (you don't want to squeeze between toilet and basin so put them on the same wall) and a more useful utility space - and you'll have one window into WC and one into utility and nobody will be walking through the cat litter tray - could keep the pocket door idea so that it's more like one room normally, but easy to close off the messy utility when guests arrive (if that is ever allowed to happen again!)

We are in the process of extending (a joint project with our neighbours to gain an extension to the front box room, then along the ground floor across the front and down the side of the house). We're having some last-minute layout dilemmas, the floor space isn't the biggest, but we will gain some essentials from it (bigger kitchen, downstairs shower/toilet, office space, porch and the bigger box room upstairs). Our shower room is going to be fairly slim (worked out as 900x2900mm at the minute). This also creates a slim corridor space beside that leading to an office which I've bumped along a bit to give some more space (sacrificing utility space at the other end, when you compare my Ikea layout with original drawings). The other option is to access the office from the lounge, meaning we could lose the corridor altogether and widen the shower room, but that would make the office open to noise from the lounge and I think it's a weird place to add a door. We're also struggling with options for the laundry/utility space too and whether to just include it as an extension to the kitchen. I've added some screenshots and links to an Ikea planner I used to map the ground floor out completely (ignore the colour and the basic mapping of furniture etc. it also doesn't include the pitched roof and Velux windows). Any input would be appreciated, I'm just looking for layout ideas and tips for anyone that has similar sizing/spacing set-ups. Thanks. Links to 3D plans: Ikea plan 1 with laundry space included in kitchen - https://kitchen.planner.ikea.com/planner/#/gb/en/planner?projectId=192B977E-9364-4348-9DF7-A3D64BC3767A&ref=share Ikea plan 2 with wall separating laundry space - https://kitchen.planner.ikea.com/planner/#/gb/en/planner?projectId=192B977E-9364-4348-9DF7-A3D64BC3767A&ref=share Screenshot of Ikea layout plan 1... Architect drawings... Internal before: Internal after: External before: External after: