Hi, If i may I would like to ask about the extension first: Why are you not building over the boundary with your neighbour. This would allow you to build the extension in line with the existing party wall. As you are building within 3M of the neighbours property you still need a party wall agreement. Judging by the single roof light can I assume the roof is pitched from existing rear wall to new rear extension wall. If the side wall moved over then it would help to make the shape of the room more uniformed. The return nib could also be removed with the inclusion of a post of approx size 90mm x 90mm. Will the extension roof be vaulted or will the existing ceiling run through into the extension? Will the new support beams be inserted into the ceiling void or will they sit down under the ceiling? It looks to me as though the brushes steel cooker hood does not suit either of the kitchen styles. The separation of the hood also breaks up the flow of the wall units which I find a bit distracting. The island seating seems to be facing the wrong direction especially as you have removed the posts now. If I was designing the kitchen I would want the space to work for me. Currently there seems to be a lot of circulation space which could be better managed with a smarter kitchen layout. I would look at the island and write down what I want it to bring to the kitchen. Is is a focal point, where will my guests be looking from the stools, will I be cooking or prepping food on the island, how does the kitchen triangle rule work with this layout. It may be worth considering removing all of the kitchen units on the wall adjacent to the lounge and moving the island up by 600mm. Then I would looking at the position of the kitchen units on the other wall and consider only having only wall and floor units to stylise the design. The american fridge would need to be found a space. Not much help but something to chew on.

Thanks for your input. I agree re the kitchen layout in the first option but we are just struggling with that wall! Would you build essentially all the way up to the boundary? Or would you leave a slim gap to be able to clear weeds between boundary and diagonal wall? The roof is unfortunately a bit complicated as there is a shared roof over our existing dining room and the neighbours dining room - the plan was to tie in this existing roof to a new crown roof on our side so we don't impact the neighbours. If we went for a diagonal wall and therefore a non 90 degree corner we would probably swap to a flat roof instead of crown to keep costs lower.

That is a really good space! A couple of interior design tips and tricks would help for planning the layout. One would be zoning, as it is 8mx5m it is big so think about what sort of tasks you might like to have space for, 1 would be dining and like you mentioned you could have some lovely accent chairs facing out into the garden. The second would be scale, don't afraid to go big on the dining table, 8 seats would fit comfortably as well as a couple of large comfy chairs as well. You can also anchor the space by using some kind of area rug. Good luck and Congrats again on your new home!

I think those yellow walls should be 1.2m and maybe even longer as you don't have a lot of wall space to work with. Personally I am not keen on peninsulas as I think they trap the kitchen user and divide the room in two. I far prefer islands. Of the two suggested layouts I prefer the top one but careful measuring will be needed. Pushing the table up against the island is practical but still I am not convinced that you have the space to seat 8 people. I have 6 chairs and my table is already 2.5m long. 8 chairs will not be comfortable in that space. Do you need to seat 8 people all the time? Do the proposed layouts show a window where you have a door on the left?