Good afternoon Anna. Interesting. Here's the dilemma ( Houzz pun? ) ..the 15.19 if accurate does not scale with the pic as shown. Judging the sink wall to be about 5 ' (4' 6" perhaps)long, ( 2' for counters, 3' working space) ,it leaves less than 8 ' between the small wall and the front window wall. The pic shows a wall about 12' long. ( Notice the living room area is almost square).

It really depends on what you want to achieve with your loft conversion. I've shown the stairs where I'm assuming they would work best to give you a masterbedroom suite - so with a walkthrough wardrobe and ensuite, to the back with a dormer extension, and potentially another room to the front with some rooflights. I don't really have enough information to be able to give you any definitive answers on that. This would be based on my assumptions of that kind of house, and the sort of things that most of my clients would ask for. Your house might be different and your needs and desires are unique to you, so are quite likely to vary from my assumptions. I think it's unlikely that you could do that loft conversion and the ground floor and other alterations within your £40k budget though. So that's why I would do it in stages and focus on the ground floor to begin with, because that seems to be the main area that doesn't work. I expect that increasing bedrooms will increase the value of your house a lot in London, so it might well be of interest to you from that perspective, but it might not really have that big of an impact on your life in your home for the short term. It depends on your priorities and what your long term plans are. Personally, if this was my home, then I would spend all of my £40k on the ground floor, use furniture to divide up the front bedroom for the kids, and even install a shower-room to the ground floor where I'm suggesting a loo/utility, and put the washing machine in the kitchen. Then I would get a really good sofa-bed and turn the lounge into a very flexible space that can be quickly and easily turned into a comfortable guest room, then let it on airbnb with guests using the downstairs shower room. That way I would quickly save up the money needed to do the loft conversion so I could have all the works done over a few years. That would be my approach, but airbnb is not for everyone and you may not need to do that to get together the extra money needed to do the loft in a few years time. it depends on your personal financial situation. There is a lot that depends on what you personally need and want, what your priorities are, and what your personal financial situation is. Quite rightly you've not shared all of that on here, and i wouldn't expect you to because a lot of that is private information. I hope this helps within the limitations of what I can suggest based on the information I have!

your house is almost exactly the same as my own house that I am currently doing work on. I would turn bedroom 3 into an en suite and a main bathroom - in your house you would have windows in the both rooms - I've attached my property floor plan to give you the idea. I too have a sun room attached to the back of my property which I was turning into a sitting room and putting a home office to the front of the property by partitioning the front room. I would definitely go for a utility room, they are a valuable luxury if you have the space, washing machine, mops, vacuum cleaners, coats - it's great to have somewhere to store all these things...

Shauni's suggesged plan is good and allows a view out if you glaze or part glaze each door. I would consider adding a surface mounted sliding door to the loo to make it easier to navigate the space and let more light in. Could the washer and dryer not go upstairs in the cupboards next to your bathroom? Or has this bit changed? Would give you space for a boot room next to the garden which would be a good use of this space.