hi there. looks like you have all the advice you need here. as we have done this several times, the final outcome really depends on what you and your neighbour decides. you can either do the above - erect a new wall and this becomes the new party wall. this is the ideal scenario as it means you can maximise the space within your new extension and also if the neighbour is planning to have an extension then he/she will use the same wall and contribute the cost of building the wall as and when they decide to do so. the other option, and this has happened is that the neighbour says that they do not want you to build a new wall and it must be left as it is. then yo have to build your wall inside the boundary existing wall. this of course takes up more space within the inside of your extension. you can handle this matter in two ways - either a friendly chat with your neighbour with the drawings and proposed favoured scheme. you would need a letter of agreement between the neighbour in question saying you would agree to cover any damages that could occur during the build caused by the extension and take a schedule of conditions (pictures of the neighbouring property inside - where the extension will be built). this is both you and your neighbour know the existing condition of the property before the build. the advantages is that this process takes less time but is less formal if you want to cover your backs completely and have the matter handled independently, then the best thing is to handle the matter with party wall surveyors (either you will just need one, or two depending on your neighbour). this would be a good idea perhaps especially if your neighbour is planning an extension. however the process can last up to 6 weeks easily, so if you are in a hurry to proceed this might not be the case. hope this helps and message us if you need more information.

Ok, so I've never commented on Houzz before (despite being a huge reader) but the shape of your house really intrigued me as it's very charming but quite tricky. Looking at just the ground floor, I think that an extension that fills in the 'rectangle' floorpan of the whole house might work. The loo and shower should be moved so that they are not blocking off movement flowing through the ground floor. To get a bigger hallway you could move back the wall currently going into the kitchen, so that you incorporate the small window into the hall. Remove the wall by the stairs and turn the stairway itself into a feature which would make the hallway - and stairs themselves - feel much roomier (I can't see from your floorpan whether they are already open to the hallway). What's currently the kitchen could become a utility with downstairs loo (move the shower upstairs into new bathroom over new extension, taking a bit from bedroom 1?). I have recently had an extension kitchen built on our own house and turned the old (tiny) kitchen into a laundry/boot room - best decision ever with a growing family! In the utility room you could put in a stacked wash/tumbler (if you want a tumbler, or else just cupboards/laundry on top) and a downstairs loo, as well as more storage. In the new kitchen, you could have double/french/sliding/bifold doors as per your taste looking out SE into the garden, creating a long sightline - and feeling of space - from the garden right through the kitchen into the far room. This would create a spacious-feeling kitchen tied into the rest of the house. You could block up the door into the current dining room and take out the wall between the dining/living. Keeping the dining room as dining, this gives you a cosy room there for small intimate dinners but also the potential to have big dinner parties on a long extended table stretching out into the living room. When not entertaining, that slightly self-contained room (as it's not a through-route as is the rest of the house) could be used as a study/quieter reading room. You now have a house that is welcoming for entertaining - guests come through the front door, where there's space for coats/hatstands, straight through the open door into the living room and are greeted by the fireplace ahead of them, and look round to see the dining table. Downstairs loo for guests nicely separated from all the action. Please excuse my very rough sketch of what I mean, and its lack of scale!

I'd agree with both angm47 & man about the house. Before we bought our current property, we were set on buying a house & had people in to give us quotes on work, etc but then discovered the property had mundic & we had to pull out. Fortunately, we hadn't spent anything. Where we are now, we had plans to extend but once we'd lived in it, our ideas changed. Although we've still extended, it's completely different to what we'd initially thought we'd do.

Hello and thanks for your prompt reply. The drawings provided show that the support beams are 203mm depth and therefore they will be too big to sit inside the ceiling void. As the weight per linear m is 23Kg as detailed on the drawings it may be worth asking the engineer to reduce the depth and and increase the weight so the beam can be inserted into the ceiling void. I note that there is also a couple of posts in the stud wall and these could be upgraded if necessary. I do not make these suggestions lightly. The main benefit of inserting the beam inside the ceiling is the removal of the shadow cast on the ceiling. The return nibs on either end could be cut back and if needed posts could be fixed direct to the brickwork to provide vertical support. There may need to be a spreader plate welded to the bottom of the post in order to mitigate the point load on the foundation. Obviously this is more of a structural design issue. Is there a good reason for not centring the bifold doors to the external wall? You have so much height on the flat roof why not put a warm deck roof on instead of a cold deck with in cross ventilation? Can I also suggest a warm pitched roof too. You may find Web Dynamics TLX Goldto be a very useful form of insulation as you will only need about 75mm of PIR insulation in between the rafters. I've never been fortunate enough to meet a building control officer willing to accept a heavy duty Catnic lintel over a 4M bifold door. I thought the under stairs might be the position of the meters. I would consider relocating these to an outside wall. Then turn the WC through 90 degrees and design it under the stairs. If I was planning a kitchen diner extension with a beautiful bi-fold door looking out into the rear garden would try and create a direct flow from front of house to the back. I would move the utility room into the middle of the house to provide a direct line of sight from the front door to the rear garden. GD3 would provide access into the utility room. I'd consider moving the door along the living room wall so it could open into the hallway. This would allow a 950mm wide fully glazed door to be placed between the hallway and the kitchen diner. With regard to the position of the new extension wall which is adjacent to your adjoining neighbour I suggest that you look up the party wall act 1996 booklet online here - https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/523010/Party_Wall_etc__Act_1996_-_Explanatory_Booklet.pdf The part that is of interest is "Line of junction - building astride the boundary". If you build across the boundary you should gain at least 150mm of additional internal floor space along the length of the outside wall. Also if in the future your neighbour decides to build an extension they can utilise your wall for if they pay half of the cost of its construction. I'm sure you know that you are responsible for paying all of the costs from all sides relating to the party wall agreement. If the neighbour on the other side is within 3/6m then you will need an agreement with them as well. The architects drawing indicates that the drain is not adopted or shared and therefore you will not require a build over agreement with the water authority. Best wishes Andrew