Spinny

Danny, I would say the PWA applies anyway, because they are building at the boundary. I would just assert that to them in the letter and tell them they need to comply The PWA is potentially your friend here, it is the law, and it makes your agreement with the neighbour legally binding. I certainly would not tell them or suggest to them that you want foundation drawings to determine if the PWA applies. As far as you are concerned they are building at the boundary and so the PWA does apply. I would say, ask for the construction drawings for the extension they are building. This is important because what is built may be or end up different from what is only approximately depicted in planning drawings. Do you not care what type of bricks or blocks that wall is built in ? Do you not care if the eaves illegally overhang your property ? Do you not care when conveyencers start to ask you whether the building at the boundary was covered by a PWA when you try to sell your house ? Do you not care if the drainpipe discharges onto your patio ? Do you not care if their kitchen extractor belches out over your patio ? Foundation depth is not the determining issue here. Foundations typically extend beyond the wall itself - which would put them on your land ! A construction drawing would show this, eaves width, height, rainwater handling, will there be a soakaway ? The legal responsibility is theirs - you need to state that unequivocally and invoke the act. They need to do the work and make the running here in order to get your formal written agreement, otherwise they are in breach of the law. I would not begin to state to what you will agree with at this stage. Things need to follow the PWA process - you can't just make it up yourselves. It feels like you are wanting to be super friendly and helpful to someone that appears ignorant of the law, too rude and selfish not to have spoken to you way before now, is breaking the law, and could make your life a misery for 12months and more. Be positive and assertive, hold them to the law, do not make concessions before you have even got them on the right page legally. There is a negotiation and agreement process here which is legally required. As an example the boundary line is not necessarily defined by your fence. Whose boundary is it in the deeds ? part of the negotiation might be you deciding that when the wall goes up (very likely to require complete removal of the existing fence) that you would decide not to have the fence re-instated giving you 4 extra inches of useable garden. Don't start rushing to complete a process in days that is supposed to take weeks or months.

Are you having a silt trap ?

Any reputable experienced builder would know about the existence of the PWA and would not build illegally without ther being compliance and signed agreements. Don't let the neighbour hide behind the builder - all the responsibilities are the neighbours, he is responsible for everything the builder may do or say as his contractor. Take photographs now, during, and after. Any disputes need evidence. Builder is required to have liability insurance - ask for evidence of it. Make sure projections are defined on drawings in the PWA before work begins. Our neighbour was going to build at the boundary, until I sent him a formal letter giving notice that any projection over my land was against the law. He was supposedly going to use an infinitely thin undefined capping on the drawing ! Then he agreed to set back 50mm, then at marking out insisted on 40mm as capping would project 32mm - FFS.

Oh, one other thought...

Certainly looks like the PWA applies. https://www.gov.uk/government/publications/preventing-and-resolving-disputes-in-relation-to-party-walls/the-party-wall-etc-act-1996-explanatory-booklet#part-1-party-wall-etc-act-1996 I suspect legal advice line etc advice you will get is to send a registered delivery/signed for letter to your neighbour. Inform them in the letter that the Party Wall Act applies to their building plans and work, and that they are required by law to adhere to the requirements of the Act and that you are hereby giving them formal notice that they must comply with the Act before work commences. I have had direct experience of similar with a single storey extension built by my neighbour. Formal letters and documents are required. Assuming goodwill and that everything goes without issue is a dangerous thing. Sadly there are too many people out there that through ignorance, stupidity, selfishness, dishonesty and malice will cause problems. Prepare for the worst and hope for the best. After all any sensible neighbour would have knocked on your door to set up a chat and a coffee to talk over the plans and any concerns, and would already be fully aware that under the PWA they need to issue notices in the correct way, obtain your agreement, and give notice. A Party Wall Agreement or Award normally covers off many of the things that could go wrong...damage to your property, access period to your property, working hours, noise and dust, reinstatement of things taken down (e.g. fence), vents, outlets, and pipes etc not discharging onto your property, not having diggers driving over your property, size and materials of what is to be built, access security for the site. Also check whether they have a building notice with the LA, talk to the LA planning service, ask who is doing the Building Control for the work. Look at the plans very carefully and closely - we raised queries about inaccurate drawings regarding ground levels - got no answers to reasonable questions. Turned out the neighbour was going to raise up the land on their side of the boundary not declared anywhere.

I'd have thought the Party Wall Act is likely to apply. Building anything projecting over your land is trespass and legal action can be taken. When you say the extension is 'right on your boundary' do you mean the wall will be built against the boundary, or is the wall set back from the boundary by some distance ? You are not allowed to build eaves and guttering that project over somebody else's property. How close is the extension to your own building and foundations ? Have you examined the plans which have been given approval ? If you have house insurance then you could call their legal helpline for advice. You can also get some initial free advice from the Faculty of Party Wall Surveyors https://fpws.org.uk/services/ has the telephone number. Clearly the neighbour is a ****. Act accordingly. This may seem like a request for scaffolding, but many other things can occur if you don't push back against somebody that has no regard for others.

When you say 'old boy surveying engineer' do you mean a qualified professional structural engineer with professional insurance providing a paid for written SE report to you as customer ? Why exactly do you believe something has to be done with the steels ? Do you have any movement or cracking anywhere around the house and garage ? Is it just your personal concern over the appearance of rust and concern to do the right thing for the next 50 plus years ? Rust on steels is common. We had a much smaller pair of steels exposed during our extension work that had been in place since the 1980's and had plenty of rust (see photo). I asked our structural engineer whether they should be replaced or anything. He came and poked them hard with a screw driver looking for anything more than surface type rusting then said they were good for at least another 50 years. So I wire brushed as much rust off as possible by hand and using drill attachment, then used Neutrarust 661 liberally, then 2-3 coats of an iron oxide paint. See Pics. Not saying your situation is the same, but before embarking on costly structural works - presumably to make sure the house is fit for the next 50 plus years - you really want to base it on proper written professional advice. I am sure your house insurer would expect the same. (PS I am not a builder, engineer, etc, just joe public)

Thanks Nick that makes sense, (Though I still prefer to avoid the rubber bungs just because I have had mutiple blockages and back ups. I'd guess likely 95% of people never ever have a blocked drain or backup in their lives. And it is not just me, but also my neighbour that can/has blocked my drain, and I am downhill from him.) With the plumbers I have had it always seems to be impossible to have a conversation and get a shared agreement - before you know it they have gone off and done something and just missed out the planning stage altogether, and then you look at it thinking oh dear, why have you just put loads of elbows in and strangled my water flow or whatever.

Thanks again. TBH I don't really fancy those bung type connectors. Our drains have been blocked a few times creating some backup. Most recently by our neighbour, whose drain feeds into our manhole - and he has two extensions and no soakaway. So if the drains backed up I wouldn't want a leak at or under floor level. Seems better to me to have a leak at a manhole cover or surface drain at ground level outside. To effectively ensure any back up would rise up the waste pipe rather than leak out. A plumber fitted a bung but it seemed loose and potentially prone to leaking. Also might an enterprising stray rat disturb it. I have now seen there seem to be some small pipe angles - could I somehow put a 15 degree or 11 degree bend on the 110 pipe to try and get it vertical ? Also can I ask what the form is for drains and wastes in kitchen cupboards. It seems to be common to keep the 110 drain under the base board of the cupboard and convert to smaller waste pipe size below the baseboard and just bring 40mm through the base board. But am wondering whether this is ideal because... 1. If there is a leak at the 110 to 40 join (including by a backup) then you won't know because it is hidden. 2. If you want to clear the 110 pipe of a blockage, you can't access it to rod it except through the 40mm waste pipe, or from the other direction. 3. If you want to take the waste pipe and traps apart to clean them all out, then you can't remove the lower 40mm waste pipe because the join to 110 is below the baseboard. Your trap door partly addresses this although seems to be rather fixed in place by water pipes also going through it. Is it just nuts to bring the top edge of the 110 pipe through the baseboard ? I am possibly over thinking I guess. Poor trades people make you paranoid. Pic show what is currently in place in my utility - will place two 40mm connections through the base board - is this madder than a mad thing - should I get it reworked before the kitchen fitters come ?

See photo. The drain pipe running to our kitchen island sink unit does not come vertically up from the floor. It runs at a jaunty angle both front/rear and side/side relative to the kitchen sink cupboard that will sit above it. So how is this best dealt with so that the waste pipe/traps etc inside the cupboard can be kept neat and vertical ? (PS Any photos showing how drains are normally brought up into a kitchen cupboard ?)

Thanks. It is a rainwater downpipe, but it is feeding into the foul drain/sewer and not into a soakaway. It only drains a small portion of the extension roof and one of the downpipes for the original house roof drains down onto it. So was acceptable to BC - almost all of the extension roof water will go to a rear soakaway. It is also the only surface drain in that area, so would like to retain that.

Coming back to this one now. Have cleared out some hard core to show the drain pipes that are there - looks like two 45 degree bends connected together. What pieces can I use to move this drain about 6 inches to the left ? (without moving the wavin chamber) (PS might there be any way to connect a small shallow drain/waste pipe into this gully to carry discharge from a water softener inside an adjacent wall about 1m away ? For example by attaching a 40mm pipe into the side bush somehow ?)

OK thanks for comments. The supply pipework is 32mm MDPE mains in, connected into 22mm copper (16mm MLCP tee to kitchen, 15mm copper tee to outside tap) through water softener (currently on bypass), then approx 5m of 25mm MLCP pipe to the cylinder location, final 1m in 22mm copper to the reducing combination valve. I was getting 37 l/m from the outside tap, so I know the mains supply is capable of providing a continuous 37l/m through 15mm copper. So the main supply through the 22mm copper and 25mm MLCP should be providing at least that and one would think 40l/m + into the combination valve. Mains pressure 3.5 bar. Unfortunately I can't change the 5m of 25mm MLCP with its press fit connector at each end, because it runs under the suspended floor which now has underfloor heating installed. Had I seen the MLCP connector bore reduction at the time I would have insisted the plumber put in 32mm MLCP. But that is the big unspeakable secret with MLCP and press fittings. I have seen some Wavin Tigris M5 / K5 press fit MLCP connectors which claim ''The new Wavin Tigris K5/M5 with Opti Flow reduces the pressure loss in the installation due to the up to 50% larger orifice..''. Mentioned them to my plumber who promptly claimed they would make no difference, and proceeded to fit cheaper ones he uses. A lot of trade are not interested in using anything except what is available off the shelf at their chosen merchant. System performance for the customer doesn't come into it - in fact I have never seen a plumber measure a flow rate.

I am talking total combined output there - that is Hot Flow + Cold Flow. If it is Christmas and I have family staying - say every year for the next 15 years. Then you have 6 adults in the house, maybe 2 or 3 grandchildren. You want to run 2 showers at the same time. Someone is running taps in the kitchen making breakfast, someone just put the washer on, and someone flushes the loo. So if the system can't handle it, someone is getting a bad shower, and you are into shouting round the house about who can use a bathroom or ensuite. At present the highest simultaneous output I am getting is 34 l/m combined hot and cold downstairs - that is 17 l/m each for hot and cold. Hot flow and cold flow are not separate, they all come through one input pipe and combination valve. I am only getting more like 20-24 l/m simultaneous combined on other outlets. I don't think this is unusual, part of the selling point of UVC vs gravity fed is the ability to run two bathrooms etc. My mains supply should be capable of 40 l/m+. Are we really saying there is no-one here that has ever seen flow problems with a domestic system regardless of how it is plumbed.

I mentioned on another topic, plumber is planning to replace my Caleffi pressure reducing combination valve with a 28mm valve to improve flow (my pipework is 22mm). I am reading some stuff about pressure reducing valves having to be sized correctly for expected flows, and sometimes 2 valves plumbed in parallel may be required - one for low flow, one for higher flow. (I guess I expect flows from say 5/6 l/m with one tap on through to say 35-40 l/m - 2 showers, couple of taps, kitchen appliance all going.) (Seems unfortunate that someone can't design a pressure reducing valve that works well without restricting flow over a wide flow range) PS Do you actually need to have a balanced cold ? What experience and advice can people offer re combination valves for domestic UVC systems and maximising flow ?