Thorfun

this really isn't an issue I'm just curious as to what people prefer as I'm sure it doesn't make a difference! both earths in the same connector or split across them?

but as @Iceverge said he'd tried insulating hot pipes and it didn't really help. so I still fail to see the point as the water in the HRC pipes still won't stay 'hot' for long, although obviously longer than without. I get that the cool water is recirculated back to the tank which could cool the water in the tank but in a 300l tank how much effect would the little in the pipes have on the large amount of water in the tank? I didn't bother insulating my HRC so I might've made a mistake but, tbh, I only ran the HRC as a 'just in case' scenario as most of my hot runs are relatively short so my dead cold leg might not be too bad. I will only find out once we're in and have lived with it for a while. and then if it is bad we can get the HRC working. if that means I have to run the ASHP a bit extra to top up the DHW cylinder then so be it.

I'm not an electrician and don't know for sure if they'd allow separate fuses and isolator. I bought a 3-phased fused isolator. not cheap and not small either! https://www.cef.co.uk/catalogue/products/4920299-100a-tp-n-metal-fused-switch we only have a single phase meter and running the house at the moment but I didn't want to have to upgrade later so just put the 3P fused isolator in from the start. when/if we move to a 3P meter it'll just be a case of connecting the tails to the fused isolator.

I've read 'insulate the recirculation pipes' a lot but no one has every said why? if the HRC is turned on by some automated means, e.g. when someone walks in to a bathroom, then surely the insulation is not needed as the pump will turn on and get hot water to the tap for when the person who entered the bathroom needs it. unless that person is spending 15 minutes doing their business surely the water will still be hot by the time they need it?

The lack of door requirements has come from the BCO from their technical department. So for our build it’s gospel and confirmed with the BCO and he’s going to put it in writing for me.

what do you mean by 'loft voids'? if you're insulating between and under the trusses why do you need to insulate anywhere else? here's what our loft looked like after insulating. we then fitted Intello Plus and service cavity battens in to the trusses. we don't plan to plasterboard the loft but the battens help hold the membrane in place.

I don't think they are inner rooms though? but as all first floor rooms have a secondary means of escape they're not considered inner rooms. that's my understanding

even if they are considered inner rooms they're allowed as they are a max 4.5m above ground level and are provided with an emergency escape window. see 2.11.e BCO said that we have one inner room in the basement that is an inner room and isn't permitted but that can be mitigated by fitting a smoke alarm in that room.

just to close this thread out..... I've heard back from the BCO and I am correct with my research. because we have a secondary exit from the basement and emergency windows/exits from the first floor we do not need protected stairways. as such we don't even need the doors between the hallway and kitchen. we might fit something in the future for sound reduction but nothing for now. it's one less thing to worry about.

I did quite a bit of research into basement u-value calculations as the surrounding earth means insulation levels don’t need to be as thick to get the same u-values. But it was so long ago I can’t remember the formula! the information was on here though in a post/thread of mine. You can try searching by author and if I manage to find it I’ll post it up for you.

i can try and take a photo of ours for you if you want? but won't be able to until Friday.

Afaik it’s the DHW tank. I would’ve thought your buffer tank wasn’t Mitsubishi? Ours is a generic 3rd party buffer tank so the temp should be the cylinder. Yes

might be worth a read as it's been asked before

(Expletive deleted) me @Pocster . This is starting to sound like progress!

I’m amazed you haven’t bought a Festool track saw. I have one and it’s ace.

welcome. we do these things for ourselves not for others so don't worry about what others think!

ahh...it's Windows only. if I can manage to find the time to get a Windows VM running on my Mac I'll download it and give it a go.

lol. Thanks. Can’t believe it’s as simple as that! Obviously it makes all the difference as to which I buy then! 😂

question out of curiosity really...... anyone know what the letters at the end of the Weidmuller terminal blocks naming convention mean? this one is PRV 8 BL 35X7.5 WS/RT https://catalog.weidmueller.com/procat/Product.jsp;jsessionid=F490E224509C0D79B55273816DE92EB4?productId=([1173910000])&page=Product whereas this one is PRV 8 BL 35X7.5 RT/WS https://catalog.weidmueller.com/procat/Product.jsp;jsessionid=F490E224509C0D79B55273816DE92EB4?productId=([1267840000])&page=Product what's the difference? why is the RT and WS swapped around and what does that mean?

thank you @ETC for the pointers to the building regs. I have read through what I believe to be the pertinent sections and cannot see why I would need fire rated doors between the hallway and kitchen. the regs clearly state that basements don't count as a storey when classifying a dwelling house so I see no need for internal doors to be fire rated. but I do need to comply with fire doors between the garage and the house. no problems there. The stairs leading from the basement to the hallway land at the hallway/kitchen threshold so this might be where the confusion lies as the stairway should be a protected stairway to comply. But in the section for Basements it says this: so ONE of those. I have an emergency external door providing escape from the basement which has a staircase up to ground level. Therefore I believe that the emergency external door makes our basement comply with the Building Regs if I'm reading the above correctly. therefore my stairway from basement to ground floor that lands by the kitchen doesn't need to be protected. I'll compose an email to the BCO tonight and then give him a call tomorrow/Tuesday to discuss. does anyone disagree with my findings?

This is the MOST helpful post! Thank you. Please can you link the BR document it’s from so I can go back to the BCO armed with this information. I especially want to read Appendix A which defines a basement.

I don't get this question. your VAT reclaim and the contractor's VAT reclaim have nothing to do with each other. Your contractor shouldn't be charging you VAT. if they are then there's nothing you can do to reclaim it. anything you've purchased can go in your VAT reclaim.

I was thinking about these 'fire door' discussions last night and I wonder if the confusion is coming from the terminology being used. in my mind a 'fire door' is an FD30/FD60 rated door with intumescent strips and auto-closers and a 'fire rated' door is a door that is FD30/FD60 rated. so, I believe that our internal doors need to be 'fire rated' and the doors between the garage and the house need to be 'fire doors'. at least that's my understanding. so our internal doors don't need the intumescent strips or auto-closures but do need to be FD30 doors. but I will double check with the BCO on Monday now that I have his number!

Found it quicker than I thought. 19.00 Internal Doors Supply and install new doors, frames and linings in positions as indicated on Architect’s drawings, to Employer/Architect’s approval. All new ironmongery to Employer’s approval

I don’t recall seeing anything on the drawings but there was a document with them that the architects created. I’ll have a look tomorrow and get back to you