Barny

I have an airtight test booked for Monday. I need to block up the MVHR vent / sink drain for the test. Can anyone recommend a suitable tape/cover? Obviously not using Siga which I used for airtightness as I won’t get it off after the test. Thanks

Hi This feels like a stupid question. We have block and beam floor with sleeper walls standing up. Just putting the airtight membrane in before putting extra insulation on top. I am assuming I need to cover the sleeper walls in membrane and tape to the membrane on the floor? This detail is not on my drawings from architect. is this how others have done it? Like a really complicated Christmas present!!

Hi All Can I check what you did for a fire control plan (and construction phase plan), which MBC require? My builder has never heard of a fire control plan let along drafted one. I was going to use the draft MBC gave me but wondered if every thing in their was a requirement ie unlock mobile phone on site, fire drills every six months etc? I would appreciate hearing what others have done. thanks

Hi can anyone recommend ducting insulation and airtight tape brands / suppliers for a passivhaus? Ideally, cost effective ones? Our architect has given brand names but I can’t find them for sale in this country. I think the world of insulation and tapes and moved on (EPS definitely has) but my architect is still using his little book for 5 years ago. thanks

Thanks - very neat!

Thanks Ian. Is that an insulated 100mm duct? Thanks

Hi we are aiming for passivhaus certification and have 3 phase electric. Has anyone done this? What size ducting did I you use for the electric penetration through your foundations? we have 150mm ducting for the cable to TBS but that seems large Togo through foundation. I know we need the insulation and airtight tape around the cable but still seems like 150mm is large. many thanks

Thanks - I couldn’t find any regs either!

So the stop tap doesn’t need to be a minimum height off the floor? Is 12” enough clearance? thanks

Hi. My architect positioned the water and electric coming into the plant room under the MVHR unit, which my groundsman has done as per the plan. Does anyone know how high a stop top needs to be or how much space do we need to leave below the MVHR unit? I don’t have a plumber on site yet to ask this and MVHR needs to know / tell MBC so they can agree the joists. i am assuming the electrician just go around the edge of the room so it an issue? many thanks

Hi can anyone recommend a tin smith near Peterborough to do standing seam aluminium roof and cladding? thanks

Hi. Does anyone know of water board approved ducting for water pipes where you can’t get to the required depth? I have found some products on line but not sure which are sufficient. we can only go circa 450mm deep as we are crossing a culvert. Thanks

We had horizontal GSHP at our old house (so can’t comment on the bore hole) but I would say that when GSHP goes wrong it is expensive. We had a leak and it was ££££ to drain, fix and replace (installer picked up the cost for that). A few years later the connection was leaking - thankfully a bit of sealant solved that so we didn’t have to drain it again. Then the pump itself - was fine for 12 years except the control panel stopped working and it was £1500 to replace and a small electric component needed replace and again expensive. it is supposed to be more efficient than ASHP, which I can believe but it isn’t as responsive so I think you end up paying more because you have it on when you don’t need it. The servicing costs are very high as there are so few of them around so you struggle to find anyone. when we sold our house, people found it confusing and distrusted it would work! we are putting ASHP in the new build!

Has anyone used efloor by floorspan? it looks similar to Tetris - does anyone know how they compare? the price i have for the Tetris is expensive so looking for a cheaper EPS. Has anyone else looked into comparisons? thanks

I think there will be thermal bridging issues between the block and frame. Has anyone got a design that works around this?

Hi. Has anyone done a passivhaus (aiming for) timberframe using block and beam foundations but not using Tetris? Our foundation design currently uses Tetris to keep the thermal bridging down but it is coming out 50% more than a raft (which we can’t have due to site conditions) and 100% more than traditional block and beam with 200mm of PIR. Just wondering if anyone else has achieved near passivhaus using block and beam and can share foundation designs? thanks

Thanks. So foundations, over site, masonry, sleeper wall, ground floor make up and thresholds is quite comparable with a raft foundation. does anyone know how much it costs to prep the ground for a raft? I am just blown away that block and beam seems to be a lot more expensive than raft (which is supposed to be expensive).

Hi i I have just had my first quote through and fell of my chair. They are quoting £87k for 198m substructure (ie £440 per m). This includes foundations, over site, masonry, sleeper wall, ground floor make up and thresholds. The house is timber frame on block and beam so I am a little confused by the above breakdown. I get the foundation - ie strips of concrete. Thresholds we had drawings from architect so again get that. what is the over site and sleep wall? We don’t have these on our foundation drawings. would the ground floor make up be the block and beam with insulation, damp proofing etc? Our heating guy was going to do the screed so wonder if this is being double counted? can anyone give me an idea of price per meter you would expect for substructure (exc drains)? MBC quoted for doing a raft foundation and it was cheaper than this which I was not expecting - not least because my architect said to do block and beam because it is cheaper. finally, they have also quoted another £20k for a telehandler - in addition to above. Is that reasonable - honestly I couldn’t believe this. I have just had the demolition done for £8k and they had telehandler, diggers and other machines there for 2 weeks so I assume this is a mistake or they are taking the mick. we have been struggling for a few months to find anyone to quote and these guys have come in £200k over what I was expecting.

Hi. we have planning permission to install a separate access which crosses a ditch. It is just a field access so not worried about fire engines or anything like that. the drainage board have given permission for us to install a culvert and have the access over the top. It is just a 5m stretch of M1 concrete pipe back filled with soil and concrete filled hessan bags on the sides to give a neat edge. We need to have a hard standing for the first 5m from the road - all good! but the council are insisting I submit a structural assessment of the culvert design as a pre planning condition. has anyone had to do one of these and any idea what is needed? I have the technical sheet for M1 concrete pipes - is that sufficient? we had 22 planning conditions for the house where the council were insisting we had consultant write needless and expensive reports , I am loathed to entertain them for a field access (apologies if there are any planning officers reading this). many thanks

Thank you!

Thanks all! Really helpful as always.

Thanks all - really helpful. is there any issue with build machinery driving over the new drain? It will only be 600mm deep to get over the culvert.

Hi. out build is set back 60m from the road and has to cross and culvert to get to the main sewer. We are going to have a pump to the boundary and then gravity from the boundary over the culvert and into the main sewer. All good. except, I am struggling to find a main contractor and have national grid ready to put the TBS in. I don’t want to keep digging up over the culvert for fear someone might crack it with their mini digger. is it sensible to put the services in over the culvert now (drain just from boundary to road with the pump etc from house to boundary to be done later once foundations are done)? Once the build work starts the culvert will be used for access so that will make putting services in tricky too? also, I have a Anglian water approved drain person lined up for the road connection. I assume the contractor can do the rest as it is on private land? I am eager to get on but don’t want to cause problems down the line.

Thanks all. I was already thinking I needed to get a ground worker in. I am desperate to get started on services given the lead time with the utility companies. unfortunately there are not many new builds around here and we have already got in touch with all of those builders. can anyone recommend a ground worker for a timber frame near Peterborough?

So we have spent 18 months getting planning, SE and BC approval. It is a 320m timber frame aiming for passivhaus house. We have gone out to tender to 6 firms who were interested initially. Now I have sent the 52 drawings the architect has done to get BC approval, no-one willing to quote. We are using MBC for frame and GBS for windows and I have listed some other preferred suppliers for aluminium roof, renewals, MVHR and kitchen/flooring. The feedback is despite being very keen 3 weeks ago they are now super busy or the project is suddenly too small (I think they mean because the frame etc is being done by someone else even though I did tell them this last year when doing my initial vetting). the architect lead us down the path of a super detailed tender process which seems to have been a waste of several months not to mention the £££. But to be fair we did need all the details for the BC. any advice on how to find a contractor for the wrap around of a timber frame? Whilst I don’t mind project managing I have no practical experience or skills whatsoever so need to outsource the actual work to people who can work off the very detailed plans. ps the foundations are Tetris block and beam for the passive.