Andeh

Not sure what a solum is? The walls are cavity built off the foundations, with 100mm thick polystyrene insulation below DPC (so 300mm+ to bottom of beams which sit on DPC + blocks which sit on DPC as well). Beam & block then sit on inner wall, with twin breeze block built from here upwards with Knauf dritherm in the cavity. If that makes a difference? It's a full block built house, no timber until you hit the roof.

We are building a large bungalow, our garden has a slight incline to the peak of a hill above the property. Prob 5-7m total height change over 60m odd as we look out & up. Block & beam, with around 400-600mm space under the beams. Roof on, windows about to go in. Pretty heavy clay soil under a few feet of typical soil. What we seem to be getting is mysterious water appearing under the garage aspect of the house. I lifted up a block for the first time in a month, and found there to be about 4" of water trapped there - this has worried me as I expected it to be bone dry as the roof has been on for the couple of months since I last checked. I imagine rest of the place is similar though I cant check as UFH & screed is all in now. I am wondering if it could be a higher water table when it rains heavily, or water flowing down the hill in the soil and then seeping into some of the blocks and puddling under the floor? There back garage wall is very wet from lack of roof guttering, so it would be getting in via this way as well. Air flow is 'fine' to the sub floor - ie; not perfect as we lost a couple of air bricks due to patio changes, but there is still free flowing air in & out to all cavities under the house. No space is without air flow. Is this normal? How do average builds built over winter (like today when we have had 2cm of rain....) cope with the water getting under there and being trapped? Damp proof was all immaculately installed & maintained, so no risks there.. I'm not sure what I am worried about, just dont like the idea of water underneath? Has anyone ever thought about this themselves? Many thanks in advance

We had a 1970s place that had pvc soffits over ACM ones. Not dissimilar to yours in style. Only cost about £900 odd for full perimeter soffit removal and disposal., (vs like £4500 for architects recommended company). Got all the paperwork for proper disposal and they were registered.

If sealed off fully, the air pocket would prob help!

0.9 is exceptionally low for Aluminium! I recognise that style within the Alitherm range, though we didn't consider it to be honest. One thing I will wish we had done (rose tinted glasses n' all...) is put more thought into the windows. Shopping around, more styles, alternative materials etc etc. I think I was probably a bit too stubborn/decisive in ruling out 'anything plastic' on a high end house after years of living with the very worst PVC in new builds, and then leaving the builder to find the right style/type of window! Not that I am unhappy with the Alitherm and the style - we really like it-. Just that itch I have that I like to research & double check everything, which i wasn't able to do here*. *that being said, when you approach 7 window providers to quote and all either decline or ghosted us/the builder, and the clock rapidly running down.... it does limit this somewhat.

We have the alitherm 600,and managed to get the overall average u down to 1.4 with laminate, low e class and some filling. Nit great, but better then the 1.6 we were looking at. Were due to this, 3 week delay due to laminated now.

Good luck!

I almost DIYd it myself (my other thread from the weekend) having spent some time on YouTube. If you have webbed joists and an extra set of hands, I really don't see it too complicated. Commissioning being trickier, but something that can be figured out further down the line.

Some very large tarps over the roof, screwed down with wood? Not so much dry it out, as stop more rain getting in!

Welcome and good luck!!

We found a local guy, who was about half of the quote builder came through with. Fortunately in very quick succession we confirmed the quote, found slots in his diary and IN THEORY it's only a 1 week delay by the time he installs come 3rd December. Just good fortunate I got quotes a couple of months ago as a precautionary plan B!!! Still a chunk of £2500 materials more then we intended, but a lot less then builder quotes via CEF. Im on my 2nd g&t this evening... Damage recovery mode continues....

Yes, we watch it almost for the 'at least we' re not alone' assurances as we progress our own build. Though I have to admit, I can only really watch it after a very large gin!! Some bits do hit too close to home....

I don't know enough about PIR, is this in case of another grenfel fire spread issue?

Damaging UFH pipe is rare, it's very durable and resistant to abuse. Any reason why it could be damaged? Bricks dropped on it, heavy metal work, revenge/spite?

Yes the low profile UFH do heat up faster, yours times are about right vs our low profile retrofit system, but for such a well Insulated house I don't really see the value on that vs just Ufh in screed and setting the temp to 18 degrees and leaving as is.

Yeah, up until now everything has been on a fixed price more or less, this MVHR has been the first real scare tbh. The price up front was keen & the quality of him/his team has been very good so happy over all. For this MVHR though -I do agree!

I presume where kits are ''left hand'' it means some of the ports are on the left hand unit and some on top -vs- them ALL being on top?

Thank you so much guys!! Just builder dropped the ball I think, he originally estimated £3k to supply (nearly 18 months ago admittedly) and CEF have come in at £9100. I'm meeting him next week to discuss, but it generally works as he does all the bricks, mortar & construction stuff then he gets a couple of quotes from 'big' firms to do supply & install on the specialist stuff...ASHP, UFH, Roof, MVHR, etc etc and goes with the cheapest.... I dont disagree with this approach as specialist doing specialist work, but in this instance the MVHR quotes are too much for me to just accept. Turns out I ran a quote from BPC which came back at £4500 odd a few months ago which I am pleased with (completely forgot). That was for one large unit, when I will need two smaller units, but it has at least given me some that I can salvage something here. Do BPC do the full design & supply....and you simply follow the instructions & adapt it on the day for the specific properties needs? Im hoping as it's ''just'' a tall bungalow, warm roof (though block internal walls) and webbed joists the installation shouldnt be that complicated!

Just add whats daunting, is I dont see it as a complicated system...but when I look at the CEF quote thats killing us, it makes it feel very complicated!? MVHR 9100 quote.pdf

Hi all, Slight emergency for us in the sense our builder has just dropped a clanger that the MVHR he originally costed for £5700 supply & fit is now coming back to us at double this!! With plasterboarding on the horizon, I have very limited time to try and find alternatives, even though I have a couple of historical quotes from local suppliers for nearly 50% saving, though I am quite sure their timing would push the plasterboarding & project back a good few weeks - a very hard conversation I am losing with my wife. As a result i'm stuck between a £4k bill to meet the timings, or save £4k and incur rent & hassle for probably a good few weeks - as a result I am looking at DIY. I am pretty good with DIY and am very hands on, running the pipework seems fair enough. In terms of how I design the system I am concerned though. Some quotes have shown ''Y junctions' within the fabric of the ceiling, when I just thought all pipes would naturally run back to the central unit & a manifold there? Looking at Vent Axia Sentinel & a second compact one for the two halves of the house, as per floor plan attached. Low height central entrance prevents one unit being used. Just welcome how others approached this & how DIY start was researched on design, supply, and any 'gotchas' found when DIYing a MVHR system? Ironically enough, money is no real object when I look at a £4-5k discrepancy between Builder's CEF quote & my historical quotes from a couple of months ago.... 3180_s4_100J_Floor Plan.pdf

Probably exactly the same place as you OP. Been at it for 12 months now, should have finished in July... Now hoping to make January. Just feeling like it's a never ending slog. We took a £6k hit yesterday on material pricing which is still hurting, but builder and his team are good. Each phase had its own ups and downs was delighted to get the roof finished after much delays... Only to run into delays on windows. One hand giveth, other hand taketh away. It's a marathon for sure, one day, one week at a time.. Head down and persevering.

Love it, good progress! You look to be a couple weeks ahead of us....we are waiting on windows !

Thanks, due to bungalow it needs to be a flat/low profile one!

Thank you very much, this is exactly the sort of thing I was hoping for....!! Have you got any pics of the installation? Is the drain on it replacable with one we have chosen? Thank you!

Doesn't bode well, I had hoped they were more common?