Mulberry View

This is an important response for us because, if true, then it changes everything. So, it might be the case that we won't fit UFH upstairs at all. We are planning fan coils for the 2 first floor bedrooms, perhaps we just use fan coils for the bathrooms too? We have plenty of opportunity to conceal them and just have grille outlets. We'd probably add an in-wall electric heat pad of some sort to act as a towel warmer. I think you might have really helped here @JohnMo. The reduction in agro and the improvement in the reliability of the floor point to this.

This is the way in my opinion. I've been using the stuff a bit recently and did just that. Once it's partly gone off, it'll drop out of the bucket nicely. You're right though, it goes off VERY fast in this weather.

I'm guided by a low datum too. My bathroom window is floor-to-ceiling and with a 50mm frame height, so my total is 40-45mm in reality to include a structural layer. Damn I wish I hadn't got rid of the frame packer under it, but in all fairness, 45mm does work well with adjoining rooms anyway as I'm going from Microcement in the bathroom to thick carpet in the bedroom.

I recommend Soudal Fix All, I've used it on EPS with no issues. Sticks EPS to other surfaces really well. An easily available one if you don't want to think too much about it. https://www.screwfix.com/p/soudal-fix-all-high-tack-hybrid-polymer-adhesive-white-290ml/64585?gclsrc=aw.ds&gad_source=1&gad_campaignid=895557794&gbraid=0AAAAAD8IdPxQZcwfDg7XuWT6M7XU5qJW_&gclid=CjwKCAjw8uTQBhAdEiwAVvtJytd5T8metMhSfttfGiRHNorqe-zWY_O6Zos9P_4E07LqWha0FGRpwRoCSywQAvD_BwE Other options are Illbruck SP350.. https://www.dortechdirect.co.uk/catalog/product/view/id/742.html?gad_source=1&gad_campaignid=17178602520&gbraid=0AAAAADt-Kn0ph4eAt3inbtCk9Tjt8IA77&gclid=CjwKCAjw8uTQBhAdEiwAVvtJyrHurwMiX1eVezExj4zWyNFuYLzJ_LObPlYyH2qK77MUmOXTMa0tLBoCF0gQAvD_BwE But it was quite thick when I used it earlier in the year, so I'd suggest warming the tubes first.... Or this stuff if you can weigh it down whilst it cures as it is low expansion, but has been good at stick EPS to concrete etc. https://ewistore.co.uk/shop/external-wall-insulation/eps-adhesive-ewi-240-750ml/

Here's an in-progress Posi design for my Car Port roof. What I'm trying to achieve is a minimal edge detail, with masonry running up to the roofline, just with an Aluminium trim as a termination. What is the normal way to run the timber construction to the edge at the ridge and verge? So far the joists have been designed to land on a wall-plate on the inner leaf and the Posi tails have been left long enough to be trimmed inside the outer leaf, but I guess there will need to be some sort of rim-edge timber detail to support the deck and allow the edge trim to be fixed. At the verge, I am minded to have the last Posi swapped out for a 253mm Glulam, where a ladder frame can be built, but again I'm unsure how to detail this at the edge to achieve the minimal look I'm after. This is how the house is detailed, I'm after a similar effect with the Car Port, but here it's masonry not ICF! Obviously this is an uninsulated roof. Does anyone have any pics/details they can share to help me to move forwards with this? I greatly appreciate any/all help.

That's all very true and we had all the best intentions out the outset of the project. It was never our intention to end up in this much pain. We instructed Architect #1 in December of 2021, by the February we had already become concerned about a difficult working relationship. Something there was really no way we could have spotted earlier. She was a handful, very opinionated but oddly never wanted to come to site. It's a tricky site, with level changes and lots of trees, which was all documented in the Topo, but what we didn't think to consider and neither did she (because she never came here) was the magnitude of trees in the neighbouring gardens that would be impactful on the design. When it dawned on me, I called it out and she played it down. I ended up having to fudge a "topo addendum" of sorts, plotting estimated tree positions and approximate heights from our garden. It was clear at this point that we weren't getting the service befitting of the fee we had agreed (£16,000 for Riba Stage 4a). We plodded on through the difficult relationship, with all concerns and queries getting played down and brushed aside. After a massive mistake in ground levels on the plans (the building was drawn 700mm too high out of the ground), we really were getting annoyed. Long story short, we had to call it. The attitude was unbearable, it was pushed myself and SWMBO into tension and that's something we will not tolerate. So, with planning permission in hand, we broke lose and initially felt liberated. However, it soon because obvious that we needed further details/drawings and I think we can all understand just how reluctant any professional is to take on someone else's work, and so began the turbulent journey of trying to get our remaining detailing done. We "interviewed" 5 Architects in choosing the one we went with, she had us thoroughly convinced, she truly seemed to get it, us and the site. How wrong we were. That was just the start of our problems, but I think most of it stems back to that. Having an Architect who is not truly on your team is, I think, the most fundamental "clunk" in a self-build journey. The guy this post is about was technically Architect #3. Architect #2 turned out to be almost as bad as Architect #1, but now we are back with the firm of Architect #2, but with Architect #4, a really good guy and he's been worth his weight in gold.

There are lots of pitfalls in such a technical roof system, it really is a mine-field. I have plenty to say on it, perhaps that's for a separate topic! But suffice to say, the guarantees, on Zinc at least, are far from what they're claimed to be.

My lasting opinion of Zinc as a roof topping is, regardless of the problems I have had, you WILL get oil-canning. So if you (or anyone reading this) are looking at Zinc and are someone who might be bothered by this, then I suggest you have you expectations ready for it. My roofs are not seen from the ground from any position other than from one window inside the building and from that window you get the best (worst?) view of how bad this can be. Aside from all the other problems, I would not be content with the view I'll get every time I go upstairs and look left out of the window. I absolutely would not even contemplate it for a vertical facade, but I'd drawn this line in the sand long before our problematic roof installation. I have landed on the opinion that I would much prefer a nicely installed single-ply roof than a flawed Zinc roof and by their nature, Zinc is not flawless ever in my view.

Thank you, but we'll definitely not be going for Zinc again. I've totally lost the love for it and just wish we'd looked at other options from the outset.

A very expensive but poorly detailed Zinc roof. I posted about it here and there is another post linked in that post too.

I'm sure my proper UFH design will uncover that 40w/m2 is far too much. See my reply to @SimonD below. Thanks for your input, BH has been great to me, the support is helping me keep my head above the water (just about!).

In fairness, this is an outline quote, we're not at design stage yet so a set of heat loss calculations has not yet been done. I guess they'll charge for that in the end? I'm trying to do that myself through Heatpunk, but it's tricky with my very irregular shaped house. I'm considering paying for the Pro level for a month or two so I can upload my plans! But that doesn't help with ceiling levels (I have sloped ceilings). I haven't added all the windows yet, but it looks like 21w/m2 on there at the minute.

Thanks for this @Gus Potter. I'm a very very patient guy. I am possibly too far into the details, but I gave this guy so many chances, we communicated loads. I provided additional photos and dimensions as were needed to articulate the as-built structure. I spent FAR too long trying to mock layouts up in ChatGPT to try to further illustrate points I felt the Architect had missed. The fundamentals were missing though, without adherence to the standard details of the roofing system, we needed to go all the way back to square one and the passage of time thus far made it feel too risky to do with how weakly applied this guy was. With the idea that the ZInc roof needs to be stripped, part of my brief was to try to retain the Plywood deck if possible, as "taking the lid off" and seeing daylight from inside again felt like too much regression and another layer of waste that might have been able to be avoided. I already have 170sqm of 200mm Celotex that I cannot reuse. This might be why he couldn't have oversailed the edge to provide a similar detail as the one you kindly posted. I also now realise he's not as experienced as I initially believed. Keep in mind the total quote was £4000+VAT. FOUR THOUSAND POUNDS to provide a set of 6-8 details. Many people do not pay this for their whole Architectural package. I was desperately in need of help and believed this guy could take some of the stress off my shoulders. Turned out he just added to the ever-growing pile of nonsense that we're battling. We've lost tens of thousands of pounds in this project on "leakage". Poor Architects and this whole roofing debacle being at the forefront. Those elements have BY FAR been harder than physically standing this place up, even at my experience level. Some of the things I have achieved in this build make me proud, dimensional accuracy, level and having 3 ground floor levels that are +/- 10mm from the planned levels being some of them. Why can't professional services take the pride in their work as standard and just do the right thing if the customer isn't happy (and brings justification)?

Sadly, to our detriment, we do not have legal cover. This emerged during the early stages of the legal action that is still ongoing with the defective Zinc roof. We live and learn!

Although I need to look more closely at the quote, they've based the whole-house design on 40w/m2. I'm guessing that 10.5mm pipe at 75mm spacing is similar output as 16mm pipe at 150mm spacing. You're right though, this is more to give a warm feeling to the floor and what little bit of heat input might be needed.

Yes, they prescribe 10.5mm pipe for 17mm total, or 16mm pipe for 25mm total. I'd like to try to make the UFH/Screed/Microcement layer compatible with thick carpet/underlay in adjoining room, so figured that 21mm total would work well against underlay and carpet. We don't need loads of heat in there. I also have a floor to ceiling window with only 50-55mm of frame to play with. The 10.5mm pipe solution gives me 41mm, the 16mm pipe would be 51mm.

The only issue for me is that I can't accommodate that thickness of screed. However, I could go for a "halfway house" with the Roth system and their fibre reinforced liquid leveller (or another similar product), which they rate at 17mm total system thickness, so it'll be a few mm thicker by getting rid of the plastic grids. That's obviously not 16mm pipe though.

Interesting thought. Seems quite reasonable. Are the grids just for installation convenience? As long as the Chipboard is sufficiently waterproof... Is that a Chipboard floor with a DPM then UFH pipes?

You'll notice from my wording that I said "I wondered". It was a fragment of my own uneducated thought process.

That's all very helpful. My small first floor is designed to have acoustic insulation under it, but I also realise that will block some of the heat rising from the ground floor. I had, however, wondered whether it might be a good idea to add some sort of reflective layer between the Chipboard and the "egg crate" system, what do you think?

I agree with that sentiment, I'm the king of overkill, which is why I have 253x145 joists at 400 centres under this bathroom, with a 5m span and strongbacks in there too. It doesn't budge.

Egg box overlay? So like this??... https://www.roth-uk.com/products/low-level-overlay-system/roth-quicktemp-climacomfort-system That system has as low as 17mm total build-up when using 10mm pipes at 75mm centres and their fibre-reinforced leveller. Forcrete Microcement could, I think, go directly over this and the 21mm height off the top of the Chipboard would work well with the adjoining carpet/underlay if we go that way. My Ensuite is a reasonable size (around 3.0x3.0)

Following on from our Architectural woes (we had to part ways with our original Architect). I instructed an Architect to handle the re-detailing of our roof as the Zinc scheme that was installed 2 years ago has to be ripped off. The assignment was a fixed scope, to provide replacement details to cover all areas of the Zinc roof but with Sika SGK membrane, I had obtained a spec from Sika which was in hand. I was very open and candid about the as-built structure and the pain points. I provided lots of photos, plans and a detailed narrative all in advance of the quote. I explicitly told him that I needed decisive details, as I don't have the headspace to do this myself. The Architect quoted, I agreed and paid 50% up front as requested. The suggested timeframe was 4-6 weeks. It quickly emerged that the Architect was not confident. He flitted between solutions and relied upon me far too much to back him up. 5-6 months later, we still did not have a workable set of details that were efficiently buildable and conformed with Sikas standard details. After much patience, I called a halt and raised a dispute. After some backwards and forwards emails, the Architect has agreed to waive the remaining 50% fee, but insists that the 50% up front is payment for time spent. This is an example of the details produced... There is far more timber in here than the alternative detailing and much of that is not practical in my view. Besides, the Aluminium edge drip trim arrangement doesn't conform to Sika's detailing and for their own trim that is the only one they allow. This is the alternative that I now have in hand (not quite finished but you get the idea). Far simpler and compliant with the manufacturers requirements.... As I understand it, payment for time spent is not a thing with fixed-scope/fixed-fee work? Nothing about payment for time spent was discussed in a email "contract". I have nothing usable from his detailing and have since found a good Architect who has already pretty much re-detailed it proving it can be done. I'm not prepared to let the £2400 I've paid this guy just slip away. I'd appreciate any advice on this.

We're building a 200sqm Nudura house, around 135sqm gross ground floor, 230mm PIR over B&B floor. In-screed UFH with around 50mm of liquid screed is looking likely. First floor is just a Master Bedroom, Master Ensuite and a second Bedroom with a small Ensuite, around 65sqm total. We like warm floors in the Bathrooms, so are thinking of going for Roth Clima Comfort mats with 10.5mm pipe over the 22mm Chipboard, their liquid screed over that as it'll make a nice substrate for the Microcement (that SWMBO simply will not compromise on). The Bathrooms are back-to-back and the Posi design is super-rigid. Does anyone have experience of this type of system for first floor? I gather we have to have some sort of emitter in the Bedrooms to qualify for the BUS grant? But we want nice carpets (not limited to 2.5tog), so the option I guess is UFH and just accept the performance loss (the heating will be minimal anyway) or fan coils, but we lose wall area with these I guess? I realise the upstairs heating is debatable for most people, but I don't think we can go for no heating at all up there, I'd hate to have to do something retrospectively. Also, what type of pipe? Roth have quoted for PE-RT (they have an Alu option but say it's overkill), Continal suggest PE-RT/AL/PE-RT....

As a follow-up to this, I replaced the PRV (cost about £20 locally). Really was a pretty easy job, certainly isolating and draining the boiler was the tricky bit but only because I didn't have a suitable piece of hose at first to allow me to drain the boiler into a bowl/sink. I repressurised the EV. This was about 2 weeks ago, the system is still holding 1.5bar. I'm sure I'm not in the clear, but it seems OK. So we'll see how it goes. Thanks @Nickfromwales