jack

Something serious has gone amiss here. Not the kind of stress anyone needs during a build! I have every confidence in Joe and Brendan though. All the best for a speedy and successful resolution. Having just looked back again, I'm surprised that the windows fitters would just press ahead with installation given there's clearly something serious going on. Were they really packing up ends of windows by tens of mm relative to the floor rather than just stopping and telling you to get onsite?

Who are you and what have you done with @Onoff?!

Makes even more sense in Australia given the high levels of insolation compared to the UK. From memory you generate something like 50%+ more per annum for a given installation somewhere like Sydney. Interestingly, one of the biggest power drains is air conditioning. Since it's generally sunny when it's hot, load matching is a lot better than in the UK, where we need little cooling in summer but (for the average house) a lot of heat in winter. We paid something like £600 for our utilities last year. I guess I could get that below £500 with only minor tweaking and lifestyle changes. For a low energy house, the payback just doesn't make economic sense at the moment. Maybe in a few years when the price falls a further 50%...

Aaaaarrgh!!! Good luck!

Looks good, many thanks for that.

Interesting, thanks. If you happen to come across it, that'd be great. I'm still puzzling over exactly how to handle mine, which is frameless glass like yours (into an extruded aluminium channel - is the grey strip along the bottom of yours a channel like that?)

Lovely stuff. We have an almost identical balcony to our bedroom. On that point, any chance you might share details (particularly sections) of your balcony, especially the balustrade mounting and flooring detail? Your cladding looks a lot better than ours. We have Siberian larch. I've been interested to learn that weathering is at least, if not more, driven by exposure to rain than sun. This means that under every overhang we have a diagonal line where the rain gets to. I expected weathering gradients under the overhangs due to the sun, but thought they'd be a lot more of a transition than a messy line.

We're at 25.5 downstairs and 26.5 upstairs. Far too warm. Part of this is the eastern facade getting a long period of morning sun, and not having any shading on half of the windows. I'm looking at setting up some temporary shading just to keep the sun out for the next few weeks. Also looking at buying some fans for bedrooms at the moment, as getting to sleep is starting to become uncomfortable. I've also realised in the last week that something seems to be wrong with the MVHR summer bypass mode. It works fine if you switch it on manually, but the automatic setting doesn't seem to be working. Need to contact the supplier for input!

MBC built a house on top of @Bitpipe's separately constructed basement. Is that the sort of thing you're doing?

"You could do what what we did" was meant to be a joke. Defo wouldn't recommend it as a general approach, but we weren't given any option by the demolition guys!

You could do what we did and come home to find that your demolition contractor has just cut it with shears and left it dangling at the bottom of the telegraph pole across the road (something we only noticed about a week after the demolition!) We tidied it up and left it in the end, then just got BT to reconnect it (via Openreach) as a new line. Surprisingly all was fine.

Based on 20 floors at 3m per floor, and guessing that the building footprint is about 25m x 25m, you end up with 6000m2 of surface area including windows.2 Rough estimate for windows is maybe 25% of the facade, so 4500m2. Call it 5000m2 and you're looking at £1/m2 extra for fire-resistant insulation (assuming no extra costs for installation). Is that a realistic price difference?

What options are there for truly non-combustible materials in this role (retrofitting EWI to high rise buildings)? The main advantage of most rigid insulation materials is that they're cheap, light and completely self-supporting, so ideal for this role other than the fire risk. Are truly non-combustible versions of these materials available? It's far too expensive at the moment, but when aerogel sheet (not the blanket stuff you can get now) eventually becomes available in bulk, it may be suitable for this application, given that aerogel is even lighter than, eg, EPS, has a better U-value than any other common insulation, and is utterly incombustible.

The void is on the outside of the insulation: wall->insulation->gap->cladding

It will be interesting to see whether aluminium was used to replace the approved zinc without approval.

No, I don't think so. The MVHR blows air away from the wall due to the fan, so the cold air will tend not to hang around against the wall. Ambient air is sucked into the back from all directions. Unless the whole area is a confined space (eg, a corridor that doesn't get any breeze), I'd be surprised if there's much overall impact. Even if the area is slightly cooler due to the ASHP, it shouldn't have much impact on the MVHR. At 80% MVHR efficiency, and, say, 2 degree lower temp (due to the ASHP) at the outdoor MVHR inlet, the supply temp inside will be at worst 0.4 degrees lower than if the MVHR wasn't there.

Fridge for everything except potatoes, onions and garlic. Potatoes do tend to sprout pretty quickly, so we try not have them lying around for long.

Ah, right. All widths were perfect for us, but we had quite a few height issues.

I can't recall - are you using a main contractor? Either way, did the person who installed them supply them?

I'm sure my Panasonic Aquarea ASHP installation manual cautions against using cooling mode to cool UFH heating circuits. That may be arse-covering though. We haven't bothered with cooling yet. It's not that hot downstairs, and I doubt whether cooling the slab downstairs will have much impact on the bedroom temps (which are the only ones I'd really like to bring down at times).

I'm so glad my experience has helped someone else, and very pleased you found the issue now rather than later. MBC came out on the same day the errors were discovered by the window installers, to adjust the two or three worst of ours. The rest were fine, as there was quite a lot of tolerance built in (eg, window aperture was nominally 30mm taller than the external window frame dimension, but was built to 18-25mm). Interesting yours were mostly upstairs - ours were too. Was it vertical dimensions that were the problem? Good catch on the slab recesses. Fixing those after the fact could involve a world of unpleasantness.

@craig, the quotes actually didn't change, we just needed to split a couple of windows into two leaves rather than one. I can't fault the (German) manufacturer - their product is very high quality, and they were a pleasure to work with (the MD sat with our architect for two hours going through installation details and provided some very helpful ideas). The installers, unfortunately, did a poor job. Missed that the windows were to be packed up by 15mm to allow fitment of cills, which meant we had to hack off the edge of the cavity closers to make space. Then it turned out that they hadn't realised they needed access from the side to mount the external blind rails to the window frame, so I had to go around taking of all the exterior battens. They left on the the morning of day 5 of a fixed price "5 to 6" day job, then demanded full payment for travel time (they came over from Ireland) and accommodation to come back and finish the job when the issues above were identified. To add insult to injury, I found out some weeks later when I went to remove the cills to work on the butchered cavity closers that they'd obviously not had the right screws to hand to fix the cills, so they used construction adhesive to permanently attach them! I would never, ever consider having installation handled by anyone other than the window supplier. The opportunity for buck-passing and excuses is just too high.

Welcome Craig. I've recommended Ecowin/Gaulhofer to a couple of people in the past (one definitely used you) based on running into Thomas on my way out of Ecobuild a few years ago. I went with another supplier in the end, although it turned out that the reason we went with them over Ecowin was actually due to Thomas being more technically knowledgeable about his products than the people we went with! (Basically, he looked at our window schedule and pointed out that some of them weren't possible as openers due to their size. The other lot didn't realise this until we'd committed to using them and their technical department got more involved). Will use you next time, I promise!

We used them and I unreservedly agree with this sentiment. Out of all the trades we had onsite, we only had one person onsite (the electrician) who worked as hard or I trusted as much.

Welcome. Sounds like an unfortunate set of circumstances.