jack

Meddings is similar quality to Fobco. This is presently for auction: https://www.apexauctions.co.uk/auction/itemDetails/2427/247632#

Isn't at least the bottom layer structural though? It's supporting the weight of the window.

All sounds very sensible. If you think you have a reasonable chance of meeting the Passivhaus standard, then you shouldn't need anything very big. Ours is a 5kW Aquarea with a bigger floor area and it seems to cope perfectly well with combined UFH heating and hot water duties. Our plumber was mortified when we proposed such a small capacity unit - he had assumed something like a 12kW number would be required based on the size of the house. I showed him the numbers, but he was still concerned about the house cooling down during the couple of hours each morning that the ASHP is heating the tank. I pointed out that it takes a day or so for the temperature to fall by 1-2 degrees. He still didn't believe me. As many of us have discovered, heating is the easy part with Passivhaus Standard levels of insulation and airtightness. Hot water becomes the dominant energy consumer, so you may wish to optimise your plans for that function.

For branches of any real size, I think petrol is a given. We have one of the Bosch slow speed ones (the slightly smaller/older version of this). Instead of using a high speed blade to slash/chop, this uses a slow, high torque wheel with cutting blades on its outer rim. Mine can cut up about 1-1.25" from memory. It's very slow, but I can't tell you how satisfying it is watching one of these things slowly drag in and consume an entire branch. Also, although it seems slow, it's amazing how much you get through. You tend to start one thing on its way, and while it's being drawn inexorably to its demise, you turn and get the next victim. Quite therapeutic in its own way... Good for bushes, brambles, thinnings and small branches. It's also very, very quiet, unlike some of the high speed inertial ones.

Welcome. A couple of points: 12kW of PV sounds like a lot, but you'll generate surprisingly little during the darkest months. We have 8.5kW and this was what 2016 looked like: December only managed 146kWh, or less than 5kWh per day on average (we had a few days where we barely got above 1kWh). That's less than two hours of a standard 3kW immersion heater on full bore. We have a 289m2 close-to-Passivhaus Standard house with a 5kW Panasonic ASHP, which covers hot water and underfloor heating. It cost about £1800 + VAT and our electrician and plumbers installed it (monobloc ASHPs are a doddle to install) in a few hours. The ASHP doesn't come on for probably 6 months of the year due to the PV supplying power to an immersion diverter in our unvented hot water tank. The only reason I can see for such a high package cost is if you're using an RHI installer. The process does involve a lot of paperwork and keeping up certifications. That and the payback seems to have encouraged much higher prices from installers signed up to the scheme. Solar thermal is expensive, requires maintenance, and tends to spend a lot of time generating no hot water or far too much hot water. Since you already have PV, you can use an immersion diverter put excess solar energy into a hot water tank. I believe it'll make hot water for a higher number of days than even the best solar thermal. Seems a no brainer if you already have the PV in place.

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).