Bramco

If you look on the IKEA website, the full installation instructions will be there

Hasn't Velux become the generic name for rooflights, in the same way that Hoover has become the generic name for vacuum cleaners

So are we going to get any photos of the finished article?

@Great_scot_selfbuild Timber cladding is larch treated with SiOO:X which stops it greying -> https://www.russwood.co.uk. It actually gets lighter over time.

@Great_scot_selfbuild - thanks, I'll tell the builders next time I see them. Those saris rooflights look exactly the same as the Roofmaker rooflights we used -> https://roof-maker.co.uk/products/hinged-opening-flat-rooflights/. Think they do these in a variety of glass types/u values. Ours are triple glazed as in the link and work very well. On the blinds aspect, ours are in the living space and bathrooms and on a landing, so we're not worried about having blinds. Wonder if @JamesP has blinds? If you're thinking blinds to cut out solar gain, then maybe it would be enough to simply open the roof lights to dissipate the heat. Works for us. The cladding is Greencoat (afaik) specced for longevity. I can check the exact spec if you need that. Here's a link to the architect's web site with more photos -> https://lhc.net/projects/ashcroft-creating-a-low-energy-family-home/

@Great_scot_selfbuild We didn't use Velux - hate the stand up edges. We did use the Roofmaker skylights that it looks like you have used on your garage. Ours are flush with the corrugated roof. Essentially you have to leave a large gap at the bottom of the roof light, create a slight slope and then mold a water resistant membrane across that and onto the top edge of the roof below the roof-light. Ill have to check with the builder and architect what we eventually used - was 3 years ago. EDIT: checked and we used -> https://www.deks.co.uk/fast-flash See photo - I have the architects drawings for this if you DM me. PS What's the reason for using Velux rather than the Roofmaker roof-lights?

Not sure why a brick or block skin would be seen to be giving more surety - it's only a skin and the fabric is timber frame. Just goes to show how thick industries like insurance etc. can be at times... I wonder how everyone in Scotland copes? What with timber frame being much more prevalent there - afaik. Have you tried Scottish mortgage companies? Also, isn't there a timber frame manufacturers association? It may be worth contacting them. Or just going round to a local building site - there's a lot of timber frame going up at the moment - how are they advising their clients on mortgages? Or take out a buy-to-let mortgage on the property - and get a postbox address for correspondence.... 😉 🙂

Yes it's essential in a house which is nearly airtight - and if you are self building and don't intend to make things nearly airtight, then you've got to be daft because all of your heat will disappear into the environment through the draughts. But you need either a good builder, or a lot of patience to get the airtightness. And a lot of attention to details - window frames should not have vents etc. Air quality internally should be much better as well as the air entering the house has been filtered.

Would be interesting to see the last charts by Battery kW, then cost per SAP point. In terms of our thinking, 5kW of battery wasn't going to achieve a lot but then deciding whether to go 10 or 15 was. Same goes, I guess, for PV. The costs of installing 2kWp would be crazy and that shows I think in the earlier sheets.

Sizing the inverter depends on few things - what is the maximum PV output, what is the maximum draw from the house etc. Given you'll almost never get the maximum PV output and the estimated output is 6kW, you'd be OK with a 6kW inverter. On the house side, the biggest draw from appliances is about 3kW, so you could draw 6kW from the batteries without pulling anything from the grid. But if you want a fast EV charger, they would pull more but then it would depend on what the batteries can deliver. Don't know what Sigenergy can do but it will be on the spec. If you plan to do EV charging from off peak, at night, then this might not matter. Personally I'd put more battery capacity in rather than a larger inverter. If you are on O Go Int, then you can dump almost everything in the batteries in the evening at 15p before the cheap rate starts and then refill them at 7p. It's a bit of a no brainer. So the larger your batteries, the more you gain. Having said that, we are single phase, so I don't know how this would work with 3 phase.

The way we use the thermostats is really only for the scheduling and as temp limiters. The thermostat schedules (3) are set to come on just after the start of the cheap rate and are set in one hour chunks. First hour is at 24C then we drop gradually hour by hour down and the last hours are at 22C. This ensures that the thermostats don't do their stop start business, so the ASHP is on constantly until the target temperature is reached. Seems to work for us. If we dropped the thermostats and went over to WC with a setpoint, then we'd have to find some other way of scheduling the night time batch charging of the slab. So we'll stick with the thermostats.

So the hot side of the house can't take any heat but the cold side can - so any flow through the hot side comes back still hot whereas the flow through the cool side comes back cooler. Trying to get my head round how this would work for those of us with insulated slabs with UFH that batch charge the slab at night on cheap rate lekky. I guess the same would happen - loops in cooler parts of the slab would suck up more heat than those in warmer parts. So the only setting is the setpoint set on the ASHP. What is yours set to against the temperature you are trying to achieve in the house?

You obviously live alone... Where thermostats have a display, isn't that what the display is?

You're making the assumption that someone in the house (you know who I'm talking about) can guess the temperature without looking at the app - ain't gonna happen..... 😄

Could do but... In our setup, we only need to run the ASHP at night to batch charge the insulated slab. When it is cold, all the rooms need the full 6 hours or so. When it is less cold, the thermostats will cut off the flow when the set temperature is reached. So for the downstairs bedroom it cuts the flow off earlier than the other two living area zones - the set point is lower. I do set the thermostats in 1 hour intervals starting a couple of degrees higher than needed and decreasing the setpoint every hour. This makes sure that the thermostats don't dick around with the ASHP by tuning it on and off at short intervals. Again this seems to work fine.