Radian

That looks like a schematic for a fully off-grid PV system to me. Perhaps you should draw a schematic for your setup.

Actually, the ideal would be an iris that could have its direction of airflow reversed - then I could mount it on the outside (it's very protected up there) - at least for the toilet extractor to make a push-me-pull-you. I suppose it could be boxed in ar$e about face outside but that'd probably end up being fugly. The utility room could be done with an iris the right way round inside but even the short elbow to outside is a cold bridge unless also damped outside.

A thermal picture paints a thousand words. This is the Utility room showing the ceiling extractor in the corner and the path of the duct located in the space between joists on its way over to the extractor in the loo: And the stacked outlets in the porch area outside: I could try replacing them with gravity flaps but I'm not happy about the idea of them.

As a general rule I never use the type of garden paints that form a skin. The only sort that seems to stay put is the type of paint intended for rough sawn timber i.e. fence paint. These just fade away rather than peel. That means they need no great amount of prep before repainting - which is always inevitable. Just a quick brush off and slap on some more. Much cheaper too, and often has a certain amount of wax content that shucks water off for a while.

Brilliant. I'm sure lots of people ignore Approved Document K when doing hard landscaping yet, as I understand things, does apply to anywhere being constructed that presents a danger from falling. Perhaps someone could correct me if not the case?

How high is it off the ground? If the drop on the other side of the glass balustrade is greater than 600mm Building Control should be involved.

I think this is mostly from losses in the Mosfet switching when the inverter is actually running off-grid, hence the reduced power when in 'search mode' This video shows the power saving modes at around 16m in: Good question. I'm not sure there are any inverters with the same kind of fully symmetric topology. But then Victron seem a lot more open about the design details (as per above video) so I might be missing some Chinese equivalent. As a UPS it looks perfect for my needs. I like that the 800VA model is only charging the battery at 16A (around 500W max from AC side) as it can be left to charge in parallel with my PV immersion diverter and replenish the approx. 1kWh I would be cycling through the battery every day, in a few hours on most days (it might be a simple as putting it on a timer to coincide with peak PV). My only reservations at the moment are having a noisy unit and a LiFePO4 battery indoors. The noise I can probably do something about with an acoustic treatment in the cupboard but the battery still makes me nervous.

Borderline amounts of airflow may be all that keeps condensation forming on your walls. Therefore where things cover the wall (e.g. hats) there's a build-up of moisture that the mould is thriving on. Additional vapor from your breath on the wall you sit at might also tip the balance. If it is such a fine balance it might be solvable with a small amount of additional ventilation. As for eliminating the mould, bleach solutions might not be enough. A 3% hydrogen peroxide solution (the standard percentage sold in pharmacies) would be my starting point. Stronger can be bought online if 3% doesn't clear it. Edit: just read you ventilate the place by opening windows - but to what? Must be a rainforest out there.

If that was correct it would be documented in the Manufacturers instructions for the channel system. Bet you won't find it. They usually spec. concrete screws that are tightened with a socket spanner as in this vid:

This is the typical kind of balls-up that happens when the architect's drawings don't reflect reality. Personally I'd be talking to the person who drew the plan and discuss issues to do with liability for the extra expense the error in capturing the building layout will incur. Perhaps one of our tame in-house practitioners might like to comment?

Sorry if I alarmed you as I just spotted I should have made that a 10kg point load (now edited). Clay is liable to heave but it depends on what other structures may be present/crossing the cable. The crush rating could be exceeded at any depth by a suitably massive load above, so it's a bit of a 'how long is a piece of string' question - without saying something like 'to withstand vehicles parking on it', or 'foot traffic', or 'just to support the clay above'.

What's the construction materials being used for the first floor then? I'm wondering how you can have a 70mm cavity up to first floor level - then a cavity wide enough to take 90mm of PIR board (plus a gap to the outer leaf).

1000N/10cm is 10N/1mm (sounds more butch over 10cm don't it). So you're looking at a point load of just over 1kg. Interesting but no answer to your question - which needs augmenting with the mass of the load, and the area it acts over. It could support any load you can dream of - if deep enough. Or maybe you mean the load is just the weight of the clay above? I doubt that's what you mean. (Oops, should have made that a 10kg point load)

So how wide is the ground floor cavity with the beads in it?

Wasup @SteamyTea? The diverter is looking at how much energy is being passed back to the grid via the little buffer simulated by the meter. I think you're expecting the local loading beyond the meter to have an influence on this - but it's all compensated for on a cyce-by-cycle basis. Yes, the changing voltage delta due to downstream loads will have an affect on the instantaneous current but the resulting power is being integrated and used at the end of the cycle to work out how much has gone into the buffer. Then the diverter will try pulling it back out of the grid by applying the appropriate load.

Or decentralised control, where the mains cycles are individually tagged for consumption and gobbled-up by anything 'listening' that can make use of them on a one-by-one basis 😉

So presumably your first floor wall will replicate the ground floor cavity wall in construction? If so, why not contract an EPS bead supplier to come and inject the new wall above so the beads will fill down to the old ones. The earlier EPS installations didn't use a bonding agent (PVA) so the beads settled over time. Nowadays they set rigid so neither settle or pour out if you core a hole. Also, by not putting cavity batts in the new wall, it will be cheaper and faster to build. EPS fill is fast and cheap!

I'd go with plastic. "Polyester reinforced bitumen" doesn't overcome my instincts regarding how bitumen degrades over time.

Alright, just how loud are these things in use? I was browsing some reviews and somebody said they could hear it through two fire doors! 😱

Have you looked at the Victron Energy MultiPlus range? I don't know where these fit in with the other hybrid inverters being mentioned but it sounds to me like the ideal grid supported battery source for this application. While generally marketed as a supply for boats that can operate from on-shore power and/or battery (it claims it can boost shore power) it's also frequently used in RV's and houses.

This is what I like about people sharing their opinions here. I'm always open to adoption 😃 Reminds me of when @SteamyTea mentioned how good value for money power actually was when compared to employing manual labour on minimum wage! (or words to that effect)

Thanks for pointing me to those. Didn't show up in searches for motorised vents although I'm rubbish at search terms. Flap shutters are the obvious answer I was waiting to be hit with - but they're too restrictive at the end of a long duct and also make an annoying racket when windy. The annoying thing is we're very happy with the extractor as it's got a nice chrome design with built-in illumination, and since I modded it with a PC fan, is almost silent. Still, it's good to see some more options.

Oh, so you 'cook' the stone first then stick the food on and grill from above. Very clever. That's the tricky bit I suppose - where it does a pizza in a few minutes, oven chips might take longer and possibly burn?

I've yet to see an intermittent extractor with a damper to close off the exhaust vent when not in use. Being intermittent, i.e. on a light switched timer, there's a clear 100mm path to the outside world for the vast majority of the time. Being surrounded by centrally heated rooms on all sides, our downstairs loo hasn't got a single outside wall yet it's always the second coldest room in the house. The extractor duct is run up through a boxed-in section in the adjacent utility room and exits near the back door alongside the extractor vent for the utility room - which is the coldest room in the house! It's blindingly obvious that it's the unwanted air exchange between these two rooms that is responsible. I'm reminded of this as the heating has yet to come on and while the house is staying passively above 20oC , the loo and utility are pretty much at average outdoor temperature - currently around 14oC. I've also commented here before about how after sanding a painted picnic table outside the back of the house, I came in to find an even layer of dust on the lid of the toilet and cistern that wasn't there before I started sanding. What I feel I need is a motorised damper similar to this kind of thing: But ideally it'd be integrated into the outdoor vent as there's no access to the ductwork other than by taking down some of the ceiling. What bothers me is how such an apparently simple thing doesn't seem to be catered for by the manufacturers of ventilation systems. Intermittent ventilation has its place besides DMEV and the like, when general airtightness is already too poor to warrant anything else.

Don't forget, "all boats float on a rising tide". except for those anchored to the seafloor