Keeping your home warm / heating / energy crisis / insulation etc

We're starting to get the ball rolling with external wall insulation considerations, getting recommendations for fitters etc, although we likely can't afford to get it done until next year it seems prudent to start to think and plan this year.

However, I'm in a bit of a rabbit hole of whether we should also be considering cavity wall insulation before...

The reasons I seem to be reading are a little confusing to me but sound like cavity wall (if left unfilled) can contribute to colder feeling due to cold outside air making its way into the cavity and would therefore make the EWI feel (or maybe be) less effective. I guess it would be like a warm jacket you put on but the wind going up the sleeves or something...

So, my question is. Does anyone have experience or opinon on whether it would be worth cavity plus EWI?

In the medium term cavity would at least make our house more comfortable, but long term is it just throwing money away if we will at some point look at EWI?

Filling your cavity walls with graphite EPS beads is (relatively) not that expensive, non-invasive and a no-brainer if your cavities are 100m+ deep. Do this first.

EWI would be great, but you may find that just doing the cavities will be sufficient.

Cavity walls are somewhat ventilated so yes, it would make sense that EWI would be undermined somewhat.

As above, CWI should be enough, EWI on top will be marginal. EWI is more aimed at older single skin buildings.

Nice, thanks!

Is there an alternative thread for 'keeping you house cool'?

Looking at ceiling fans and wondered if anyone had any experience with what to buy/look for?

Never had a ceiling fan, but reducing solar gain is top priority. Shade, solar-reflective window film, external blinds etc.

Or just fuck the dolphins and dash in a mini split AC; they’re cheap and very effective.

What makes ASHP good and mini-split bad?

They're the same thing.

I guess the point @ectoplasmosis is making is that it's ongoing energy cost rather than the reduced impact of shade, solar film or external shutters.

I can certainly highly recommend AC units but we have solar & battery so have very limited grid usage and even that's with Octopus so renewable.

As @Soul said, they’re both types of ASHP: one is air-to-water, the other is air-to-air.

Air-to-air units used for cooling are completely fine, but are frowned upon when used as a sledgehammer before tackling the primary causes of solar gain first, using passive methods as mentioned above.

This seems mad though and against my save the polar bear principles.

We're generally pretty good with using black out blinds to control solar gain and have double glazing on the top floor (4th floor standard victorian terrace with insulated loft).

Still gets to 30s pretty quickly on warm days and stays warm all night but a standing fan makes sleeping okay.

Internal blinds won’t do much to control solar gain; once the energy has got through the glazing and hits the blinds inside the thermal envelope, it’ll just keep heating up the air inside the room that then spreads all over the place via convection currents.

Solar film does work tho, even applied internally.

Internal blinds do make a huge difference. White on the outside will reflect a lot of IR back out, without them that energy will hit dark floors and heat the room up loads. Obvs not as good as shutters but much better than nothing.

Low-E glass blocks UV and bounces heat or cold back into the room.
Not experienced a hot summer here yet but had it fitted along with thermal blinds to help stop overheating with a huge south facing window. Might still buy a portable aircon unit if needed, I’ll know in a few months if that’s the case…

I guess if you have good insulation then you shouldn't need to run ac for that long to bring temps down.

Exterior over window shading is the way to reduce over heating (if allowed). It only shades during summer (when the sun is high in the sky), never needs to be opened/closed, is more efficient than an interior solution and costs less than treated glass.

I was wondering about this when is Aus. Everyone had aircon of course, but always just single glazing, even fancy new builds. There’s much more thought put into aspect and shading but seems like low hanging fruit. Would help with those savage 12 degree winters too.

I've got one in the bedroom and it's made summer sleeping bearable. Also great for drying laundry. Uses fuck all energy. My only wish was that the integrated light was dimmable (fancier models are) and that the slowest speed was even slower and quieter

Does anyone have any experience with Diathonite (or CorkSol) insulated render? Our upstairs bathroom is very poorly built but I don't want to go full EWI

A Maeco desk fan on low setting at entrance of bedroom blowing cooler air from a shaded hallway was a godsend in that 40° summer we had, not cheap but it was very quiet and I had it on while watching tv.
It was quiet enough to have on while sleeping.

So basically for non period properties and not for leasehold properties either. Would imagine there are not many situations where external shading was allowable or viable. I know we would not be allowed, we can’t even replace the single glazing.

We have the desk fan in the bedroom and is quiet enough on low to cool and not disturb sleep and the stand version for living room. Highly recommend both

I have a Meaco desk fan and Duux whisper pedestal fan.

Both very quiet so good to use when on calls whilst working or in the night when trying to sleep.

They come up on Amazon warehouse with a decent discount so worth setting an alert up.

We have 1 day of 17 degree weather and you guys are talking about air conditioning. Bloody English people.

I think mini-splits are often smaller units so are just inherently less effective

does anyone have a source for high BTU vertical rads?

These are probably the cheapest per BTU I can find (£325 for 10564)

https://www.designerradiatorsdirect.co.uk/reina-coneva-vertical