Home DIY

To use lower temperatures (which are more efficient) you need a higher flow rate. Narrower than 15mm pipes won't provide enough flow, and even 15mm pipes won't be wide enough in some systems. Although the perception that ASHP means you need big wide pipes isn't necessarily right.

55° is the maximum flow temp in the new building regs (part L) but to get maximum efficiency you want 45°.

We're putting underfloor everywhere and installing lots of insulation so we can just swap in an ASHP in future (I think they're probably too noisy for us right now). As part of that I reckon we'll have at least 22mm pipes to the manifolds, although I haven't confirmed that detail yet.

Tumble dryers also eat your clothes, they are bad.
Still wouldn't mind one for drying down stuff.

gotcha

Thanks for that. I will give the Which app a look.

Oh also if you want to be compliant with the new regs/as efficient as possible pipe insulation is also now required. But a no brainer if you can do it fairly easily anyway I'd say.

yeah we're going to insulate all the pipes, they're all under floors so easy enough to access.

The loft has been converted to a spare room/office that gets daily use. Has a large window over dormer plus 3x Velux on same side as eaves.

Speaking as a parent I fucking love ours. It is invaluable.

I keep meaning to check how much electricity it uses/costs to compare with a more modern unit. However, at £30 + £25 for a new element over 4yrs. It would need to use a lot to justify replacing. Plus the synthetics cycle is pretty quick and my understanding is modern ones take half a day or something ridiculous.

And are there any easy DIY solutions for boarding over the brickwork or should I just make do with plugging the gaps?

It's a sliding scale of effort, cost and benefit.

Right at the bottom Imo is grabbing a load of that foil insulation stuff for sheds. It'd block the holes, just needs scissors and something to stick it down. It will also fit in your boot/under your arm vs massive sheets of something.

The next step up would be foam the holes, batons for an air gap, then glue insulated boards of some kind to the batons and foil tape to finish.

Tbh it might be worth adding batons even if you just do the foil as right now it's clear and empty so you'll never have a chance like this. Even with a hand saw and combi drill it shouldn't take too long to put a few vertical batons up.

Imo the main effort of that job will be getting everything you need up there through your house and whatever access into the loft. So minimising that is the best way to reduce the effort.

https://amzn.eu/d/6JHCkuc
(the link is just to explain what I mean there's probably better value stuff)

I got a washing machine with a dryer built in. Use it for drying small stuff like underwear but for everything else hanging it up in a room with a dehumidifier works better.

Trying to picture the setup here, but my very unexperienced view would be not to insulate anything other than the "walls" or sides of the the converted room which is sounds like has been done. If you're just storing boxes you don't particularly need to keep it warm and if everywhere else is insulated enough the cold roof space should not transfer cold air into the warm roof space. If you can see daylight through things thats not ideal so plug that up with something.

I have a similar-ish ish situation where we have rooms in the loft and on getting advice from insulation companies they have said not to insulate the roof space unless being used. So I am better insulating the sides/above of the rooms that sit in the loft and adding insulation between joist below to keep the warm air downstairs.

Now, all that may be nonsense but that was my plan and would be my approach.

I have been doing tours of houses with ASHP to help decide on which one’s best for us. Noise is a big concern.

I’ve looked at several Mitsubishi Ecodan, Daikin, Samsung and Vaillant units. The units with by far the quietest and least offensive sonic profile (frequency & harmonics) are the 5/7kW Vaillant models.

Everything else is noticeably louder and harsher-sounding, especially the two Ecodan units I heard.

We’re getting a 7kW Vaillant, which doesn’t sound too dissimilar to a boiler exhaust flue.

Oooh, good to know, thanks. How did you get the tours? Just mates or something more organised?

Ah, sorry, I meant can the remaining loft above your loft conversion still access the outside world without going via the eaves storage space?

But perhaps it's immediately the ~25mm cavity below your roof felt which joins the eaves storage space? Essentially you need to allow the outside world to get to the cavity beneath your roof felt in some form, so making the eaves storage space more airtight might not be the best approach unless the roof is already separately vented to the cavity underneath and doesn't rely on the eaves at all.

I think the best location if we got one would be in one corner of the garden with an insulated pipe. But any noise in the gardens around us echoes off the houses which have nearly all had loft extensions, it's like a canyon. It's a super quiet area (which is one of the reasons we moved here) and I don't want to be that guy...

@ectoplasmosis

bastard neighbours thread

Thanks everyone! On the basis that a small hole in the wall doesn't look like a deliberate ventilation tactic, I'm inclined to plug it in, then fit a draught excluder to the bottom of the eaves door into the loft room, and leave it at that.

I want to buy a joist and house hanger today. Whilst at the building supplies place someone I know to be a competent builder suggested what the store staff had recommended wasn’t going to be sufficient.

He suggested a thicker joist and to put it into the wall rather than a hanger.

My question is if I take out some brick to put the joist into and cement what if the beam isn’t the right height to support the beam. Is there anything I can put into the hole to pad it out?

Layers of slate roofing tile used to be the de facto shim.

A couple of mates, and a few more clients of the heating engineer who's going to be installing ours. All have been very accommodating and up for sharing real-world experiences of ASHPs in Victorian solid brick houses with varying degrees of retrofitted insulation etc.

I would deffo find a way to experience a Vaillant unit IRL if I were you. I was surprised at how they sound compared to other manufacturers. Like I say, it's not too dissimilar to an average gas boiler flue in terms of sound power and tonal quality.

Our cold water in pipe runs under the floor, up through by the kitchen sink where it has a stop tap then splits to go to the sink and also back down under the floor to then follow a wall up to the bathroom above. The hot in pipe does the same except coming from the boiler in the garage then up through the kitchen floor under the sink with a tap. We're moving some stuff around, is it crazy to think we should split the pipes while under the kitchen floor for the leg that goes up the bathroom before they reach the stop taps? The upside would be only 1 pipe coming up through the floor for each rather than 1 up and 1 back down for each, the downside would be no stop taps for the pipes that go up to the bathroom

did your builders advise on fibre board to use etc or have you specced it all out yourself?

Specced it all based on seshing PDFs and Buildhub forum.

Ordered these hangers yesterday afternoon from https://www.tcfixings.co.uk/home and by some miracle Royal Mail got them here this morning.

I couldn’t recommend this company enough

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