Newbie to ashp - cost is scary!

[sirpatchuk]

@Radian you are talking me into it… just the worry! 
 

we also have these big patio doors which we didn’t plan on getting curtains for but guessing this is a big heat loss? It’s an east face garden.

 

[SteamyTea]

13 minutes ago, sirpatchuk said:

we didn’t plan on getting curtains

Get curtains.  While there may be some solar gain in the winter mornings, it is the colder side of the house, especially if an easterly blows in at night.

[sirpatchuk]

1 hour ago, Radian said:

 

You are quite right to be wary, but EPS beads are generally considered to be safe. Unlike fibre based products they don't wick water, don't compact over time and still allow a degree of airflow for drying out brickwork. Being spherical beads, they fill cavities very effectively with fewer injection holes. This makes them a good choice as the contractors that do the work are usually idiots - so an idiot proof system the best one to choose. Have a look at this energy saving trust document 

 

So a U-value of 0.14W/m²K  whereas your empty cavity walls lose nearly eighteen times as much heat.

@Radian

 

when I had a quote before they stated they would use Insta SuperBead.

 

Is that the same?

[Radian]

49 minutes ago, sirpatchuk said:

@Radian

 

when I had a quote before they stated they would use Insta SuperBead.

 

Is that the same?

 

SuperBead has a declared thermal conductivity of 0.033 W/mK which is exactly what I used to calculate your cavity wall loss after insulation (same as mine). They are graphite coated which makes them perform a little better than uncoated white beads. They say it's injected with a binder, which is good as it means the beads stay in position. Yes, they seem fine.

 

The installation company should send a surveyor to you first to establish the suitability of your property. If you decide on this, make sure you're present when the survey is done and sit on their shoulder - be nosey and ask questions. They should drill a hole in each elevation and put a borescope (camera) into the cavity to check its condition.

[SteamyTea]

31 minutes ago, Radian said:

They are graphite coated which makes them perform a little better than uncoated white beads

I know that graphite is anisotropic (better one way than the other) but the thermal conductivity, at best, is ~ 6 W/m.K.

Solid, non porous, polystyrene is around 0.15W/m.K. 

Expanded polystyrene is much better.

Now I know that the graphite coating is a few microns thick, so in reality, neither here nor there.

So what is going on?

Does it reduce moisture retention?

 

 

[Radian]

24 minutes ago, SteamyTea said:

So what is going on?

 

Good question. I've bee trying to figure out if it's a buffer to prevent plasticiser leaching, but all I could find was mention of it being used as a flame retardant. Probably came out as more insulating than uncoated within experimental error bars and got snatched-up by marketing. Dunno.

[SteamyTea]

1 minute ago, Radian said:

got snatched-up by marketing

Yes. I have two marketeers sitting behind me.

(expletive deleted)ing hell do they talk complete bollocks.

They are only good for colouring in charts.

[Radian]

3 hours ago, sirpatchuk said:

just the worry! 

 

I was sat on the fence for ages too. Then Vlad the Invader made up my mind for me. I researched the shit out of it and concluded it was the safest bet of all the competing systems. Being about one mile from the sea in exposure zone one, I wouldn't take any chances. Early days yet but no problems have shown up yet. And boy have we had some gales and driving rain since it was done!

[ReedRichards]

1 hour ago, SteamyTea said:

Now I know that the graphite coating is a few microns thick, so in reality, neither here nor there.

So what is going on?

 

 

Could the graphite be a lubricant, helping the polystyrene spheres fill the cavity rather than getting stuck somewhere and leaving some of the cavity unfilled?

[ADLIan]

Graphite in eps is an infra red blocker (absorber?) used to improve thermal performance.

Edited November 28, 2022 by ADLIan
Clarify blocker/absorber.

[SteamyTea]

21 minutes ago, ReedRichards said:

Could the graphite be a lubricant, helping the polystyrene spheres fill the cavity rather than getting stuck somewhere and leaving some of the cavity unfilled?

They may help flow by reducing the static electricity charge.  That would help in the 'packing'.

12 minutes ago, ADLIan said:

Graphite in eps is an infra red blocker (absorber?) used to improve thermal performance.

Interesting idea.

 

 

 

Edited November 28, 2022 by SteamyTea

[Radian]

It may well be all of the above. It's definitely been studied in use as a flame retardant but I've yet to see any studies on the other properties.

[HughF]

It’s highly likely that your Grant ashp has been installed with too many zones and on/off thermostats. The Grant (Chofu) controller is quite good, but grant decide to try and make it as easy to install as an oil boiler, so fit it with on/off controls that cripple the COP.

 

Ideally you’d have the WC setup for the rads, and a separate WC’d Esbe valve (with associated Esbe controller) on the UFH manifold.

 

Your UFH, did you say that was a spreader plate system? Any photo’s of how well (or badly) it was installed?

[sirpatchuk]

20 minutes ago, HughF said:

It’s highly likely that your Grant ashp has been installed with too many zones and on/off thermostats. The Grant (Chofu) controller is quite good, but grant decide to try and make it as easy to install as an oil boiler, so fit it with on/off controls that cripple the COP.

 

Ideally you’d have the WC setup for the rads, and a separate WC’d Esbe valve (with associated Esbe controller) on the UFH manifold.

 

Your UFH, did you say that was a spreader plate system? Any photo’s of how well (or badly) it was installed?

hi, this is probably the only photo I have which will give some idea 

 

 

[HughF]

Quality workmanship there 🤦‍♂️

[ProDave]

11 hours ago, sirpatchuk said:

hi, this is probably the only photo I have which will give some idea 

 

 

Yes sorry to say that is not good.

 

The ends are open to the cold under floor space, and that means the cold air can get between the spreader plates and the insulation.  Your insulation will be a lot less effective than it should be because of that and you will waste a lot of heat, lost to the under floor void.

 

We keep on about attention to detail being necessary for good performance, and that is sadly a good example of how performance has been degraded by a basic lack of understanding or just plain can't be bothered.  

[sirpatchuk]

32 minutes ago, ProDave said:

Yes sorry to say that is not good.

 

The ends are open to the cold under floor space, and that means the cold air can get between the spreader plates and the insulation.  Your insulation will be a lot less effective than it should be because of that and you will waste a lot of heat, lost to the under floor void.

 

We keep on about attention to detail being necessary for good performance, and that is sadly a good example of how performance has been degraded by a basic lack of understanding or just plain can't be bothered.  

 

To be fair that wasn't the best photo as the brick wall on the right was plaster boarded so I think / hope they filled in the other insulation.

 

More photos I have found.

 

[sirpatchuk]

[SteamyTea]

2 minutes ago, sirpatchuk said:

brick wall on the right was plaster boarded

So have they made a plasterboard tent inside our house?

[sirpatchuk]

On 28/11/2022 at 07:31, JohnMo said:

Just looking at the position where your pump is mounted does not seem to comply with Grants defined clearance requirements.  Which are, to the left 100mm that looks ok, but to the right they are looking for 600mm.  The issue you could have the heat pump is constantly recycling cold air which will affect the performance.

 

I would also make sure you don't have too many zones (areas with thermostats).

 

Did the installer, also install a buffer?

@JohnMo

 

Some more pictures.

 

I believe we have a buffer.

 

We have three zones downstairs - hallway, lounge, kitchen/diner

 

Each room upstairs is a zone.

It is getting downstairs to the required temperature is the issue.

 

[JohnMo]

Amazing how a photo can mislead you.  Looks good.

[PeterW]

With no cavity wall and the spacing on those pipes I’m surprised you’ve not got bigger bills ..! Get the insulation in, nothing you can do about spacing now. Also - is that filled with a pug mix or just spacers as the spacers shouldn’t be hanging down between the joists. Basically you need to get them tight up against the boards above, looking at that they are draped. 

[DundeeDancer]

23 hours ago, sirpatchuk said:

I think the reason is too many horry stories on retrospective cavity wall insulation with damp getting in the house.

It is 300mm rockwool in the loft

 

The modern cavity foam fillings are amazing, in your shoes I would be looking for a product like this:- https://isothane.com/products/technitherm/

The foam would be a complete barrier to dampness traveling across the cavity and the foam actually binds to the walls together making them stronger!

I wish someone would come and put the foam into my walls but finding an installer can be tricking depending where in the country you are.

Best of luck, DD 🙂

[JohnMo]

I would be careful going with anything closed cell.  If your tempted you would need an interstitial condensation study completed, prior to any payment or work commencing.

[sirpatchuk]

58 minutes ago, JohnMo said:

I would be careful going with anything closed cell.  If your tempted you would need an interstitial condensation study completed, prior to any payment or work commencing.

 

This is where I am going to get confused!  So @JohnMoare you saying 'no no' to https://isothane.com/products/technitherm/ but go with the Insta SuperBead....