Large listed property

[williamlincs]

Looking through the search results has yielded a bit of information but I’d just like to put a scenario to the forum to check whether intended direction to take with installation of DHW/Heating is what others would do, wisdom of crowds etc.

Have a very experienced installer on board

550 sqm listed house, 3 floors, stone walls, slate roof un insulated, single glazed sashes with internal shutters.

Heat loss calc showing requirements at 52Kw.

Solution would be LPG to do the grunt of heating in winter, with 2 x ASHP, the lot working in a cascade. 
no 3ph power and the quote to install is enormous, 100A supply.

This does rely on lifting the ground floor coverings, insulating and installing UFH, which isn’t going to be easy with all the old joinery.

Back of my mind is just fit an oil boiler, rads and be done with it, accepting the cost of insulating the property is colossal to do it properly, and whilst bills will be horrendous (circa 12k pa on oil), cost of remedial work/UFH is considerably higher. Can’t have solar due to surrounding buildings (also listed)

What would you do in this situation?

 

[Kelvin]

Cost to heat such a place will be horrendous no matter how you heat it. Sell it. 😂 

 

I’m inclined to agree and stick with oil and rads. 

[Gone West]

I also agree with oil and rads. Forget UFH and ASHPs but at the very least insulate the loft well.

[Jilly]

Congratulation, I love old houses, but maybe not in winter. Yes, you won’t get enough insulation under the floor and will have significant heat loss. 
The Period House Manual might be useful and the associated website to help you worry about preventing interstitial condensation. 
Back to Earth might be useful too.

I stayed in an old Georgian house which had beautifully made secondary glazing, not as efficient of course but better than nothing. 
Draught proofing will help hugely, but be mindful of causing damp.

Make use of solar gain if you can.

Thick curtains and jumper.
Thick, luxurious carpets will help. 
I’m not being facetious with these suggestions, but I think it is best to go with how the house would have been used by its previous occupants and improve on that. 
Or you could be a swallow, shut the house up and only live there in the summer and shoulder months. Buy a cheap place in the sun for the winter with the oil savings….

 

Edited June 20 by Jilly

[ToughButterCup]

11 hours ago, williamlincs said:

....

What would you do in this situation?

 

@Jilly's recipe is - from direct personal experience - excellent. Especially the thick curtains.

If there  an enormous fireplace, put curtains up on the lintel and sit inside the fireplace. Train children to fetch and carry stuff. Pre-heat your night clothes and put hot stones in the bed from late afternoon.

Ice makes beautiful patterns  on the inside of windows.

 

[williamlincs]

Thank you all. Had the blower door test yesterday, 2 fans, both on 90% couldn’t hold 50pa. The tester was walking around saying there is a door open somewhere.

Smoke in, fans in reverse, smoke piling out from the cellar. The old carpets are in, nice thick wool with underlay. Really quite remarkable how much ventilation the house has. 

 

[Oz07]

Oil and rads deffo. 

[MrPotts]

52kw heat loss is massive for a residential building, my house is a third of the size but 7 times less heat loss. Does the building have any historical importance?

[sharpener]

On 22/06/2024 at 10:36, MrPotts said:

52kw heat loss is massive for a residential building, my house is a third of the size but 7 times less heat loss.

 

I was wondering about that, 52kW over 550 sq m is about 95 W/sq m, spot on for the HG Cheat Sheet

 

 

We have a 192 sq m house with stone walls and slate roof that is only 62.5.

 

With 3 floors you should have a better surface area to volume ratio so I think the difference will be in the loft insulation and draught-proofing, can you do anything to improve those factors, yr air changes/hr must be horrendous?

 

100A will get you 23 kW(e) so about 69kW thermal from a HP so it is technically doable but the complicated cascade sounds something of a technical challenge!

 

UFH also not obligatory but you would need big rads instead to get a decent CoP. Not a problem with an oil boiler bc efficiency is not very dependent on flow temp. +1 for that as the solution.

 

Edited June 26 by sharpener