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Good evening..

 

I have purchased an underground reservoir and am converting into a home. The walls are brick and concrete some 4 feet thick which is then covered in grass covered earth. My question is please who can give me advice about my hot water/heating requirements? I am reluctant to contact a local renewables firm who might just sell me their ASHP (as an example). I need impartial advice as to what will make the home efficient in terms of hot water, heating, MVHR. Can anyone shed some light as to where I need to start please? 

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Interesting project, where about  in the country is it?

 

Thermodynamics is fairly simple in principle.

Heat (which is the old word for energy) of itself, can only travel from the hotter to the colder.

 

It now gets into detail and silly terms.

But at this stage, no need to worry about that.

 

First thing to do is to measure all the wall, floor and room areas.  In metres.

Then note what they are made from and how thick they are, and which bits are are covered with earth.

From that, a U-Value of each element can be calculated and the expected weather/earth temperature seasonal profile established.  If the place is already weather proof, it may be worth getting/making a temperature logger.  Real data is really helpful.

Air changes an hour can be estimated (I suspect they may need to be a bit higher than normal).  Again, the calculation are pretty straight forward.

Domestic Hot Water (DHW) is usually around 80 litres per person, per day.  You may be able to estimate better than that from your current usage.

 

Where things start to get difficult is when you want to incorporate the effects of solar radiation, though if your house is basically underground that may be simplified, as will wind losses.

 

But first things first, measure the place up.

 

A read of this wikepedia page may be useful:

https://en.wikipedia.org/wiki/R-value_(insulation)

 

 

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quite a few of these sold off near me recently, went for crazy amounts

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would the spreadsheet @Jeremy Harris made to give you fabric losses be a start for your heating requirement

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What have you got access to is your first question, is there gas near your site for example??

Then you can work out your heat demand based on your build and your dhw needs based on how many people will live in your house. From them figures you can then work out what suits your circumstances the best.

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Excellent stuff thank you all.

20 hours ago, SteamyTea said:

Interesting project, where about  in the country is it?

But first things first, measure the place up.

 

A read of this wikepedia page may be useful:

https://en.wikipedia.org/wiki/R-value_(insulation)

 

 

 

The site is in Shropshire. I'll get measuring and reading.

8 hours ago, PeterStarck said:

@pepelepeu Hi and welcome to the forum. Sounds like a very interesting conversion much like one that was on Grand Designs recently. I guess you've seen it before.

 

https://www.granddesignsmagazine.com/grand-designs-houses/486-grand-designs-tv-house-2019-episode-4-hull

 

Good luck with the project.

 

 

yes saw this Peter. If you imagine a square I am intending to take out opposite ends for access and leave the rest as is which should result in a fairly airtight building.

 

5 hours ago, Oz07 said:

would the spreadsheet @Jeremy Harris made to give you fabric losses be a start for your heating requirement

ok I'll take a look.

 

4 hours ago, Declan52 said:

What have you got access to is your first question, is there gas near your site for example??

Then you can work out your heat demand based on your build and your dhw needs based on how many people will live in your house. From them figures you can then work out what suits your circumstances the best.

Hi Declan no gas it's very rural! I'm imagining all electric utilising ASHP...hence the request fo knowledge.

 

 

 

 

 

 

 

 

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