WHERE DO I START WITH HEATING OPTIONS

[Matt22]

Can anyone give me recommendations or suggest sites where I can find out information on what type of heating system I need as I'm CONFUSED.

 

I'm a first time self builder and navigating my way through all the information and decisions. We are building a 300sqm house (approx 177sqm downstairs and 130sqm upstairs) It's an upside down house with living upstairs and 4 bedrooms downstairs. 

We are planning to have underfloor heating in most spaces (radiators in bedrooms), 2 log burners and MVHR.

 

It's a rural location, no mains gas. The previous property used oil, we are knocking and re-buliding. We were planning to go LPG gas - but I'm told to meet SAP & EPC calculations we would need to put Solar panels in as well?

We've looked at ASHP but get really mixed messages on this. 

 

Any advice greatly welcome... (Thank you)

[ProDave]

This is a new build.  Take the chance to insulate it properly, detail it well to make it air tight, fit mvhr, so you will end up with a house that does not need much heat input.  Heat the whole house with UFH so it only needs to run at a low temperature, and then an ASHP will admirably heat the house well.

 

Fit solar PV as well and that will gain you SAP points and reduce your real running costs.

[Bitpipe]

So - what is your heat requirement based on your design (insulation and air tightness levels, solar gain, min external temp in winter)? There are some DIY models on this site to help you figure that out or more pro tools are available.

 

When you know this, you’ll understand what system will deliver an appropriate comfort level and what temp it needs to run at.

 

Mvhr will not make any meaningful heat contribution but will minimise heat loss through ventilation and suggests that your build is fairly airtight which means your heating requirement may already be lower than typical.

 

Log burners put out a lot of heat and you need to ensure they are sealed and do not compromise what you want your MVHR to contribute.

 

UFH in every area may need to run at a lower temp to avoid overheating. As you’re upside down that complicates the usual approach of concentring heating downstairs and  allowing convection to warm upstairs with bedrooms being cooler than living areas (which many prefer, including me).

 

Bottom line is you need to treat you house as a system that the heating is part of vs try and shoehorn something in without consideration to the environment it is in.

 

Needing to bolt things like PV on to get necessary SAP points is not really the best approach.

 

What’s putting you off ASHP?

[tonyshouse]

Add as much insulation as you can, draughtproofing and air seal entire structure, then look for places where more insulation could be added to good effect 

 

then design heating, if you still need it 

[Conor]

"meeting" SAP / EPC shouldn't be an issue for a new build as the standarda are so low compared what can be achieved easily with modern design and materials. You should be aiming for high levels of insualtion and airtightness, so the dependence on a heating system is much lower. And ASHP is the obvious choice. And question do you need to log burners in a highly insulated house.

[joe90]

Insulation, insulation, insulation, then airtightness. It’s all down to detail (which many builders don’t get yet). There is some bad press about ASHP but only when it’s not designed or installed properly. We have a small ASHP and it works well (and I installed it myself). Yes, we have a woodstove and love it, but many say a wood stove will over heat a passive house, we rarely light it as the house is a constant 21’ but lovely when we do. Our heating is only used about 3 months a year.

[Matt22]

9 hours ago, Bitpipe said:

So - what is your heat requirement based on your design (insulation and air tightness levels, solar gain, min external temp in winter)? There are some DIY models on this site to help you figure that out or more pro tools are available.

 

When you know this, you’ll understand what system will deliver an appropriate comfort level and what temp it needs to run at.

 

Mvhr will not make any meaningful heat contribution but will minimise heat loss through ventilation and suggests that your build is fairly airtight which means your heating requirement may already be lower than typical.

 

Log burners put out a lot of heat and you need to ensure they are sealed and do not compromise what you want your MVHR to contribute.

 

UFH in every area may need to run at a lower temp to avoid overheating. As you’re upside down that complicates the usual approach of concentring heating downstairs and  allowing convection to warm upstairs with bedrooms being cooler than living areas (which many prefer, including me).

 

Bottom line is you need to treat you house as a system that the heating is part of vs try and shoehorn something in without consideration to the environment it is in.

 

Needing to bolt things like PV on to get necessary SAP points is not really the best approach.

 

What’s putting you off ASHP?

Hi Bitpipe, 

Thanks for this a great help. I'll have a search around for some DIY models to help me understand the requirement.

 

Good point re bedrooms I prefer them to be cool - we were planning Radiators only in bedrooms and underfloor in each of the en-suites, hallways, office and utility downstairs.

 

We've heard mixed reviews re ASHP, considerations for us are cost to install / cost to run. one company told us that it's not there yet and we would be better having LPG and Solar panels to offset.

 

Thanks again 

Matt

 

 

[Matt22]

12 minutes ago, Conor said:

"meeting" SAP / EPC shouldn't be an issue for a new build as the standarda are so low compared what can be achieved easily with modern design and materials. You should be aiming for high levels of insualtion and airtightness, so the dependence on a heating system is much lower. And ASHP is the obvious choice. And question do you need to log burners in a highly insulated house.

Thanks. We are planning to go big on insulation.

 

Will look into ASHP more 

 

Good point re Log Burners - One is a key feature in the design more than for heat requirement - so think I need to balance that

[Conor]

13 minutes ago, Matt22 said:

Thanks. We are planning to go big on insulation.

 

Will look into ASHP more 

 

Good point re Log Burners - One is a key feature in the design more than for heat requirement - so think I need to balance that

I'd stick to the one feature stove . Good quality room sealed DEFRA approved stoves are not cheap, same for the flues etc.

 

 

Can't go wrong with lots of insulation, cold bridge detail, airtightness and MVHR.

[Bitpipe]

Start here - has link to the heat loss calculator.

 

Don’t be shy with questions !