Heat loss and running cost

[CH1]

Very helpful thank you so much everyone!

[TerryE]

One of the side-effects of improving insulation is that it can have a significant impact on your heating design: we run our house as a single zone heated only by the ground-floor UFH in the slab.  The 1st floor doesn't need any heating at all, so we got no radiators, CH pipework, etc., no TMVs or zone control. But this can only work if the room-by-room heat balance keeps the rooms within a comfortable range, and that requires a minimum level of insulation.

 

We do have an issue with my son's bedsit in the 2nd floor (warm loft) which is prone to slight overheating in the hottest months (possibly thanks to his gaming PC being on when he is in the room) so we might need to install a local aircon option such as JSH described above, but this would still be the case if we dropped the insulation levels in the wall fabric and had 1st floor CH.

[dnb]

Very good example in the first post. But I think dogs are a very expensive method of heating Way more than direct electric! My boss makes a point of inviting guests most weekends to his house in winter. I think it must be to get free heating

 

I did a similar thougth experiment with my house design to prove the level of insulation it required to not need a conventional heating system. Of course, this means the house will most likely have an overheating problem when south-facing glazing is considered - hence the ducted air conditioning throughout. (It heats efficiently too.)  There's quite a saving in complexity by not having radiators, UFH etc, especially when you consider MVHR requires ducting anyway, and with proper sizing and design the A/C and MVHR can work together with virtually the same amount of ducting. 

 

The main driver for my build (300m^2) is indeed air tightness, and we are taking great pains to minimise this with the SIPS supplier - getting this right ought to give us another 3 months per year of no heat requirement.

 

 

[SteamyTea]

8 hours ago, dnb said:

to give us another 3 months per year of no heat requirement.

If I could do that, then I would not need any heating.

[coconutsaregood]

On 14/06/2016 at 17:55, Jeremy Harris said:

So, by doubling the insulation level we've decreased the heating cost by about 78%

Nice simple example but I shall inform others here that the Bldg Reg standards does reflect the whole problem taking into account all aspects of building and running costs. So following their redlines is a good bet in terms of a financial solution to the problem of insulating a building. If keeping your carbon footprint to an absolute minimum then yes the simple formula is a good one, but let us not get confused with mixing the two goals.

[TerryE]

On 26/04/2020 at 14:39, coconutsaregood said:

I shall inform others here that the Bldg Reg standards does reflect the whole problem taking into account all aspects of building and running costs. So following their redlines is a good bet in terms of a financial solution to the problem of insulating a building.

I've got an energy efficient house with a comparable but perhaps slightly lower spec than Jeremy's.  If you start with energy efficiency as a design goal then it doesn't cost that much extra than a normal BReg compliant build and there is a huge benefit in the quality of the lived in environment: air quality, total comfortable thermal environment, and the savings in running costs of course.  These costs were lost in the noise compared to some of the extras that or planners forced on us.

[jack]

On 26/04/2020 at 14:39, coconutsaregood said:

Nice simple example but I shall inform others here that the Bldg Reg standards does reflect the whole problem taking into account all aspects of building and running costs. So following their redlines is a good bet in terms of a financial solution to the problem of insulating a building. If keeping your carbon footprint to an absolute minimum then yes the simple formula is a good one, but let us not get confused with mixing the two goals.

 

A cynic would say that the building regs standards also reflect building industry pressure to allow them to continue building relatively low-spec boxes, even where that spec (and hence running costs) could be improved without too much extra build cost.