ᐅ Single-Family Home Energy Saving Regulation 2016: Is Additional Insulation Recommended by Developers Worthwhile?

My goodness, you’re really bad at this... I just wanted to tell the original poster that they don’t need to worry if they decide against the additional costs—the house will still be very energy-efficient.

Sorry, the annoyed tone of the original poster upset me in a similar way.
And apparently, I was a bit slow on the uptake... but now I understand! Thanks for your patience.

And I believe that if you build "only" according to the 2016 Energy Saving Ordinance, it can still be energy-efficient AND economical. It could surely be more economical... but unfortunately, I haven't been able to figure out how!

BeHaElJa schrieb:
I just wanted to tell the original poster that they don’t need to worry if they decide against the additional costs – the house will still be very energy-efficient.

... that’s kind of you – that’s also how I understood you. The problem is that the extra costs are unavoidable if I want a gas condensing boiler. In my payback calculation, I have to consider these extra costs separately because the additional insulation might pay for itself over time.

@Manu1976
The advantages of monolithic construction are obvious. You could also have mentioned the issue of attaching external fixtures (canopies, lights, awnings, etc.). As I said, we considered it too, but it’s not just 10cm (5 inches) less space in the children’s room. Overall, it’s almost 10m² (108 sq ft) less (comparing monolithic 42.5cm (17 inches) Poroton versus 17.5cm (7 inches) + 16cm (6 inches) EPS insulation).

Still, I would have appreciated getting a bit more information on roughly how many kWh I could save with the described additional insulation (just a rough estimate, of course).

Hi Ölschlamm,

What’s going on in this thread? There’s no need to argue...

ölschlamm schrieb:
Oh, thanks for the responses

@andimann: Your point ultimately makes sense (if the numbers are roughly correct). Based on my rough calculations, an air-to-water heat pump would use about 3000 kWh per year (an annual performance factor of 2.1 is realistic with panel radiators and a supply temperature of 45°C (113°F) – no discussion, that’s what I want! – and in a very drafty high-altitude location on the Swabian Jura at about 600 meters above sea level (1970 feet) – it won’t be better than that), so electricity costs around 750 euros. With the gas system, I’d probably use 6000 kWh minus 1500 kWh from solar thermal = 4500 kWh, so about 260 euros.
That roughly saves 500 euros per year but with additional costs of about 9000 euros (gas tank, connection, chimney, etc.).
Add another 100 euros savings through insulation, so 600 euros per year. Still probably not a good idea.

michael

Reading your data again, you’ve basically answered your own question about which heating system to use. Given the conditions (cold area and a heating system that requires a supply temperature of 45°C (113°F)), you can simply forget an air-to-water heat pump. It will deliver an annual performance factor that’s really poor (I consider your 2.1 realistic because, for large parts of the winter, it will operate purely as electric resistance heating via the boiler’s heating element). And that unit likely won’t last long.

Almost every electrical device (fridge, power drill, and drive systems) is designed for a certain switching frequency and run time per hour. A typical power drill, for example, is designed for a maximum of 5 minutes per hour.
Your air-to-water heat pump under these conditions will run at full load far more often than intended. Don’t expect it to last 15 years.

There are air-to-water heat pumps designed for different environmental conditions and higher supply temperatures (different refrigerants, pressures, etc.), but I’d expect those to be significantly more expensive.

If you choose a heat pump, you will most likely need a ground-source (geothermal) heat pump. That will almost certainly be more expensive than gas, including solar thermal, gas tank, and so on.

Also, your estimate of 6000 kWh heating demand is, at best, optimistic. In a warm residential location in Franconia at 360 meters (1180 feet) elevation, for 135 square meters (1450 square feet) with a wall U-value of 0.19 and triple-glazed windows, we calculate about 10,000 kWh heating demand (8500 kWh gas plus 1000-1500 kWh from solar thermal).

So better estimate at least 1000 euros per year in electricity costs for an air-to-water heat pump compared to 500 euros for gas.

In my view, your question isn’t "Is it worth investing more in insulation?" but rather "What do I have to do to get the building permit / planning permission with a gas heating system?"

Just two more questions:

Have you already signed a contract with your builder, or are you still negotiating? In other words, will the new Energy Saving Ordinance (effective from January 1, 2016) apply to you? Because with your parameters, you might have a problem there...

What do you have against insulating below the floor slab? That’s actually quite common and not unusual. According to several experts, it’s perfectly fine.

Best regards,

Andreas

Hello,

ölschlamm schrieb:
...that’s correct, but the payment is based on the living area in square meters, not the built-up area in square meters – so how much do 10 m² (108 ft²) of living area actually cost us?

I’m not sure how you arrived at minus 10 m² (minus 108 ft²), but for me, a 6 cm (2.4 inch) difference equals 2.40 m² (26 ft²) per floor in your example; so just under 5.00 m² (54 ft²) for the entire house. Anyway, you have made your decision.

Whether an increase in insulation will be beneficial depends on the calculations for the house; financially, in terms of heating cost savings, it may not pay off. However, it *might* be necessary to increase insulation in order to comply with the 2016 Energy Saving Ordinance if you plan to continue using gas as your heat generator.

Regards,
Bauexperte

Is there no alternative to the air-to-water heat pump besides gas?