ᐅ Y-Tong vs. Concrete Without Additional Insulation in Practice (Heating Costs)
Created on: 28 Feb 2019 17:02
K
Keishadow
We are about to start building a house using Ytong blocks without additional insulation, with underfloor heating and a heat pump.
Nevertheless, I am interested in this comparison and roughly how much higher heating costs in percentage terms could be expected, if that can even be calculated.
Energy saving is a big focus nowadays. That’s why Ytong was recommended to us, suggesting that extra insulation might not be necessary. The walls can breathe, and the U-value is sufficient. However, the problem with the U-value is that it is a "laboratory value." In practical situations, the sun shines outside, even in winter! Materials with high density like concrete, calcium silicate blocks, etc., are warmed by the sun and can transfer that heat inside the house. Ytong heats up less strongly but retains the interior heat for longer. The same issue applies to triple-glazed windows. They keep the heat inside better but don’t allow the interior space to warm up as much when the sun shines. This puts the U-value into perspective and makes calculating the actual energy consumption for heating somewhat complicated.
If you also factor in air conditioning, which is used in summer to cool a Ytong house, it gets even more complex. Concrete, on the other hand, could keep the interior cooler in summer, potentially allowing one to avoid air conditioning altogether, which saves energy again.
So, it could well be that the difference in heating costs is not as significant as expected in the end. However, with concrete, you might enjoy significantly more comfortable temperatures during the summer.
Does anyone have experience with this? Perhaps someone lives in a concrete house without insulation and can share insights about the indoor climate and heating costs? I would be really interested to hear what comes out of it...
Nevertheless, I am interested in this comparison and roughly how much higher heating costs in percentage terms could be expected, if that can even be calculated.
Energy saving is a big focus nowadays. That’s why Ytong was recommended to us, suggesting that extra insulation might not be necessary. The walls can breathe, and the U-value is sufficient. However, the problem with the U-value is that it is a "laboratory value." In practical situations, the sun shines outside, even in winter! Materials with high density like concrete, calcium silicate blocks, etc., are warmed by the sun and can transfer that heat inside the house. Ytong heats up less strongly but retains the interior heat for longer. The same issue applies to triple-glazed windows. They keep the heat inside better but don’t allow the interior space to warm up as much when the sun shines. This puts the U-value into perspective and makes calculating the actual energy consumption for heating somewhat complicated.
If you also factor in air conditioning, which is used in summer to cool a Ytong house, it gets even more complex. Concrete, on the other hand, could keep the interior cooler in summer, potentially allowing one to avoid air conditioning altogether, which saves energy again.
So, it could well be that the difference in heating costs is not as significant as expected in the end. However, with concrete, you might enjoy significantly more comfortable temperatures during the summer.
Does anyone have experience with this? Perhaps someone lives in a concrete house without insulation and can share insights about the indoor climate and heating costs? I would be really interested to hear what comes out of it...
N
nordanney28 Feb 2019 20:37Keishadow schrieb:
Wall can breathe I just stayed completely quiet and tried to hear the wall breathing. Didn’t work.
Conclusion: walls don’t breathe.
Keishadow schrieb:
With concrete, the interior would stay cooler in summer ... but only as long as the heat hasn’t found its way inside yet. After that, you can’t get it out anymore – just like any other house. The walls simply store heat.
Keishadow schrieb:
That’s why we were also recommended Ytong Did they also mention any disadvantages? For example, regarding sound insulation?
The conclusion is that you can build a solid house using any kind of masonry. It can even be done without bricks or blocks (e.g., timber frame construction). Everything has its pros and cons, but it works.
BUT: concrete as a building material for houses is quite unusual. Insulation then definitely needs to be applied on the outside. Concrete walls also have other disadvantages.
M
Mottenhausen28 Feb 2019 21:38Caspar2020 schrieb:
where concrete can still be used without additional insulation; except in bunker construction.Even here, you can no longer do without insulation.
Seriously, plain concrete does not work—you might as well camp outside in winter. Or stay out in the sun without shade in summer.
K
Keishadow28 Feb 2019 23:53nordanney schrieb:
I just stayed completely quiet and tried to listen to the wall breathing. Didn’t work.
Conclusion: Walls don’t breathe. That’s called vapor-permeable. And yes, I understand soundproofing and all the other aspects. For example, windows let through more noise than aerated concrete blocks like Ytong. I have at least been inside such houses and know that the sound insulation to the outside is fully sufficient.
I was mainly interested in a practical example of a pure concrete bunker to learn about heating costs and living comfort, just to get real data out of pure interest—not the usual theory where every manufacturer, expert, or salesperson says something different and truly believes only their opinion is correct and everyone else has no clue. I know such buildings exist. Although I don’t know if there might be insulation installed on the inside. That’s why I’d like to understand why it was built that way. The builder must have had some reason. Because building like that is theoretically totally crazy... but how about in practice?
K
Keishadow1 Mar 2019 00:18Or are the exposed concrete houses perhaps built from lightweight concrete?
C
Caspar20201 Mar 2019 02:16
This resulted in a dense lightweight insulating concrete (LC 12/13) with a dry bulk density of 1,100 kg/m³ (69 lb/ft³), which was used as exposed concrete.
Expanded clay was used as the aggregate, providing additional thermal insulation that makes external insulation for the single-layer 50 cm (20 inches) thick wall unnecessary. Even with lightweight concrete without external thermal insulation composite systems (ETICS), you are dealing with very specific wall thicknesses.
Additionally, lightweight concrete with a density of 1,100 kg/m³ (69 lb/ft³) has a thermal conductivity (lambda) of about 0.40 W/m·K, whereas aerated concrete (e.g., Ytong) ranges from about 0.07 to 0.10 W/m·K.
That is a huge difference.
N
nordanney1 Mar 2019 07:58Keishadow schrieb:
So I would like to understand why it was built that way. The homeowner must have had some reason. Because building like this is totally crazy in theory... but in practice? 1. In practice, concrete is generally not used. These are usually unusual architect-designed houses or multi-family buildings made from prefabricated walls plus external insulation.
2. Since all new buildings today must comply with energy-saving regulations (building permit / planning permission), the difference in heating consumption is negligible for construction costs over €500,000 (about $540,000). Whether you use €20 more or less on heating is not decided by the house itself but by your heating and ventilation habits.
Similar topics