ᐅ Single-Wall Masonry vs. Cavity Wall with External Thermal Insulation Composite System (ETICS)
Created on: 3 Jul 2011 22:01
W
Wallace
I am planning to build a KfW70 semi-detached house with an air-source heat pump.
I can choose between the following two options:
- 36.5 cm (14.4 inches) masonry made of aerated concrete or Poroton brick
- 17.5 cm (6.9 inches) Ytong / hollow brick plus 10–12 cm (4–5 inches) external insulation system
What do you see as the advantages and disadvantages? The necessary insulation should be achieved with both systems. An energy demand calculation will be done beforehand, and KfW70 certification is guaranteed.
I think the second option has the advantage of thinner walls (7–9 cm (3–4 inches) more interior space), no risk of water freezing within the masonry (>0°C (32°F)), the masonry is exposed to smaller temperature fluctuations and is therefore better protected against deformation and cracks, and better sound insulation due to the external insulation system.
Disadvantages: the external insulation system is less resistant to mechanical stress.
Advantages of the 36.5 cm (14.4 inches) masonry: faster construction, greater thermal mass/volume resulting in a more comfortable indoor climate (temperature and humidity).
These are some assumptions I have made. What about the costs?
I can choose between the following two options:
- 36.5 cm (14.4 inches) masonry made of aerated concrete or Poroton brick
- 17.5 cm (6.9 inches) Ytong / hollow brick plus 10–12 cm (4–5 inches) external insulation system
What do you see as the advantages and disadvantages? The necessary insulation should be achieved with both systems. An energy demand calculation will be done beforehand, and KfW70 certification is guaranteed.
I think the second option has the advantage of thinner walls (7–9 cm (3–4 inches) more interior space), no risk of water freezing within the masonry (>0°C (32°F)), the masonry is exposed to smaller temperature fluctuations and is therefore better protected against deformation and cracks, and better sound insulation due to the external insulation system.
Disadvantages: the external insulation system is less resistant to mechanical stress.
Advantages of the 36.5 cm (14.4 inches) masonry: faster construction, greater thermal mass/volume resulting in a more comfortable indoor climate (temperature and humidity).
These are some assumptions I have made. What about the costs?
B
Bauexperte1 Sep 2012 17:44Hello,
Calcium silicate is a chemical compound belonging to the group of calcium compounds and silicates. Calcium silicate is used in the food industry as an anti-caking agent or as a carrier substance (for colorants and emulsifiers). It is approved in the EU as a food additive with the number E 552, with maximum limits of 10 grams per kilogram (4.5 oz per 2.2 lb) for certain foods, and for spices and dietary supplements without maximum limits.
Question answered?
Kind regards
bxka schrieb:I’m against hazardous waste
Now I’m curious whether the WDVS “skeptics” (Bauexperte especially don’t like EPS and other “plastic insulation”
bxka schrieb:Components: thermal insulation material made of calcium silicate hydrates, lime, sand, cement, water, pore formers (porosity > 95% by volume)
or if mineral insulation materials (e.g., Multipor) are considered “bad”....
Calcium silicate is a chemical compound belonging to the group of calcium compounds and silicates. Calcium silicate is used in the food industry as an anti-caking agent or as a carrier substance (for colorants and emulsifiers). It is approved in the EU as a food additive with the number E 552, with maximum limits of 10 grams per kilogram (4.5 oz per 2.2 lb) for certain foods, and for spices and dietary supplements without maximum limits.
Question answered?
Kind regards
The question of ETICS (External Thermal Insulation Composite Systems) versus single-layer or double-layer wall construction has been on my mind for some time. Homebuilding companies usually specialize in one preferred wall system. So far, I have consulted two specific companies and received different additional cost quotes for the following plans:
Building region Berlin/Brandenburg.
Provider 1:
Two-story townhouse, approximately 10.00 x 10.00 meters (33 x 33 feet) plus a single-story bay window 4.50 x 1.00 meters (15 x 3 feet).
Proposed wall construction: Aerated concrete 175 mm (7 inches) + 160 mm (6 inches) ETICS.
Additional costs for single-layer 365 mm (14 inches):
ThermoPlan MZ8 + approx. 14,000 euros (mineral wool roll)
Poroton T9-P 6 + approx. 13,000 euros (perlite insulation)
Poroton T8-MW + approx. 14,000 euros (mineral wool roll)
Ytong 0.09 + approx. 8,500 euros
Provider 2:
Two-story townhouse, approximately 10.50 x 10.50 meters (34 x 34 feet) plus a single-story bay window 4.00 x 1.00 meters (13 x 3 feet).
Proposed wall construction: Poroton T9 Plan (unfilled bricks), 365 mm (14 inches) + mineral plaster
Additional costs for filled bricks 365 mm (14 inches):
Poroton T9-MW (mineral wool roll) + approx. 7,000 euros
Poroton T8-MW (mineral wool roll) + approx. 10,000 euros
A well-known brick manufacturer:
Additional costs for filled bricks 365 mm (14 inches) compared to ETICS with 240 mm (9.5 inches) sand-lime bricks:
Poroton T9-P (perlite insulation) + approx. 3,500 euros (approx. + €15 per m² of exterior wall surface)
Poroton T8-MW (mineral wool) + approx. 2,600 euros (approx. + €11 per m² of exterior wall surface)
I will probably need to renegotiate, as the difference between the estimates from the well-known brick manufacturer and the construction companies seems too large.
Regards, o.s.
Building region Berlin/Brandenburg.
Provider 1:
Two-story townhouse, approximately 10.00 x 10.00 meters (33 x 33 feet) plus a single-story bay window 4.50 x 1.00 meters (15 x 3 feet).
Proposed wall construction: Aerated concrete 175 mm (7 inches) + 160 mm (6 inches) ETICS.
Additional costs for single-layer 365 mm (14 inches):
ThermoPlan MZ8 + approx. 14,000 euros (mineral wool roll)
Poroton T9-P 6 + approx. 13,000 euros (perlite insulation)
Poroton T8-MW + approx. 14,000 euros (mineral wool roll)
Ytong 0.09 + approx. 8,500 euros
Provider 2:
Two-story townhouse, approximately 10.50 x 10.50 meters (34 x 34 feet) plus a single-story bay window 4.00 x 1.00 meters (13 x 3 feet).
Proposed wall construction: Poroton T9 Plan (unfilled bricks), 365 mm (14 inches) + mineral plaster
Additional costs for filled bricks 365 mm (14 inches):
Poroton T9-MW (mineral wool roll) + approx. 7,000 euros
Poroton T8-MW (mineral wool roll) + approx. 10,000 euros
A well-known brick manufacturer:
Additional costs for filled bricks 365 mm (14 inches) compared to ETICS with 240 mm (9.5 inches) sand-lime bricks:
Poroton T9-P (perlite insulation) + approx. 3,500 euros (approx. + €15 per m² of exterior wall surface)
Poroton T8-MW (mineral wool) + approx. 2,600 euros (approx. + €11 per m² of exterior wall surface)
I will probably need to renegotiate, as the difference between the estimates from the well-known brick manufacturer and the construction companies seems too large.
Regards, o.s.
H
Häuslebauer407 Sep 2012 12:34What did you think the profit margins of a general contractor on materials are? 10%?
Häuslebauer40 schrieb:
What did you think the material margins of a general contractor (GC) were? 10%? Yes, exactly. I believe GC/general contractor markups of 10%, up to a maximum of 20%, are common and reasonable when it comes to individual projects. Turnkey construction may follow different rules, especially when there is no cost transparency on the client’s side. Hopefully, having more knowledge also creates a better basis for negotiation—that’s my hope...
Although I am not the original poster, I would like to share a few words on why I personally do not like ETICS (External Thermal Insulation Composite Systems) and why I am willing to spend several thousand euros more on a brick wall, even if it doesn’t insulate as well:
ETICS often (although not always) become dirty quickly, and when they do, it is in a very unattractive way.
This can happen as soon as 10 years, sometimes even sooner.
Frequently tilted windows, poorly insulated roller shutter boxes, nearby trees, and missing roof overhangs all promote even faster growth of algae, dust, and other deposits.
I live in the Berlin/Brandenburg area and could take hundreds of photos of typical ETICS dirt accumulation. Many of the new buildings and ETICS renovations are between 0 and 20 years old, and the pattern of soiling is so obvious that I am surprised this issue is not discussed more often here and in other forums as a disadvantage of ETICS.
Aside from the costs for repainting: I want to live in an attractive house, not feel ashamed in 10 years when guests come to the door...
By the way, it is completely understandable why most home builders add biocidal agents to render or leveling coatings—they can comfortably wait out the warranty period because the biocides delay soiling for several years before the substances are washed out.
Does anyone see this differently?
Best regards, Olaf
ETICS often (although not always) become dirty quickly, and when they do, it is in a very unattractive way.
This can happen as soon as 10 years, sometimes even sooner.
Frequently tilted windows, poorly insulated roller shutter boxes, nearby trees, and missing roof overhangs all promote even faster growth of algae, dust, and other deposits.
I live in the Berlin/Brandenburg area and could take hundreds of photos of typical ETICS dirt accumulation. Many of the new buildings and ETICS renovations are between 0 and 20 years old, and the pattern of soiling is so obvious that I am surprised this issue is not discussed more often here and in other forums as a disadvantage of ETICS.
Aside from the costs for repainting: I want to live in an attractive house, not feel ashamed in 10 years when guests come to the door...
By the way, it is completely understandable why most home builders add biocidal agents to render or leveling coatings—they can comfortably wait out the warranty period because the biocides delay soiling for several years before the substances are washed out.
Does anyone see this differently?
Best regards, Olaf
H
Häuslebauer407 Sep 2012 14:19o.s. schrieb:
Yes, exactly, I believe general contractor (GC) fees or overhead charges of 10%, up to a maximum of 20%, are common and reasonable when it comes to individual projects. Turnkey construction may follow different rules, especially if there is a lack of cost transparency on the client’s side. Hopefully, more knowledge also creates a better basis for negotiation – that’s my hope…You can safely forget the idea of 10 or 20%. 50% and above is more realistic.
More knowledge obviously provides a better starting point for negotiations, although it is often not very effective. Most general contractors are tough negotiators when it comes to price discussions and rarely make concessions, even when confronted with their often excessive, in my opinion, profit margins.
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