Aerated blocks, what You think?

Handsandtools

I find out, that some Aerated blocks used in Scandinavia and North Europe can achieve u-value of 0.17 W/K m2 without any extra insulation. They are 500mm wide. They also have 350 mm block with u-value 0.22W/Km2 without insulation.
Anyone have experience or any advice on this?
I know in UK aerated block becoming popular, not sure why in Ireland they are not, is there any obvious reason?

declan52

I used them in my build. They are approx twice the price of standard block and are far easier to lift and move about. They dont cut just as well with a bolster though.

Handsandtools

declan52 wrote: »

I used them in my build. They are approx twice the price of standard block and are far easier to lift and move about. They dont cut just as well with a bolster though.

You right about price, but savings are made by eliminate insulation and labor costs on that.
What about cut with a band saw?

kingchess

quinnlite and ytong blocks are very easy to cut with an ordinary( timber) saw.I used the quinnlite blocks as the internal leaf in my own house,they were the same size as the the standard concrete block used on the outside leaf.you need a bandsaw to cut poreton and other clay based blocks.

Handsandtools

kingchess wrote: »

quinnlite and ytong blocks are very easy to cut with an ordinary( timber) saw.I used the quinnlite blocks as the internal leaf in my own house,they were the same size as the the standard concrete block used on the outside leaf.you need a bandsaw to cut poreton and other clay based blocks.

I know about quinnlite, but these blocks are 350-500mm tick, so no cavity wall and no insulation, dimensions are 200 x 600 x 350/500 and have to use special adhesive not mortar.

kingchess

a buddy of mine is building a house with ytong ,I am not sure of the size but they are longer than a standard block and may be 350mm wide??he intends to put insulation outside these and then a standard block for outside leaf,he glued the ytong together with a thin bed joint and has wall ties that are screwed in to the ytong and these can be bent up or down as needed to meet the standard block,

Markcheese

I know there's no right or wrong really but does using aerated blocks as the inner leaf not just deprive the house of thermal mass ?
Would a thick cavity not be more effective ?

kingchess

thermal mass I dont know much about,the reason I used quinnlite in my own build was to keep heat in ,as these are around 10 times more insulating than an ordinary concrete block(which has very little insulating qualities anyway).

Admldj

Seen these being used on a site in sweden, unbelievable blocks! They're cut with a band saw and they are t & g so no mortar, there was an adhesive and a metal ladder track that went into the top groove, two brickies working it layed down easily 500 blocks in the day and were the cleanest brickies I have ever seen! by the next day the wall was set and was as strong as any i've ever come across.

Handsandtools

Admldj wrote: »

Seen these being used on a site in sweden, unbelievable blocks! They're cut with a band saw and they are t & g so no mortar, there was an adhesive and a metal ladder track that went into the top groove, two brickies working it layed down easily 5000 blocks in the day and were the cleanest brickies I have ever seen! by the next day the wall was set and was as strong as any i've ever come across.

I believe 500 a day?

Handsandtools

Markcheese wrote: »

I know there's no right or wrong really but does using aerated blocks as the inner leaf not just deprive the house of thermal mass ?
Would a thick cavity not be more effective ?

But insualting concrete blocks from inside will do it as well. I believe the best solution for that is to build a internal partition from concrete blocks or stone and use it as a heat accumulator.

Handsandtools

Quinnlite thermal characteristics are low and meet UK standards but for Ireland You need more insulation and better quality to meet standards.

BryanF

Handsandtools wrote: »

1. I find out, that some Aerated blocks used in Scandinavia and North Europe can achieve u-value of 0.17 W/K m2 without any extra insulation. They are 500mm wide. They also have 350 mm block with u-value 0.22W/Km2 without insulation.
2. Anyone have experience or any advice on this?
3. I know in UK aerated block becoming popular, not sure why in Ireland they are not, is there any obvious reason?

1. is this the crowd your referring to?
2. yes

3. Thermal conductivity depends on density, moisture content and ingredients of the material... As thermal conductivity is largely a function of density, it does not really matter whether the product is moist cured or autoclaved as far as thermal conductivity is concerned. The amount of pores and their distribution are also critical for thermal insulation .. Finer the pores better the insulation. As the thermal conductivity is influenced by the moisture content ... it should not be reported in oven dry condition

   source

Curly Judge

Any problem if you lay Breton slabs on inner leaf of outside wall?

BryanF

Markcheese wrote: »

1. I know there's no right or wrong really but
2. does using aerated blocks as the inner leaf not just deprive the house of thermal mass ?
3. Would a thick cavity not be more effective ?

[]

Handsandtools wrote: »

4. But insualting concrete blocks from inside will do it as well.
[5]I believe the best solution for that is to build a internal partition from concrete blocks or stone and use it as a heat accumulator.

1. a right or wrong in physics? :eek:
2. thermal mass still works with aerated blocks, just maybe not as well as will traditional blocks. but still better than say dry-lining
3. cavity? are we still talking about thermal mass? is the cavity sealed?
4. please explain? why would you do that?
5. would the aerated block walls not do?

BryanF

Curly Judge wrote: »

Any problem if you lay Breton slabs on inner leaf of outside wall?

your structural Eng will have a solution

kingchess

still 10 times more insulating than using a concrete block as an inside leaf,I put 80mm insulation in the cavity as well and my house is very warm and easy to heat,I have two fireplaces that I have never lit .sorry that I built fireplaces in .if I was building again today I would use the 8 inch wide quinn lite as an inside leaf. do you intend to plaster on to the thermal blocks as an outside finish?I would be worried about lateral stability-a strong wind blowing them in(probably totally mistaken).anyway I think it is a good idea,it will cost more but the added cost compare to standard block will be very small compared to the overall cost of the build.

BryanF

kingchess wrote: »

still 10 times more insulating than using a concrete block as an inside leaf

that's a bit of an exaggeration, don't you think?

,I put 80mm insulation in the cavity as well and my house is very warm and easy to heat

so lets say with 80mm insulation in cavity and with high density standard blocks on the inner leaf you get a result of around 0.35w/m2k. what do you think you'll get if you have aerated blocks on the inner leaf?

kingchess

cant be bothered digging out the specs for the quinnlite block but if memory serves me right it is 10 times more insulating than a standard block,as for your second question I dont know.

kingchess

ok,quinnlite b7 is 0.19w/mk. standard block is what??

BryanF

kingchess wrote: »

cant be bothered digging out the specs for the quinnlite block but if memory serves me right it is 10 times more insulating than a standard block,as for your second question I dont know.

thermal conductivity w/mk (which is what you are talking about)
u-value w/m2k (which is what i asked you about)
insulation terminology (what you & I are confusing)

kingchess

from the quinnlite pages it gives example of render,dense block,cavity,60mm insulation, b5 quinnlite,plaster-working from outside to inside-gives an u-value of 0.24w/m2k.now I used 80mm insulation and the b5 quinnlite so should have better u -value?

Handsandtools

BryanF wrote: »

[]
[/LIST]

1. a right or wrong in physics? :eek:
2. thermal mass still works with aerated blocks, just maybe not as well as will traditional blocks. but still better than say dry-lining
3. cavity? are we still talking about thermal mass? is the cavity sealed?
4. please explain? why would you do that?
5. would the aerated block walls not do?

Aerated blocks will do, but for better results as used in fireplaces ( not in Ireland) clay or stone will accumulate more heat.
Thermal mass works for every material, but if You look for material with low thermal conductivity You can't expect to get high thermal mass out of it.
U-values for these blocks are measured in normal working conditions, including cold bridging etc., not 100% dry.
Houses built from aerated blocks normally uses more energy to heat in first year, because they need time to dry, but after a first year they are dry and are up to the full potential.
There's different types of them: Hard blocks, universal, light and ecoTerm, different strength and thermal conductivity for different structures and needs.

Handsandtools

kingchess wrote: »

from the quinnlite pages it gives example of render,dense block,cavity,60mm insulation, b5 quinnlite,plaster-working from outside to inside-gives an u-value of 0.24w/m2k.now I used 80mm insulation and the b7 quinnlite so should have better u -value?

The U-value for walls 0.24W/Km2 are UK requirement, but in Ireland it is 0.21W/Km2 .
What was the price for quinnlite+ insulation?
I think costs are to high to get good value out of quinnlite, maybe I'm wrong.
I believe using one block instead of double block cavity, cavity insulation and insulation will cost less and reduces labor transportation and waste costs.
Tell me if I'm wrong!

kingchess

so-u-value of 0.17 for swedish type block with no extra insulation. u-value of 0.24 for quinnlite with insulation and standard block u-value of 0.35 for standard block with insulation and standard block.??? am I correct with these u-values?I built my house 7 years ago and the quinnlites were 1 euro 40 cent but i laid them myself.

Handsandtools

kingchess wrote: »

so-u-value of 0.17 for swedish type block with no extra insulation. u-value of 0.24 for quinnlite with insulation and standard block u-value of 0.35 for standard block with insulation and standard block.???

Yes that's what I'm talking about, taking to account that Ireland required U-value is 0.21w/Km2 and lower.
8.3blocks for m2 and strength is 1.8N/mm2.
Air tightness less than 1m3/m2h
That's what I find out.

Handsandtools

kingchess wrote: »

so-u-value of 0.17 for swedish type block with no extra insulation. u-value of 0.24 for quinnlite with insulation and standard block u-value of 0.35 for standard block with insulation and standard block.??? am I correct with these u-values?I built my house 7 years ago and the quinnlites were 1 euro 40 cent but i laid them myself.

Plus cost of insulation and labor for it.

kingchess

true,cant remember cost of insulation but cost of of quinnlite a1.40 a block=14euro/square metre,plus standard block on outside,I paid 2800 for the quinnlite blocks(did not do gables with them).I am blocklayer by trade so saved on that on labour.how much are your blocks per metre?.

BryanF

just to recap, as Handsandtools is asking one question a number of ways:

Handsandtools wrote: »

• They are 500mm wide.
• They also have 350 mm block with u-value 0.22W/Km2 without insulation.
• so no cavity wall and no insulation,
• dimensions are 200 x 600 x 350/500 and have to use special adhesive not mortar.
• U-values for these blocks are measured in normal working conditions, including cold bridging etc., not 100% dry.
• I believe using one block instead of double block cavity, cavity insulation and insulation will cost less and reduces labor transportation and waste costs.Tell me if I'm wrong!

will we ever see an aerated wall(no cavity wall and no insulation) with approval for the Irish climate?RH & weather conditions in Ireland are very different to those on the continent.


the idea of aerated walls (no cavity wall and no insulation) remaining dry in an Irish climate. consider weather proofing: absorption / adsorption leading to higher moisture content.



where I've seen this product used in Germany, Netherlands & UK, there was an outer brick face or some other element in the wall build-up -it didnt seem to be a 500mm aerated block wall only?



similar clay products like Poroton didn't really catch on here during the boom: are we brainwashed by the concrete federation? do we fear the big bad wolf blowing our house down? is a concrete home a better built home? are we just suckers for a good add campaign considering 4million + of our ancestors lived in cobs homes less than 100years ago? what are the co2 emissions for a 500mm aerated concrete block wall, when compared to say a 150mm aerated block with 150mm EPS out side it?

kingchess wrote: »

so-u-value of 0.17 for swedish type block with no extra insulation. u-value of 0.24 for quinnlite with insulation and standard block u-value of 0.35 for standard block with insulation and standard block.??? am I correct with these u-values?

please put in the values after your figures thanks. w/m2k or w/mk?

galwaytt

Handsandtools wrote: »

I believe using one block instead of double block cavity, cavity insulation and insulation will cost less and reduces labor transportation and waste costs.
Tell me if I'm wrong!

I won't tell you you're wrong, because you may not be: but as Bryan points out below, there is a reason why cavity construction (whether in masonry, timber, metal or other...) is standard here: it's to do with rain and dampness penetration here. That and the wind that drives it. The DoE here have a view that the cavity ensures that if the rainscreen is penetrated -through damage, age, shrinkage/other, that a cavity provides a second line of defence. In discussion with them myself a few years ago, and concscious that people often ask if they HAVE to have a cavity on our product, the Man in the DoE told me straight up that they would would have a difficulty with non-cavity building in this country due to 'wind driven rain'. The process to prove a single leaf system would work here has not been done, and the costs and time to do so would be huge. Easier to roll with the cavity......

Handsandtools wrote: »

Air tightness less than 1m3/m2h
That's what I find out.

Who's guaranteeing that airtightness ?

BryanF wrote: »

just to recap, as Handsandtools is asking one question a number of ways:

[/LIST]
will we ever see an aerated wall(no cavity wall and no insulation) with approval for the Irish climate?RH & weather conditions in Ireland are very different to those on the continent.


the idea of aerated walls (no cavity wall and no insulation) remaining dry in an Irish climate. consider weather proofing: absorption / adsorption leading to higher moisture content.



where I've seen this product used in Germany, Netherlands & UK, there was an outer brick face or some other element in the wall build-up -it didnt seem to be a 500mm aerated block wall only?



similar clay products like Poroton didn't really catch on here during the boom: are we brainwashed by the concrete federation? do we fear the big bad wolf blowing our house down? is a concrete home a better built home? are we just suckers for a good add campaign considering 4million + of our ancestors lived in cobs homes less than 100years ago? what are the co2 emissions for a 500mm aerated concrete block wall, when compared to say a 150mm aerated block with 150mm EPS out side it?



please put in the values after your figures thanks. w/m2k or w/mk?

^^^this ! :pac:

kingchess

w/m2k for u-values as quoted in my above posts,think they are correct.cavities seem to be important in our climate with our wind driven rain and humidity but then a lot of people are now filling cavities with pumped insulation -thus ending up with no cavites-so what does the DoE make of that ??(I have often worked on older block built houses where I had to open the outside leaf and the inside of that block was bone-dry so maybe wind driven rain is over stated)