silver bead insulation

cracked

hi,
considering using silver bead insulation in a new
build, would love some opinions on it vs. kingspan etc.

thanks

Retro-Fit

Neither kingspan nor Polybead deal with Thermal bridging. They dont perform to their quoted u-values and dont deal with moisture or heat modulation very well. It will proberbly take till 2011 before we realise how badly and innefficiently we have been building our houses in light of projected fuel costs and carbon pricing. For retrofit I'd externally insulate, id I had to dryline I'd use natural materials like woodfibre or sheepswool to handle interstitial condensation. For new build I'd use a 150 cavity, with cavity insulation air sealed before external wall built or preferably with a quinlite inner leaf. I'd consider a Structurally insulated wall panel (SIP). Don't build a min regs standard cavity wall with no airtightness, you'll regret it almost immediately. You'll never have a warm house.

cracked

man thanks for that ,
veering towards icf at the mo
only big issue is the cost difference(c30%)
probably worth it though.
cracked

Retro-Fit

ICF is the last thing you want, a sliver of cast concrete with half the insulation inside and half outside and nowhere for the concrete to dry out, full of cold bridges. Bulges like bubblegum, I thought you were building a wall?

cracked

footings under way at moment -they will allow for a 150 cavity if i go that route. not a fan of icf then?!! the icf guys talk a good fight with assurances of no bridging etc. have u good reason/experience to bring u to your opinion on icf?
thanks again for the feedback,
cracked

T-Square

whats cold bridges/bridging?

Carlow52

Retro-Fit wrote: »

ICF is the last thing you want, a sliver of cast concrete with half the insulation inside and half outside and nowhere for the concrete to dry out, full of cold bridges. Bulges like bubblegum, I thought you were building a wall?

Retro: I think the OP, and the industry deserve a little more than 3 or four off hand remarks listed above

Carlow52

T-Square wrote: »

whats cold bridges/bridging?

T Square: cold bridges/thermal bridges arise when there is a break in the insulation envelope in the building that allows heat/cold to travel in/out by 'bypassing the insulation envelope.

Take a simple example:
you build a solid block wall and over the windows and doors u use concrete lintels: say 9" wall with 9" lintels.

You then insulate both the inner and outer walls but dont do the inner or outer reveals on the heads of the doors and widows.

The cold will 'bypass the insulated walls via the uninsulated reveals.

Another example is in Alu framed windows and doors, u need a thermal break in the frame to 'break the frame and stop the cold passing through.
hope this helps

Retro-Fit

http://www.durisolbuild.com/
is a better type of ICF

For ICF to work you need to detail very carefully all junctions to eliminate thermal bridges or you will get water condensing on the areas where the internal insulation layer is reduced. Services are a pain, wiring and plumbing. Temporary shoring needed to keep walls plumb, and prevent blowout on 2 storey pours. The system is not diffusion open. It is difficult to fining or fix to. Finishes have a very sharp acrylic (american) look. The U-Values of 0.2 when 15% bridging considered become 0.23 (rising walls and windoe jambs + sills.

I'm not saying ICF is a bad product but you need a good contractor and architect to make sure its detailed right and built tight.

Carlow52

Retro-Fit wrote: »

http://www.durisolbuild.com/
is a better type of ICF

1: For ICF to work you need to detail very carefully all junctions to eliminate thermal bridges or you will get water condensing on the areas where the internal insulation layer is reduced.
2:Services are a pain, wiring and plumbing.
3:Temporary shoring needed to keep walls plumb, and prevent blowout on 2 storey pours.
3a:The system is not diffusion open.
4:It is difficult to fining or fix to.
5: Finishes have a very sharp acrylic (american) look.
6:The U-Values of 0.2 when 15% bridging considered become 0.23 (rising walls and windoe jambs + sills.

7: I'm not saying ICF is a bad product but

7a you need a good contractor and architect to make sure its detailed right and built tight.

Most of the above are not ICF specific so it is unfair.

I am not defending ICF but if there are issues they need to be ICF specific, especially for folks here that might get the impression that if they dont go ICF they will avoid these issues

[I inserted the numbers for ease of discussion.]

1: applies to all construction: for ICF much easier to get a fully insulated head and reveal than with trad build

2: not anymore than in a house with solid internal walls and concrete floors.

3: Most houses require scaffolding so the the extra is in aligning the ICF forms

blowouts only occur when someone has been careless in the setup.
I agree if u drop concrete into a ICF form from the apex of a 2 storey house a blowout is possible.

Much easier get very nice curves with ICF

3a dont know what you mean

4 Internally or externally I disagree as the ICF form-work is well capable of taking screws through the insulation, internally much stronger than dabbed drylining.

5: This applies to any render applied to external insulation.

6: not just ICF

7

7a applies to all builds.

Having said all that, the loss of internal thermal mass is one feature I don't like

cracked

so what route would you go?

Carlow52

cracked wrote: »

so what route would you go?

In order of preference:

1: What I call reverse ICF which is that the insulation is in the middle with concrete inside and outside: they are made in a factory and erected on site
AFAIK only 1 manufacturer in Republic.

2 ICF

either would have insulated foundations, well insulated concrete floors.

Both require a lot of planning for services such as wiring and plumbing so if herself decides half way through that they kitchen needs to be moved etc then its tough.

I prefer both of these as they get away from the cavity wall build on site disaster

If u are interested in ICF just call them up and ask to be shown a house being built: where in country are you based

cracked

food for thought!
many thanks,
cracked

cracked

Carlow52 wrote: »

In order of preference:

1: What I call reverse ICF which is that the insulation is in the middle with concrete inside and outside: they are made in a factory and erected on site
AFAIK only 1 manufacturer in Republic.

can u pm me any details so i can ckeck it out

Retro-Fit

Carlow52 wrote: »

3a dont know what you mean

Having said all that, the loss of internal thermal mass is one feature I don't like

The 2010 Part L requires all building to be of a low energy standard, less than 60% below the 2005 levels. We need to be building to that standard now, to head off energy prices, carbon tax and a house market that will be increasingly sensitive to building energy rating. Building Passive houses is a good stadard as unlike A rated houses, it focuses on building performance rather than just trying to balance energy in the building plans. ICF is a good stepping stone product in getting to low energy building, to its great credit it is simple and relativly robust, but it is not the system we will use in the next step. It is much better than the min standard cavity wall. there are some excellent ICF products out there like wolf, but ICF is not the product, that will build most of our low energy buildings in the next 5 years.

Vapour diffusion is critical for low energy builds to ensure moisture can vent through the wall fabric to the outside. Each hose produces 10L of vapour and a significant portion of this exits the buildings though the wall fabric.

Thermal mass is irrelevent in our climate. Concrete block does not offer thermal mass. CRH are selling a pup. 25mm of stone on a floor, or double layer of plasterboard offer thermal mass where they are exposed to a radient heat source such as the sun. Thermal inertia is more important. These are materials that can store heat slowly and release it slowly. EPS is good but natural materials like sheepswoll and woodfibre insulation are best. In roofs insulated on the slope with Polyiso, on hot days the heat getts through the insulation within 2 hours. Natural materials while you need more of them, regulate temperature and release this heat slowly over 8-12 hours to give a heat sourse for the cold nights that often folow sunny days.

ICF isn't bad, but for an ultra low energy house (why would you build anything less in our new age of scarcity) there are other options which perform better.

Carlow52

Jetro Fit:: you should go into politics.

I responded to your comments on ICF as I did not want the OP to be cracked up.

Dismissing CRH in 4 or 5 words puts you in a place i have no interest in going.