Hi all: Has anyone used the Isorast system? Or looked into it? It looks very interesting. Maybe cost prohibitive because of shipping? www.Isorast2000.com Thanks, -m

There is a house built with this stuff about 20 miles from me here in Shetland (off the north coast of Scotland). It is sold in the UK as Beco Wallform. The guy who has built his house with it is a professional contractor and seems happy enough with it. I have been looking at various ICF systems and my only concern about the Beco / Isorast system is that there are no fixing points for attaching things to it. I was talking to the contractor at the weekend and he said that he has started using timber battens on the interior walls. He covers the interior wall with building paper and then attaches the battens. The advantages that he sees with this are that it gives him a cavity between the polystyrene and the drywall so he doesn't need to use non-PVC cable or run the cables in conduit. He simply runs the services down the cavity. As far as external fixings are concerned, then anything of any weight needs to be fixed right through the polystyrene to the concrete so if you have four inches of polystyrene it all gets a bit tricky.

Thanks for the reply. Yes, it looked to me like there were no fastening surfaces embedded in the block like other ICF's. That may be a big disadvantage. I guess that's why they were pushing stucco (inside and outside) on the website. I suppose a batten system would work, but the walls would be REALLY thick..

-m

By the way, square meter of Isorast is about 68 euros, or around 100 USD.

WolfThermo has similar system with points, where you can screw in.

How do you know the pricing?? Don´t tell people something you can´t confirm

Hoowood, if I was going to use something like Isorast, then I would have a couple of questions. Firstly, wind driven rain is a major issue where I live. If I apply a decent render to the outside of the polystyrene, is that generally enough? Is there any recommendation to use water proof concrete the whole way up or anything like that? Secondly, I have concerns about fixing things to the outside of the building, particularly if I use something like the 375 or 438 systems to get a good U value. If I went for complete overkill and built a blockwork skin outside of the ICF wall, is there a recommended way of inserting wall ties to the Isorast system? Thanks for your help. AA

aa_uk

The concretre we are using is comparable to the psi 4500 im the US. Any siding could be used for the outsid but has almost no influence on the R-Value, because it is above R-70 and the dowels that we use are strong enough and available in all sizes. A waterproof concrete is always a good idea too at least on the weather side as we say here.

The passive homes that we build have a inner temperature of F70 without any heating system at all, thats hy we put the Airingsystem in that I have already promoted in my other threads.

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Rolf

aa_uk, I would advise you to use silicon based finish coating.

Hoowood, I can confirm.

However, if you can get me cheaper offer, please, do.

send me a list of what you need to [email protected] and I let you know. You want it shipped also? Need your location than too

Yes, I've built with it, and with the Beco blocks that are a UK copy.. I also built a brick skin with cavity using recycled bricks in a conservation area over a Bico block ICF shell.

Robin at Bico will tell you all about the various hangers and systems (in galv steel and in Stainless Steel) that you can use to fix stuff to the concrete core.

I highly recommend you call him!

If you're in N America I highly recommend QuadLock, which has built in fixing flanges.