So many choices.. PV, SA, UVC, MVHR...

[Nickfromwales]

Yup. Worthy of its right place, that lot  

[Gone West]

21 hours ago, lizzie said:

I have investigated lots of external blinds (can give you company names but not recommends as not used the product) and may yet get a couple fitted next year but for me that is now a challenge as building is complete and cabling is a problem.  I think @vivienz is having external blinds and bris Soleil..

 

I am considering fitting these to my lift slide next year, don't know if you've seen them before.

https://solargaps.com/

[lizzie]

59 minutes ago, PeterStarck said:

I am considering fitting these to my lift slide next year, don't know if you've seen them before.

https://solargaps.com/

Thats a great idea, I searched for solar powered blinds and found nothing.  Will follow with interest, let us know how you get on.

[Alexphd1]

Maybe of a interest on the blinds is nobily (German site). I was going to use them for internal until I picked up a load of somfy  motors on fleebay.

[Nelliekins]

On 16/10/2018 at 11:11, Adam2 said:

Good to hear. We met with a local who is doing a Nudura build (just finished concrete pour on top floor) who is also enthusiastic.

Our architect and their often used (hesitant to say preferred) SE firm are pretty negative about ICF through lack of experience - for example their response back to the architect is below - nothing is probably actually 100% wrong (though I don't recognise some of the issues/terms used!) but indicates their view. Needless to say, I'm talking with other SEs that have ICF experience.

1. The main concern on this project would be the waterproofing system.  With an ICF product, how would the product be guaranteed?  Typically the crack widths would need to be no bigger than 0.2mm.  These are controlled by the amount of reinforcement and the cover to the reinforcement.  With ICF both the amount of rebar that can be incorporated with the wall and the cover tend to be fixed or difficult to change.  How would the walls be checked to make sure that 0.2mm crack widths have not been exceeded.
2. The house has a lot of large openings.  These could be difficult to prove using ICF due to the fixed width of wall.  There are only so many bars that can be placed within a certain width of wall.  This could mean that steel beams and or columns are required, causing further issues with detailing around the interfaces between the two.
3. Care needs to be taken when installing kitchen and bathroom units as the fixings need to be taken through the polystyrene and into the concrete.  The insulation could compress causing the units to be un level and out of alignment.
4. Detailing of structural elements can prove difficult trying to comply with the detailing code. 
5. The system is advertised as low level skill required to construct the system but in reality tying of rebar and pouring of concrete are skilled jobs and need skilled labour to carry them out.

 

 

Having nearly finished a Logix build under the occasional supervision of someone widely accepted as an ICF expert, I have a layperson's take on these... I am staggered an SE would mention any of this TBH!

 

1. Typically you would never inspect the poured ICF wall. Your SE should be engineering the steel in the walls to the point that crack widths become largely irrelevant except in relation to water penetration (which itself should be a non-issue). A good SE would realise that the concrete will be a LOT stronger than the stuff they make blocks out of (our mix came out at around C68 for the basement walls - 10× the compressive strength of dense concrete blocks).

 

As for waterproofing of ICF, tell them you will either go with a waterproof concrete (like we did), or simply render the outside of the house...

 

2. A 25mm diameter steel bar can take a LOT of load, and you can get 6+ into a 158mm ICF wall with little effort so long as you assemble the blocks around them... the biggest problem then is making sure that the concrete pour properly fills any voids between bars. 

 

Beyond that diameter you are getting out of the realms of rebar and into dedicated members (as they rightly point out), but then you benefit from not worrying about the pour filling voids between members, so it's swings and roundabouts.

 

Don't forget that (provided you have lifting gear on site) you can thread ICF blocks onto bigger horizontal steel members with the steel in midair. 

 

3. Forget about fixing kitchen cupboards to the ICF walls. Line the walls with either a double layer of Fermacell or a single layer of 18mm or thicker OSB/ply (screwed to the ICF webs) behind 15mm moisture resistant plasterboard. Either approach should be more than sufficient to hold up a few wall cupboards using e.g. 5x50mm wood screws. Why would an SE care how you hang cupboards - that's nothing to do with them?!?!

 

4. Uhm, surely that's the job of the architect and the SE? Is the SE seriously trying to dodge that?

 

5. I would expect the SE to produce drawings to show where to tie the rebar, and doing the tying really isn't a very skilled job. Clearly this SE hasn't been on any ICF build sites, or they would know how easy it is to tie rebar... I did nearly all of the lintels, including one over a set of 6m wide bifolds, on my own (and that included 4no. 25mm rebar, 7.2m long, with 35 H12 links around them, all set into 2 courses of Logix 6" blocks).

 

It's helped by knowing that typically links are placed either singly or in pairs per web spacing in the ICF blocks. If you want some photos and exemplar SE drawings to see how they marry up, I can provide them from my build.

 

As for pouring of concrete, I don't think it is massively skilled either. It's more about understanding the process. The bigger problem is obtaining enough bodies to help, because really you want 2 people moving the pump hose around, 1 person or more vibrating the concrete behind the pump hose (carefully so you don't damage the ICF blocks), one person indicating when each circuit of the pour has reached a suitable depth, and one person looking for blowouts and bulging.

 

I had helpers on each pour, because it's a 4-6 man job, not a 1-2 man job.

 

FWIW my first SE was worse than useless when it came to ICF construction... he was specifying steel that could never work within the limitations of the blocks. He wouldn't listen to me, so I took my ICF expert to talk to him. Wouldn't listen to the expert, so I had the ICF company phone and email as well. When he still refused to listen, we parted ways, and I found an SE with ICF experience. The difference was night and day. 8 weeks of grief with the first SE, and under 1 week turnaround with the second SE, plus plenty of phone and email assistance afterward.

 

Happy to recommend our SE though, via PM, if you can't find one you are happy with. Also, speak to the ICF firms - they will have a list of preferred SEs that they have a working relationship with. 

 

HTH.

 

Neil.

[Adam2]

Cheers Neil, good to read your reassuring comments which fit with my expectations. I have an SE with significant ICF experience so feel quite positive about the way forward. Would be interested to see any example SE drawings for your ICF. Logix is local to me and one of the shortlisted firms.

Thanks for the detailed response.

Adam