Foundation detail

[James13]

Hello All

 

I know this topic comes up a fair bit. Could someone tell me what the best material would be to use on the circled area? I am using the Jetfloor system -

 

Foamglas is coming in really expensive & Fonterra (jet floor) are telling me to use an Aircrete block.

 

The timber frame will sit on this.

 

Cheers

James

[warby]

Enter "Foamglas" into the search facility on the old ebuild forum http://www.ebuild.co.uk/ and you get plenty of information.

[TerryE]

We had to use this as thermal break on our stone skin (the details are really a separate post, but this was all OKed by the MBC structural engineer). Here is where we sourced ours: Phstore - Foamglas Perinsul HL.

[James13]

With a compression strength of 2.9 compared to that of 7.3KN of the aircrete block - will this cause a problem - Also as that block will need to be 150mm (140 Foamglas +10mm bed) Foamdglas is pretty expensive (extra 2400 pounds than I budgeted for this part of the build). Is this the way forward you believe?

[NSS]

James, I don't believe you need to fill all that 150mm depth with perinsul. We have a similar arrangement but used a coursing brick over the Perinsul. You can see it here http://strawberrytreelodge.blogspot.co.uk/2015/08/stage-2-blockwork-drainage-perinsul-and.html?m= 

[ToughButterCup]

@NSS, that was an interesting set of photos.

Interesting because I'm working hard at visualising our foundations. The mist is clearing only slowly, and photos help the most.

[James13]

@nss - are you putting a timber frame on this? - I assume its ok with the strength of 2.3KN? 

 - I am a few weeks behind you!

 

 

[James13]

@nss you have the same detail I am looking for - the insulation in your cavity is this 50mm? and did you just go around any air ventilation blocks?

[NSS]

Yes James, those pics were last September. Detail was all approved by SE, BCO and Scandia Hus before timber frame was erected.

Edited July 27, 2016 by NSS
typo

[NSS]

  On 27/07/2016 at 18:34, James13 said:

@nss you have the same detail I am looking for - the insulation in your cavity is this 50mm? and did you just go around any air ventilation blocks?

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We added 40mm foamglass in the cavity from just below the Perinsul to level with DPC and cut around the telescopic vents.

Edited July 27, 2016 by NSS

[James13]

  On 27/07/2016 at 18:38, NSS said:

 

We added 40mm foamglass in the cavity from just below the Perinsul to level with DPC and cut around the telescopic vents.

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This is what I was planning on doing, and this does not matter about filling that cavity do you not think?

[NSS]

Hi James, although the diagram on my blog shows 50mm foamglass in the cavity  (ie full fill through that section), we reduced it 40mm because the Scandia Hus wall panels have 'skirt' of the breather membrane that we have tucked in between the foamglass and the outer brickwork. This means any condensation that runs down the breather will find it's way into the void below rather than sitting above the insulation. I'm not sure I have any pics of this detail but will have a look tomorrow and post here if I find anything useful.

[NSS]

Sorry James, it seems I didn't take any pics showing the foamglass in the cavity. Let me know if I can provide any further detail though.

[Nickfromwales]

  On 27/07/2016 at 17:59, NSS said:

James, I don't believe you need to fill all that 150mm depth with perinsul. We have a similar arrangement but used a coursing brick over the Perinsul. You can see it here http://strawberrytreelodge.blogspot.co.uk/2015/08/stage-2-blockwork-drainage-perinsul-and.html?m= 

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Ahhh, 'tis true. A picture speaks a thousand words.   

[James13]

Thanks @NSS - really helps chatting to people who have been through it. The self builders assume much more knowledge of different products than house builders who do it then same way time after time!