pro's & cons of different ICF systems

[Jeremy Harris]

2 hours ago, jack said:

What about putting strips of something over the webs (or maybe every third of fourth web) that will be detectable with a stud-finder? Would aluminium tape work?

 

 

Aluminium tape works fine.  I ran lengths of it behind all our plastic pipe runs in the service void, so they show up on a pipe detector, and it seems to work OK when I've tested it with my el cheapo pipe/cable/stud locator.

[najem-icf]

7 hours ago, jack said:

To be fair, I don't think cement-impregnated wood is anywhere near as attractive to vermin as the sheepswool in that article.

Point I was trying to make is that regardless of how you treat an organic product, it will still eventually attract vermin...

 

7 hours ago, jack said:

As you referring to the internal PIR/PUR or a separate later added afterwards? If the former, as I understand it, if there's no gap between the foil and the next surface, the foil contributes nothing to the insulation value anyway, since it can no longer reflect radiated heat. Heat will instead move by conduction due to contact. In that case, it's irrelevant whether the foil is intact. 

Ah - no - that's not quite right sir.  The foil on the PUR/PIR boards is aluminium based, and it will burn off if in direct contact with concrete.  Fresh concrete corrodes aluminum with
subsequent release of hydrogen. After the chemical reaction, the concrete loses its properties and deteriorates. The concrete is no longer homogenous.  Significant testing has been done Stateside that confirms this.  This is before we even consider the reaction between concrete and PUR/PIR as well as Hydrogen - usually results in air bubbles in the concrete.  If those air bubbles form near rebar, you end up with corrosion.  There is a reason every single BBA for PUR/PIR foil faced boards say the same thing - cement must never come into contact with the foil - a polythene sheet must be placed between the foil and the concrete.

 

6 hours ago, JSHarris said:

The level of false information floating around about the foil on insulation board needs addressing.  There isn't an issue with pouring concrete on foil faced insulation.

I have an e-mail from Celotex and Kingspan that differ with your view that "there isn't an issue with pouring concrete on foil faced insulation."  I would much rather follow the BBA certificate and the manufacturers installation instructions sir.

 

7 hours ago, JSHarris said:

The foil, or often silver coloured paper, facing on some forms of rigid insulation is there for a few reasons.  It makes the material easier to handle in the final stages of manufacture, transport and handling on site, and it provides a partially effective radiant barrier when exposed to an air gap, where it can reflect back some of the long wavelength IR and so help to reduce surface heating of the insulation from heat radiating on to it.  This latter property can be useful in wall or roof construction, where reflecting back out excessive secondary solar radiation can help to improve the short decrement delay factor that all low heat capacity insulation materials have.

True - you are correct in the handling and reflection aspect, however it is also to keep gasses from escaping.  PUR/PIR off-gas.

 

3 hours ago, JimG said:

The other thing is that assuming I do this, locate a web and screw a fixing to it, how do I know how far from the centre of the web I am? Have I just caught the edge of it, giving enough resistance to feel good but not enough to be strong?

You could potentially face the same issue with any other method of construction - stick build - you could catch the end of the timber *only just* - or with masonry - you could be drilling into weak mortar.

 

3 hours ago, JimG said:

Do I worry too much? ;-)

IMHO - yup

 

2 hours ago, jack said:

What about putting strips of something over the webs (or maybe every third of fourth web) that will be detectable with a stud-finder? Would aluminium tape work?

Usually you will be able to feel or detect screws fixing the plasterboard back to the strips - use this as your datum...

 

Hope this helps - absolutely enjoying discussion like this - is that sad on my part?  

[Jeremy Harris]

6 minutes ago, najem-icf said:

True - you are correct in the handling and reflection aspect, however it is also to keep gasses from escaping.  PUR/PIR off-gas.

 

 

To be honest, I can't see how the silver painted paper covering that's on one side of Celotex PIR can in any way impede vapour or gas movement.  The stuff is clearly permeable, as you can see if you tear a bit off.  Also, the edges of the foam panels aren't sealed.  The final nail in the coffin for the prevention of off gassing idea is that if the foam was still off gassing and if the silver layer was impermeable, then the pressure build up would just blow the surface layer off and cause it to unbond.

Edited September 15, 2017 by JSHarris

[jack]

22 minutes ago, najem-icf said:

Point I was trying to make is that regardless of how you treat an organic product, it will still eventually attract vermin...

 

Taken to its end point I suppose that means you must object to all forms of wooden construction. I'm not sure it's fair to lump all forms of organic material in with untreated and/or poorly encapsulated sheepswool!

 

22 minutes ago, najem-icf said:

Ah - no - that's not quite right sir.  

 

You said "In essence, the concrete burns the foil and renders the board much less effective"),  To the extent that my answer addressed that statement, I believe it's correct. 

 

22 minutes ago, najem-icf said:

The foil on the PUR/PIR boards is aluminium based, and it will burn off if in direct contact with concrete.  Fresh concrete corrodes aluminum with subsequent release of hydrogen. After the chemical reaction, the concrete loses its properties and deteriorates. The concrete is no longer homogenous.  Significant testing has been done Stateside that confirms this.  This is before we even consider the reaction between concrete and PUR/PIR as well as Hydrogen - usually results in air bubbles in the concrete.  If those air bubbles form near rebar, you end up with corrosion.  There is a reason every single BBA for PUR/PIR foil faced boards say the same thing - cement must never come into contact with the foil - a polythene sheet must be placed between the foil and the concrete. 

 

I'd be interested to know how much hydrogen is generated and how deeply it potentially penetrates the concrete in a Durisol application. I suspect the risk is much higher in a flooring application, where the bubbles are formed underneath a layer of concrete, and could rise into it through buoyancy. In the Durisol application, the hydrogen bubbles would need to move horizontally into the concrete to cause trouble, based on their relative positions in a Durisol wall. Seems less likely than the flooring case.

 

Interesting to hear this though - I'd never really thought about the advice not to allow concrete into contact with foil-faced insulation. 

 

 

 

 

[najem-icf]

34 minutes ago, JSHarris said:

To be honest, I can't see how the silver painted paper covering that's on one side of Celotex PIR can in any way impede vapour or gas movement.  The stuff is clearly permeable, as you can see if you tear a bit off.  Also, the edges of the foam panels aren't sealed.  The final nail in the coffin for the prevention of off gassing idea is that if the foam was still off gassing and if the silver layer was impermeable, then the pressure build up would just blow the surface layer off and cause it to unbond.

 

Correct re edges not being sealed - precisely why the BBA Cert and manufacturers installation instructions state that foil tale must be used where two boards join.  Ask any builders merchant if they (a) stock it and/or (b) have sold any.  The answer is usually no to both.  Hence the poor quality of UK housing stock.

Edited September 15, 2017 by najem-icf

[najem-icf]

2 minutes ago, jack said:

Taken to its end point I suppose that means you must object to all forms of wooden construction. I'm not sure it's fair to lump all forms of organic material in with untreated and/or poorly encapsulated sheepswool!#

From what I read in the article, that stuff was treated.  I was a treehugger - but given that we are consuming more lumber than we are planting (http://www.globalforestwatch.org/) and the harm we are doing as we prepare timber for use in construction, as well as the damage to the environment caused by producing additional material sued in wood construction.

 

6 minutes ago, jack said:

You said "In essence, the concrete burns the foil and renders the board much less effective"),  To the extent that my answer addressed that statement, I believe it's correct. 

I'm confuddled now...  Are you saying your statement that it is irrelevant if foil is intact or not is correct despite what BBA certs and manufacturers say about the importance of keeping the foil intact?  

 

9 minutes ago, jack said:

I'd be interested to know how much hydrogen is generated and how deeply it potentially penetrates the concrete in a Durisol application. I suspect the risk is much higher in a flooring application, where the bubbles are formed underneath a layer of concrete, and could rise into it through buoyancy. In the Durisol application, the hydrogen bubbles would need to move horizontally into the concrete to cause trouble, based on their relative positions in a Durisol wall. Seems less likely than the flooring case.

 

Well here's the actual answer:

 

The reaction of Aluminum with fresh concrete

3 parts Calcium Hydroxide + 2 parts Aluminum
3 Ca(OH)2 + 2 Al -> 3 Ca3Al2O6 + 3 H2

 

3 parts TriCalcium Aluminate + 3 parts Hydrogen
3Ca+ 6OH- + 2 Al -> 3 Ca3Al2O6 + 3 H2
Within the first 24 hours

 

In a flooring scenario, it would only be a concern where there are loads coming down on the areas affected - generally unlikely.  However, in a vertical application, like Durisol, it is impacting on the walls where you are transferring significant loads. you are right that you would need the bubbles to move horizontally, however that is relying on reactions to be uniform across the board.  Not to mention that the insulation itself is not doing what it is supposed to.  Oh - and you have an air permeable product that links the outside world to in...

 

My test is always - leave the product you want to build with out in the rain for a few weeks - if it is still as new, then use it.  If not, then why would you want to put your loved ones into an envelope structure made of something that can't even sustain a few weeks of our wonderful weather?

[ToughButterCup]

26 minutes ago, najem-icf said:

[...]

My test is always - leave the product you want to build with out in the rain for a few weeks - if it is still as new, then use it.  If not, then why would you want to put your loved ones into an envelope structure made of something that can't even sustain a few weeks of our wonderful weather?

 

My Durisol blocks have been out in the rain for a minimum of two months on site and one month outside before delivery. Some blocks have been on site here for nine months.

 

29 minutes ago, najem-icf said:

[...]

if it is still as new, then use it.  If not, then why would you want to put your loved ones into an envelope structure made of something that can't even sustain a few weeks of our wonderful weather?

 

So I used it.

[najem-icf]

Awesome :-)

 

A guy I know who was at the coalface told me differently.  Are you saying you experienced zero crumbling of the block in the rain?

 

When I first looked at ICF, I looked at their biggest market in the world - North America - and I saw what they use there. Went to the World of Concrete Conference in Las Vegas. Lots of ICFs there, predominantly EPS based ones. Durisol wasn't there. It isn't very widely used in North America at all.

[ToughButterCup]

4 minutes ago, najem-icf said:

A guy I know who was at the coalface told me differently.  Are you saying you experienced zero crumbling of the block in the rain?

 

Yes.

[jack]

6 minutes ago, najem-icf said:

I'm confuddled now...  Are you saying your statement that it is irrelevant if foil is intact or not is correct despite what BBA certs and manufacturers say about the importance of keeping the foil intact?  

 

You're putting words in my mouth now  

 

You said In essence, the concrete burns the foil and renders the board much less effective. I read that as you saying that the loss of the aluminium had a significant impact on the insulation effectiveness of the board. I was simply making the point that the foil contributes nothing to the insulation of the board in an application where there is no air gap (as with Durisol). That's a fact, hence me saying To the extent that my answer addressed that statement, I believe it's correct. 

 

If you were saying that damaging the aluminium layer allows subsequent meaningful damage to the underlying board rendering it much less effective, then that isn't something I'm qualified to address. I also don't know exactly what the manufacturers say, nor why they say it.

 

14 minutes ago, najem-icf said:

Well here's the actual answer:

 

My question was about how much hydrogen is generated and how deeply it potentially penetrates the concrete in a Durisol application. The reactions alone don't provide an answer to that. You also need to look into things like foil thickness (ie, how much hydrogen is generated per unit area) and what the dynamics are of hydrogen gas in this structural arrangement. Again, I'm unqualified to comment, although I have a gut feeling that the damage isn't going to be as bad as you're suggesting. 

 

42 minutes ago, najem-icf said:

My test is always - leave the product you want to build with out in the rain for a few weeks - if it is still as new, then use it.  If not, then why would you want to put your loved ones into an envelope structure made of something that can't even sustain a few weeks of our wonderful weather?

 

I have pieces of treated softwood left over from the start of our build that have been out in the elements for over two and a half years and they're perfectly fine other than some surface bleaching from the sun. I imagine they'd be in even better condition had they been positioned within an envelope that largely protects them from the vagueries of the British weather. 

I also have a several hundred year old house just around the corner from that that's still on its original wooden frame. Not softwood, admittedly, but it does illustrate that not all organic material is the same.

 

Durisol says they "mineralise" the wood before they encapsulate it. Anyone know what that means?

[jamiehamy]

This thread is getting dull. It's turning into 'Cons of Durisol'. @najem-icf. I sense you have an agenda here. 11 posts and you're trying to discredit Durisol. I don't care whether you are right or wrong, it's not a good look mate. 

[najem-icf]

Sorry @jamiehamy - Durisol was named by a previous poster and they asked about pros and cons of different ICF systems. The detailed discussion on Durisol has been carried by various replies, not just myself.  I don't have an agenda other than to inform people of my own experiences and knowledge. Inevitably each of us has likes, dislikes and extreme opinions about every aspect of life.

[ToughButterCup]

15 minutes ago, jack said:

[...]

Durisol says they "mineralise" the wood before they encapsulate it. Anyone know what that means?

 

Take the sugars and proteins out of the wood and coat it with cement. I cannot evidence that process, nor verify it. I just use the stuff.

Other ICF systems are available, and are probably more interesting.

[Russell griffiths]

can you tell us why your user name is @najem-icf

Edited September 15, 2017 by Russell griffiths
Cock up

[najem-icf]

@Russell griffithsNajem is my first name and my preferred method of construction is ICF. It's what I have the most knowledge about.

Edited September 15, 2017 by najem-icf

[Construction Channel]

15 minutes ago, Russell griffiths said:

can you tell us why your user name is @najem-icf

 

in fairness to Naj he did post in the introduce yourself section

 

I can't say much about the rest of his posts as ICF is not my favoured build method, but as for his name, he did at least explain himself  

[jamiehamy]

32 minutes ago, najem-icf said:

Sorry @jamiehamy

 

extreme opinions about every aspect of life.

I think it's that - maybe bordering on a bit  obsessive. Your points have been made and there for consideration - it's maybe that you're coming across a bit strong tis all!

[Russell griffiths]

I was going to read all @najem-icf posts to see the reason but I was being lazy so just asked the question. 

No disrespect was intended, but from reading this thread it does read like build with icf because everything else is shit. 

By the way I intend using icf, but have previously built timberframe,and I'm also a bricklayer, but won't be building using brick or block. 

Work that out. 

[Construction Channel]

2 minutes ago, Russell griffiths said:

I was going to read all @najem-icf posts to see the reason but I was being lazy so just asked the question. 

No disrespect was intended, but from reading this thread it does read like build with icf because everything else is shit. 

By the way I intend using icf, but have previously built timberframe,and I'm also a bricklayer, but won't be building using brick or block. 

Work that out. 

 

Im a chippie that decided to put a brick skin on my timber frame.

I think the short answer is that were all idiots and thought it might be nice to change it up a bit..... 

[najem-icf]

4 minutes ago, Russell griffiths said:

I'm also a bricklayer, but won't be building using brick or block. 

Work that out. 

@Russell griffiths a friend of mine is a carpet fitter - yet has no carpets in his own house - so I totally get that...  When I was in IT, last thing I wanted to do was fix my own computer issues...

 

 

[Tennentslager]

I'm enjoying this thread...nothing wrong with an alternative view @jamiehamy and a bit of debate.

To me ICF was a gang of hooligan so called football fans who liked a rumble at away games...no good for hut building so I'm out?

Edited September 15, 2017 by Tennentslager
Typo

[Jeremy Harris]

The stuff about aluminium "foil" on PIR is just a bit of scaremongering.  Go and look at a sheet of PIR.  What you will find is that the silver surface is really silver paper, with a thin glass fibre scrim under some types.  It is not aluminium foil, as such, or if it is it is only a few microns thick as a coating on some form of binder, and as such there is not enough of it to react in in any significant way with wet concrete, at least not to any degree worth worrying about, let alone debating to the nth degree.

 

This afternoon I pulled a bit of scrap 50mm Celotex out and peeled off the silver layer, and I can say with absolute certainty that it is some form of "silver" coated or painted paper-like material.  I'll take some photos on Monday if there is any doubt about this.

[Nickfromwales]

It's so much better when all the kids play nicely together. . 

 

[Nickfromwales]

2 minutes ago, JSHarris said:

This afternoon I pulled a bit of scrap 50mm Celotex out and peeled off the silver layer, and I can say with absolute certainty that it is some form of "silver" coated or painted paper-like material.  I'll take some photos on Monday if there is any doubt about this.

Agree. It's wafer thin. Just putting gaffa tape on it and peeling it away shows just how thin it is. 

[jack]

33 minutes ago, Nickfromwales said:

It's so much better when all the kids play nicely together. . 

 

Gawd dad, you're so embarrassing.

 

I'll be in my room.