I’ve no technical input, but my local council has 6 high rise blocks which were clad in polystyrene and render ewi about 15 years ago, post grenfell its been decided that this is unacceptable and needs to be replaced, it was originally suggested that the cost would be 12 million for the 6 blocks, the surveyor i use just laughed and said he’d be amazed if they could do one for that. All gone very quiet since the initial announcement.
So i’d guess that there’s no appetite for putting ( or keeping ) anything that may present a risk on a building.

Councils, housing associations, surveyors etc etc are very risk adverse and unlikely to specify any new work with products that may be seen as any sort of problem, ( if for no other reason than there being further legislative changes in the future), take all those clients out of the mix and you’ve a pretty small market that won’t really be worth catering for.

Very bad news if it turns out to be true. IMO not using EPS on your standard family house because of Grenfell is a nonsense.
Over here mineral fibre is 2.7 x the price of EPS, is a pain to put up and needs mechanical fixing and if water ever gets in due to damage to the render then you have wet insulation that will need fixing whereas EPS is easy to put up, in most cases doesn't need mechanical fixing (important with retro-fit stone buildings) and is not degraded by water.
The cost of mineral fibre wall insulation will probably stop the vast majority of retrofit upgrades to the housing stock - EWI is already a cost marginal improvement.

Posted By: fostertomSuits me.

While energy/CO2e 'in-use' seemed all-important, 'embodied' less so, I've standardised on EPS EWI as best insulation for the money (in-use), available and easy to use, while also at least much less harmful (embodied) compared with all other plastics. Coupled with blown-in cellulose on newbuild.

Now 'embodied' seems the primary one, so I hope I've specd my last major plastics, so from now on woodfibre for retrofit despite cost, unavailability in comparable thickness, weight to handle, mech fixings, faff in general. I 've hoped that woodfibre cost wd move from 'premium for zealots' to mainstream, as it is in Europe (I thought - but Peter says no).

For newbuild, my hybrid standard involved EPS EWI outboard of sheathed stud (for versatility) filled with blown cellulose; now switching to I-joists with blown cellulose right through. I worry about the outer flange and outer cellulose sitting in the intermittent condensation zone.

Mindful that at the same time, sequestered bio-materials have become no longer the unquestioned ideal.

What's prompted your switch in priority from "in-use" to "embodied"?

Posted By: fostertomNow 'embodied' seems the primary one, so I hope I've specd my last major plastics, so from now on woodfibre for retrofit

But surely woodfibre is caught by the same gotcha as EPS. It's not inflammable (whatever the European symbols for that are).

Posted By: lineweightWhat's prompted your switch in priority from "in-use" to "embodied"?

I've not read the book Fostertom refers to, but in a nutshell for the industry at large it's because the climate crisis is now so urgent and the grid sufficiently decarbonised that the impact of 'up front' material choices now often outweighs the impact of the longer term operational use.

So the carbon 'burp' during construction has more severe short term impacts due to the fact that it is released *now* while the world is rapidly warming rather than in the future when we may all be under water anyway!

I remain slightly skeptical about how much of all this carbon accountancy relies on 'magical thinking' about the extent to which the grid will have decarbonised in the future - clearly if we suddenly reopen all our coal mines the pendulum would swing back the other way.

But that said, lower impact materials are clearly better, by definition, so we need to be doing all of it - demand reduction and reduced embodied energy, and I'm happy to join the bandwagon on this one.

Posted By: WillInAberdeenIt's a minefield....

The EPD for a well-known brand of woodfibre insulation says that over its lifecycle including disposal, it emits 160 kgCO2eq per m³, mostly from the heat and electricity used to bake it.

This doesn't include the CO2 for transporting the heavy bulky boards from Germany to a site in the UK.
Doesn't include the embodied CO2 of the cement to stick it on or the render to keep it dry.


The EPD for a well known brand of glass wool says 31kgCO2eq for the same insulation value - so much better. Also doesn't include transport from Merseyside to site (but it's lighter and packs small) and fixings or render.


The EPD for a generic graphite EPS insulation says 26kgCO2eq for the same insulation value - half from manufacturing and half from assumed incineration at end of life - though they suggested energy recovery from the incineration would nullify those emissions.

Who to believe ?!?

This is my problem when trying to take embodied energy into account. Which & whose numbers to believe/trust.

Posted By: Artiglio99% plus of home owners who want to go for EWI will be dealing with architects, designers, installers and so will ne guided by what the professionals deem the best option. Very few people will ne like yourself and be exploring every option seeking the ultimate solution.

I'm a designer/specifier often working for home owners and so have to form an opinion on the best option(s) are for them. Options like phenolic or EPS are very mainstream ones so it would be odd not to explore them.

Am I "risk averse"? Well, if I'm giving advice to a home owner I'm a little more risk averse than when I'm considering something for my own use perhaps. But I'd see it as a responsibility to look at those (at least until now) mainstream options that are also the most affordable ones.

The fact that Weber has withdrawn phenolic and is going to withdraw EPS certainly gets the attention of the "risk averse" bit of me because naturally I wonder why. Hence this thread really; I'm interested in whether it's a decision that all/most manufacturers are taking.

If it looks like the reason that they are being withdrawn is that certifications are going to run out, and they don't believe they are going to be able to get them renewed, then that certainly raises many questions, like whether the current certifications don't take certain things into account and therefore don't recognise certain risks.

But risk-averse designers/specifiers being an explanation in itself for the withdrawal of products ... I don't think that really adds up. They'll only be concerned if it looks like there's something to be concerned about. If what they are concerned about is whether certifications aren't going to stand up in the future, then we are back to being the fundamental reason.

Posted By: Peter_in_HungaryDoes each manufacturer have to get certification for any material/product in their own right or is a material/product produced to the standard get the certification automaticity?

For things like BBA certificates (which aren't mandatory) each manufacturer has to get its own, I think.

There are all sorts of different certifications around.

I guess EPS etc will continue to be available for other purposes - IWI, underfloor - so availability shouldn't dry up. It's more that Bldg Insps will want to see Certification fot the EWI purpose?

Posted By: lineweightwhy are they continuing to offer it for sale until the end of this year.

To sell their existing stocks? Or is that too cynical?