Key Post Poroton Blocks

[angela59]

Re: Key Post: Poroton Blocks

Hi BarneyMc,

In your opinion do you think it is cheaper to build a "normal" block house with blow in insulation which give you as good a U value? Like SAS have done the rounds of timber frame SIP houses then back to poroton but if FBT would back up the blower test it begs a lot of questions?

 

[sydthebeat]

Re: Key Post: Poroton Blocks

Hi BarneyMc,

In your opinion do you think it is cheaper to build a "normal" block house with blow in insulation which give you as good a U value? Like SAS have done the rounds of timber frame SIP houses then back to poroton but if FBT would back up the blower test it begs a lot of questions?

It wont give you 'as good' a u value.

pumped in insulation into a standard 100mm cavity wall generally will only give a u value of 0.3.
If you use a (more expensive) aerated autoclaved concrete blocks as the inner leaf, then theoretically you can get this down to 0.24... still not good and probably may not even met the new regs coming up in July.

 

[angela59]

Re: Key Post: Poroton Blocks

hi Sydthebeat,

Thanks for that. I ask because poroton is so expensive! By the way I haven't met with BER assessor yet but the quote was for E600 plus VAT no extras on top of this. When are drawings are finished he will go through with us and advise what heat types etc and I presume he will be able to give us an energy rate from the drawings.

 

[sydthebeat]

Re: Key Post: Poroton Blocks

hi Sydthebeat,

Thanks for that. I ask because poroton is so expensive! By the way I haven't met with BER assessor yet but the quote was for E600 plus VAT no extras on top of this. When are drawings are finished he will go through with us and advise what heat types etc and I presume he will be able to give us an energy rate from the drawings.

he will give you a provisional BER from the drawings before construction... on completion and before occupancy he can give you a Final BER...

his quote sounds about right... he doesn't sound like one of these 'fly by night' companies who throw out BERs like fast food. I would ask him what construction experience he has and if hes able to stand over the practicalities of his advice.

 

[BarneyMc]

Re: Key Post: Poroton Blocks

Hi BarneyMc,

In your opinion do you think it is cheaper to build a "normal" block house with blow in insulation which give you as good a U value? Like SAS have done the rounds of timber frame SIP houses then back to poroton but if FBT would back up the blower test it begs a lot of questions?

Hi Angela, that's what I'm trying to do... almost there. All prices inc. VAT...

Poroton House
Materials from FBT (T-10 Blocks, lintels, mortar, etc.) = €35,000
Labour (rough quote) = €15
Total Cost €50K
U Value of 0.25

Cavity House
Have not priced labour or materials but it is a 1.5 storey dormer with sunroom to the side, 2,900 sq feet (275m2). [anyone estimate this?]
Blown in bonded bead quote = €2,850
Total Cost = can anyone estimate?
U Value of 0.15 can be achieved - 150mm cavity filled with bonded beads (this is based on calculations found at post #30 at http://www.askaboutmoney.com/showthread.php?t=67603&page=2)

 

[BarneyMc]

Re: Key Post: Poroton Blocks

If you use a (more expensive) aerated autoclaved concrete blocks as the inner leaf, then theoretically you can get this down to 0.24... still not good and probably may not even met the new regs coming up in July.

Hi Syd,

I thought poroton T9, T10 and T12 can only achieve 0.23, 0.25 and 0.27 respectly? If so then they won't meet the regs either?

Does the Quinn Lite block come under the "autoclaved concrete blocks" category and if so my calculations found the standard concrete block to give almost as good a u value: [broken link removed]

Me is lost!!!!

 

[sas]

Re: Key Post: Poroton Blocks

Hi Syd,

I thought poroton T9, T10 and T12 can only achieve 0.23, 0.25 and 0.27 respectly? If so then they won't meet the regs either?

Does the Quinn Lite block come under the "autoclaved concrete blocks" category and if so my calculations found the standard concrete block to give almost as good a u value: [broken link removed]

Me is lost!!!!

Thats actually a very good point. FBT could actually find themselves in trouble because their "bread and butter" products fall short under the new regs. Having said that it also affects the Nudura, Euromac and Amvic ICF systems too unless you want to dryline.
The biggest issue with poroton is the lack of extensibility. You can't\shouldn't dryline it. Externally insulating it is not recommended by FBT either so its a little frustrating how limited it is.

Quinn Lite is an aac product.

 

[sydthebeat]

Re: Key Post: Poroton Blocks

Barney, please see my post in the 'partial fill cavity: dead?' thread... my pumped in calculations were incorrect... i am sorry now if your calculations are based on them.... my TC values were incorrect. On further investigations the pumped in suppliers were calculating u values using non-standard construction.

a few points on this thread.

one of the main advantages of poroton is the breathability of the construction and its ability to diffuse moisture to the external. This would be completely compromised if a product such as EPS, PU, PIR or phenolic is used.. especially in a drylining situation, so that should not be considered.

barney, you are correct to state that T10 and T12 most probably will not meet new regs. The T8 is the only real viable option.

At least the ICF crowds can increase their forms to achieve appropriate regs, its not so easy for FBT.

 

[ninsaga]

Re: Key Post: Poroton Blocks

The biggest issue with poroton is the lack of extensibility. You can't\shouldn't dryline it. Externally insulating it is not recommended by FBT either so its a little frustrating how limited it is.

That guy who runs viking house is insulating poroton externally with 100mm Poroc though

 

[sas]

Re: Key Post: Poroton Blocks

That guy who runs viking house is insulating poroton externally with 100mm Poroc though

Just because he's doing it doesn't mean he should. Paroc for example won't actually stand over this I was told elsewhere. Plus he has dropped this option now in favour of the simpler T8 build based on the website.

There is a picture of external insulation on a regular poroton block (i.e not perlite) on the Wienerberger website so its something that is done. Its just not done by anyone here.

Plus external insulation is damn expensive before you factor in poroton.

 

[BarneyMc]

Re: Key Post: Poroton Blocks

barney, you are correct to state that T10 and T12 most probably will not meet new regs. The T8 is the only real viable option.

Does this mean the price of the T8 and other better blocks will come down in price as they will become the standard poroton block? Anyway it seems like the new regs will push a lot of building techniques to the very limit and squeeze out others!!

 

[sas]

Re: Key Post: Poroton Blocks

I doubt it. The cost of a t8 between here and germany is about 3 euro. Taking shipping and the fact that FBT have to make their cut it would seem unlikely.

Any cost reductions will have to be done at source i.e. wiernerberger

 

[Eve001]

Re: Key Post: Poroton Blocks

Use poroton blocks. Then plastered them internally with MP1 plaster from FBT. Now having a problem with painting onto this. Has anyone else used MP1, what was your experience ?