Key Post Poroton Blocks

Re: Key Post: Poroton Blocks

disgruntled said:
hi all
i have a two storey extension built with poroton blocks and i had the whole house insulated externally with paroc wool.the house is very warm,i have never timed the heating to come on in the morning,house retains heat no problem,however i have two problems with this type of build i have no ventilation in my new extension so the house becomes unbearably hot and stuffy. another prboblem i have is rain water from outside coming into my sunroom under the skirting boards apparently due to this single leaf system.i am not a builder so do not fully understand what my so called sustainable builder was trying to do.all i do know is he made a mess of my house.be very careful who you choose to do this work.i am all for sustainable building but there are an awful lot of chancers out there.
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why is the rain coming in at one area only do you think? - did the builder forget/neglect to do something?
 
Re: Key Post: Poroton Blocks

disgruntled said:
hi all
i have a two storey extension built with poroton blocks and i had the whole house insulated externally with paroc wool.the house is very warm,i have never timed the heating to come on in the morning,house retains heat no problem,however i have two problems with this type of build i have no ventilation in my new extension so the house becomes unbearably hot and stuffy. another prboblem i have is rain water from outside coming into my sunroom under the skirting boards apparently due to this single leaf system.i am not a builder so do not fully understand what my so called sustainable builder was trying to do.all i do know is he made a mess of my house.be very careful who you choose to do this work.i am all for sustainable building but there are an awful lot of chancers out there.
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Disgruntled, you need to be careful about dumping all over a system because you got messed about by a builder. The rainwater entering your house is highly unlikely to have anything to do with the single leaf system and alot more to do with incorrectly installed damp proof courses.

If you build a regular 2 leaf block wall and then let mortar drop into the cavity as the walls rise, that too would breach the dpc and allow water enter into the house.

It comes down to the quality of the workmanship.

Poroton has a IAB cert i.e. it is completely suitable for use in our climate.

I am in no way affiliated with any seller\manufacturer of poroton. I am never happy to see a system getting slammed for the wrong reasons though.
 
Re: Key Post: Poroton Blocks

sorry sas
i am not critisizing the poroton blocks. i believe building better insulated homes is the way forward.unfortunately there is nobody policing these builds,there are a lot of chancers out there.my architect tells me the reason i have water coming is because the whole extension is built at ground level and the dpc is set too low.i find it incredible a builder could make such a mistake,but then again when i look around the house i am not surprised at all.poroton blocks are definitely the way forward but be careful there is a guy in dublin claiming to use poroton blocks but is actually using an inferior product,check it out with wolfgang in fbt before hand

thanks
 
Re: Key Post: Poroton Blocks

hi all,

just going back to a point ollie30 made about the u value benefit's of the standard T12 poroton blocks, my concern is that if they only offer a similar u-value to that which could be achieved with a standard concrete build with the right type of insulation, then thermally anyway, they don't appear to offer any advantages. Yes I appreciate the advantages of a offering a faster build time with being a single leaf system, but the appeal to me was of the insulating properties rather than the build time. So unless you were to go for the very expensive T8/T9 perlite block, they may not be any better than a concrete option that may even be cheaper?

Anybody have any tought's on this?
 
Re: Key Post: Poroton Blocks

Well, you can still insulate inside the poroton blocks anyway, with insulated plasterboard.
 
Re: Key Post: Poroton Blocks

hi exteopia,

but if you were going to insulate the internal part of the wall then concrete with the right insulation would probably work out cheaper. part of the benefit of the poroton block is it's high insulation properties, but from what I can see it's no better than using concrete with the right type of insulation.
 
Re: Key Post: Poroton Blocks

Hi, A quick question on what you use when attaching heavy objects to FBT blocks. The internal plaster is FBT also. I am attaching a marble electric heater from SmartSol (30kg) and a large TV (which will be 25-30Kg also)?
 
Re: Key Post: Poroton Blocks

hi mallowdave
no normal fixings will hold on poroton blocks,i speak from experience,my cooker hood fell of the wall!we had to make wooden dowels about eight inches long drill a hole in the wall and hammer it in.basic but it works very well.alternatively speak to wolfgang in fbt he should be able to advise you.
 
Re: Key Post: Poroton Blocks

MallowDave said:
Hi, A quick question on what you use when attaching heavy objects to FBT blocks. The internal plaster is FBT also. I am attaching a marble electric heater from SmartSol (30kg) and a large TV (which will be 25-30Kg also)?
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Just asked Padraic in FBT about fixing windows to poroton.
He refered me to http://www.masonryfixings.ie to get a special wall plug.
I called them but the guy on the phone said he'd have to research and get back to me.
 
Re: Key Post: Poroton Blocks

Hi Prosta, welcome to AAM. In accordance with the posting guidelines, could you confirm whether you have any association with the above companies other then being a satisfied customer?
Thanks,
Leo
 
Re: Key Post: Poroton Blocks

Just a customer. Some pics of the build on [broken link removed]

George Allis is the Field Engineer for Poroton with Masonry Fixings.
He sent some brochures for fixings. I guess I cant attach them here.

Info is available from http://www.fischer.co.uk/.

The types he suggested are:

Universal frame fixing FUR
Plug SX
Universal Plug UX

FIS HM - mad looking chemical injection stuff.

I went with the FUR 8 x 80 SS A4 and FUR 8 x 100 SS A4 cause they had them in stock but 50 of each cost me €146 :eek:

In the end they just look like the rawlplug things you can get in Woodies
 
Re: Key Post: Poroton Blocks

Prosta,
Well done on your project...it's some achievement!!! Jus curious...the stone facing you used......do you have any info on how the stone facing may effect the performance of the poroton block. ie can moisture travel out through the mortar in the stone facing? Will moisture from inside the house get trapped in the cavity between the stone facing and the poroton? Will rain pass through the mortar joints in the stone facing and pass through the un plastered poroton blocks behind?? I saw a guy in Sligo using stone facing on poroton but he used Tyvek membrane between the poroton and the stone facing??
 
Re: Key Post: Poroton Blocks

Can anyone let me know what problems if any the general electrical work encountered? Can an electrician work away as normal or are there any differences (more expensive?) a standard electrician will encounter?
 
Re: Key Post: Poroton Blocks

Have got a quote from FBT for poroton materials but am wary of the ability of builders to be trained up in one day! If anyone has used poroton can you please let me know how your builders got on? As poroton is the standar in eastern europen countries then maybe it would be possible to get an experienced eastern europen builder based here in Ireland to take this on?

Also if anyone in the north east has used poroton I'd be very interested in visiting their house or even just a quick reply on how warm/cold it was over the winter.
 
Re: Key Post: Poroton Blocks

BarneyMc said:
Have got a quote from FBT for poroton materials but am wary of the ability of builders to be trained up in one day! If anyone has used poroton can you please let me know how your builders got on? As poroton is the standar in eastern europen countries then maybe it would be possible to get an experienced eastern europen builder based here in Ireland to take this on?

Also if anyone in the north east has used poroton I'd be very interested in visiting their house or even just a quick reply on how warm/cold it was over the winter.
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Yes BarneyMc, it is worth to hire eastern/central european bircklayers because they have many years of experience.
Although this thin-bed technology is simpler than the thick-bed one, I don't think that the shortly trained labourers can make the same performance and are ready to solve the more complicated junctions.
I saw such wavy wall that I asked them to disjoint it. And what did the labourer say? "It will will be plastered anyway."...
 
Re: Key Post: Poroton Blocks

There's a lot of talk recently on air tightness and how the single leaf system like poroton is so air tight compared with cavity walls. I went to see a pototon house being built before Christmas and was a bit shocked at how the blocks sat horizontally with each other. Some of the blocks didn't sit totally square or snug against each other horizontally. Any thoughts on how airtight portotn build really is?
 
Re: Key Post: Poroton Blocks

BarneyMc said:
There's a lot of talk recently on air tightness and how the single leaf system like poroton is so air tight compared with cavity walls. I went to see a pototon house being built before Christmas and was a bit shocked at how the blocks sat horizontally with each other. Some of the blocks didn't sit totally square or snug against each other horizontally. Any thoughts on how airtight portotn build really is?
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I have some pretty big concerns myself on exactly the same thing at the moment. I had decided on the poroton T8 route (i.e. my footings are in specifically designed for the T8) but like yourself visited a poroton build recently. I'd seen 2 others in the past too and in all cases I've been concerned by the gaps in the blocks. I had put the first 2 down to bad workmanship but its starting to bother me seriously now after my 3rd house. I've even started looking seriously at ICF again and the price difference is considerable compared to the T8. The answer I keep getting on the gaps is that you can fill them with the insulated mortar. This has the same insulating quality as the clay which is fine for the regular poroton blocks, but not the T8s. I've contacted FBT twice in the last fortnight and asked them to arrange a site visit to a T8 build for me anywhere in the country that is actually being laid correctly. They have yet to arrange anything.

FBT haven't done a blower door test on a house before. The reason they gave was that there are so many other elements that can cause issues that there isn't any point. This is a load of crap imho because ICF companies who only have walling systems have been able to provide me with blower test results. This concerns me. They also claim that the thermal imaging camera gives a much better idea of the effect of poroton. This too is a load of crap because the outside wall will appear cold if the house is very wall insulated and very warm inside, it will also appear cold if the house isn't insulated at all and there is no heating in the house. Its easy to fudge the results of the thermal scan.

The poroton build depends on the internal plaster for its airtightness I'm told. Fair enough, regular blockwork can be made airtight in the same way I've heard so this potentially is true. Also, poroton T8s are used to build the solar houses (next gen. passive houses I believe) so they must perform well. Thats assuming that they are used without membranes etc.

This is really annoying me at the moment...

End of rant

SAS
 
Re: Key Post: Poroton Blocks

Hi SAS,

So it's not just me then! I was hoping someone would correct me!! I had a look at one ICF houses also but am just not sure about how the insulation on outside and inside really performs. I also saw some really bad ICF houses where water was leaking through it!!

If you want a 'solid wall' construct method then you can always build a "cavity" wall and fill it with insulation. If you look at http://www.askaboutmoney.com/showthread.php?t=67603&page=2 there are a few suggestions for how best to construct a cavity wall. The results (on paper) are good. I think bad workmanship, poor levels of insulation and narrow (<150mm) cavities are to blame rather then the actual construction method itself.

Anyway it's hard to know!!
PS: Sorry, this is still a Poroton thread!!
 
Re: Key Post: Poroton Blocks

BarneyMc said:
Hi SAS,

So it's not just me then! I was hoping someone would correct me!! I had a look at one ICF houses also but am just not sure about how the insulation on outside and inside really performs. I also saw some really bad ICF houses where water was leaking through it!!

If you want a 'solid wall' construct method then you can always build a "cavity" wall and fill it with insulation. If you look at http://www.askaboutmoney.com/showthread.php?t=67603&page=2 there are a few suggestions for how best to construct a cavity wall. The results (on paper) are good. I think bad workmanship, poor levels of insulation and narrow (<150mm) cavities are to blame rather then the actual construction method itself.

Anyway it's hard to know!!
PS: Sorry, this is still a Poroton thread!!
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That's the problem with the ICF structure, BarneyMc! The external and internal leaf is the most vulnerable layer in within the structure, it should inside of the wall I think. It look like a wrong-side out structure.
I saw buildings on real estates where the kids enjoyed that they throw subjects at the wall and it stayed there digged into the insulation. Good game.
And the situation is the same with the internal leaf, and I didn't mention the condensation between the inner leaf insulation and the concrete core.
 
Re: Key Post: Poroton Blocks

sas said:
FBT haven't done a blower door test on a house before. The reason they gave was that there are so many other elements that can cause issues that there isn't any point.
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Yes that's not a very convincing answer from FBT who have a monopoly on Poroton in Ireland. To my untrained eye poroton build looks very leaky where air tightness is concerned and air tightness is now seen as probably more impoortant than anything. So perhaps poroton is great on paper but not in practice?

Cavity wall builds have taken a blasting on this site but if the cavity is filled with blown in bonded bead insulation and perhaps 150mm cavity then can this build be still called a "cavity" build any more? There is no cavity any longer, in fact it is a single leaf with rigid exterior and interior and insulated core. Poroton in fact is made up of numerous cavities throughout the block!!

A lot has been made also about the poor workmanship of builders of cavity wall houses and this is very true - they generally don't take care with rigid insulation. Looking at some of the poroton builds this may also be true. A gap here and there (as there seems to be in these builds) is not at all satisfactory. As SAS pointed out why are FBT so reluctant to employ the blower test?
 
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