Poroton Block, T9

Extopia, I'm very interested to hear that you took on the poroton build yourself as this is something that I am considering. I'd love to hear more from you - how large was the project? How long did it take? Did you just do the blockwork or did you also put in foundations & woodwork etc?

In my case, I have an old farmhouse that I am going to build an extension to in Poroton (at least that's the current plan anyway!) I intend to re-render the original building in lime while I'm at it.
 

Claiming something is commonly done and claiming something is good building practise are very different things in my opinion. Installing insulation the correct way is good building practise but is it commomly done? Example, the 6 year old 1345 sq ft house I currently live in that burns through more than 1500 euros of oil (at 2005 prices) for a house thats empty during the day 5 days a week. The main heating at the week ends is an open fire.

Seeing as the IAB is linked off the NSAI web site I tend to group them into one, but point taken, the IAB issue the certs.

Thanks for the clarification on YTong.
 

Now Maggie lets not fall out over this. Your first post asked no question, you simply waded in with a very negative opinion on the system the OP asked about. You stated you know other people who've also decided against the system in the process damning it further. After I looked for some clarification as to what your reasoning was you pointed out the photos on FBTs website and then asked your question.

All the responses you got were related to what you had deduced from the photos and all were deserved I feel.

Anyway, I've got some of the recent prices which in the interest of building bridges I'll pm to you. I'm not posting them in the thread as I don't think its appropriate.

SAS
 
Hi,

The poroton blocks I'm looking at are the T9 365 costs E6.79 per block - not sure per meter. This particular block contains perlite. They seem to be expensive but if you go for normal block you're going to have to pay for insulation which can be expensive on top of your normal block. Ask FBT to forward an information pack. I think it is like everything at the moment - do all the research before jumping in.
 

Bankrupt, explore this key post thread.
 
I'm "borrowing" the thread, since a lot of knowledgable people appear to be posting!

We're currently planning a substantial extension (fingers crossed on the PP, on which we should be getting a decision soon), and are keen to build to high environmental / insulation standards. I've been thinking about the poroton perlite-filled block, but the major complicating factor is that most of the extension, to fit in with the existing house, will have to be pebble-dashed.

Can anyone comment, before I go any further in exploring possibilities, on whether this will just rule out the poroton blocks, since I gather the render must be breathable?
 
Firstly, I would like to thank Extopia for answering my questions regarding dampness and cold bridging. It is comforting to know that my preconceived fears about long-term water retention were slightly misguided. Sas, I have read your message regarding Poroton prices. Poroton’s U-values are reasonably good but I must admit that Poroton is a very expensive building material.

Polonius can you give me an idea on pricing for Ytong blocks? What U-values can be achieved with Ytong?
 
Per Ecostein's web site, the U values for Ytong are from .23 to .11 depending upon what materials you use see [broken link removed]

would be interested to know how this works out cost wise - not to mind the fact that most builders will probably shy away from it as they've never seen ot before.

ninsaga
 
I've been thinking about the poroton perlite-filled block, but the major complicating factor is that most of the extension, to fit in with the existing house, will have to be pebble-dashed.

You should call Wolfgang in FBT about this - you could be right but perhaps it's possible to do a breathable pebbledash with the MFL plaster that's recommended for poroton builds.
 
Hi Polonius,

From the figures that Sas was kind enough to share with me through PM I was able to calculate the price for a square metre of Poroton T9 wall. I’ll illustrate my calculations so there’s no confusion.

Given that the T9s are 248mm long it takes 4.032 T9s to make up a metre and 16.25 T9s for one square metre. Since there are 60 T9 blocks in one pallet then there are 3.7 square metres worth of wall in one pallet (60/16.25). The price per pallet is €407.40 Therefore, for one square metre of Poroton T9 wall, the cost is €110.10 (€407.40/3.7) The U-Value for this wall is 0.23

Polonius, I would very much appreciate it, if you could include in your costing a square metre price for an Ytong wall so I can make a direct comparison between the above figure for Poroton and the figure for Ytong.
 
I believe those blocks are not laid on their end as you describe - you need to calculate your cost per square metre based on the "square" end of the block, not its length. The blocks I used were abotu 300mm square on the end, or about 10 blocks per sq metre.
 
As far as I’m aware, and correct me if I’m wrong, the face area of a poroton block is about 0.25 m x 0.25 m (248 mm x 249 mm). To cover one square metre of wall, I would need 4 x 4 blocks = 16 blocks / m2. As I got worried about my maths skills, I had to check out the Wienerberger website. With my basic knowledge of german I found I was actually right. (Here is the link to the translation site confirming my sums – see material requirement / m2: [broken link removed]

You’re sure you laid your blocks the right way?
 

The paper work I have from FBT for my quote has all external blocks as 16 per m2.
 

The ecostein site gives prices per sq METRE
Look under the downloads tab and you will see prices list.

€127 -- €131 sq m etc
 
Hi Bakerbhoy,
I’m afraid you are very much mistaken in saying that these prices are square metre prices. The figures you posted are correct, but they relate to prices per cubic metre (i.e. m3) and not per square metre (i.e. m2). [broken link removed]
 

Maggie,

I had a look at that link too and I think you can apply the same method you did to get the poroton per sq metre quote.

I.e. The Ytong blocks (last one in the table) are 60 cm long * 25 cm high. I'm assuming the 36.5 is the depth (i.e. same as the T9 in the case of a monolithic wall).

So each block is 0.15 sq metres of wall at a price of 6.46 + VAT.
So 1 square metre of wall is approx 43Euro + VAt = €52 approx.

SAS
 


Apologies for wrong info but thanks for that .I had ruled them out as being more costly than the poroton. Mine was 22,000 +vat for t9 and 39,000 +vat for t8 blocks , internal wall blocks and thin joint mortar only. no delivery included.

.
 

Hi Sas,

I’ve worked out the calculations for myself and have come to the same conclusion. A square metre of Ytong wall is approximately €52. A square metre of Poroton wall is approximately €110. Given that the same U-Value is achieved by both blocks I am almost shocked to learn that Ecostein can provide Ytong blocks at literally half the price of FBT’s Poroton blocks. Also Sas, the Ytong 365’s are 2.4 times longer than the Poroton T9 equivalent so they can be layed faster saving on labour costs.

I’m a little excited now that I have found a product that is very competitively priced achieving an excellent, low energy, U-Value. What I will do is call Ecostein to confirm what we’ve been talking about and also to inquire about their 480mm block. Ecostein built a house in Killiney with these, see: [broken link removed] On their website they say that this 480mm block achieves a U-Value of 0.16 Correct me if I’m wrong, but is that almost a passive house (benchmark 0.15) achieved by just one wall?

Sas, thanks for your help. The information you provided through PM was invaluable. And to Bakerbhoy, don’t worry about the mistake.

Maggie
 
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Also Sas, the Ytong 365’s are 2.4 times longer than the Poroton T9 equivalent so they can be layed faster saving on labour costs.

This is not necessarily an advantage - have you confirmed this? Large blocks are harder, not easier, to lay, generally speaking.

But having said that, I know nothing about the Ytong method you describe. Hope it works out for you if you go with it.
 
hi everyone
firstly i am not an expert on eco building,but i am interested in protecting the environment we all live in.i had a two storey extension built last year plus i had the whole house insulated externally with paroc wool.i have been living in this house since december,so i know how it works.unfortunately i cannot tell you on this forum as i am taking my builder to court.however if you live anywhere near south county dublin you are welcome to come and see it and i can tell you how it really works!send me a pm if you are interested.

best of luck to all trying to build an eco friendly house,fair play to you