Key Post Poroton Blocks

re.poroton

Hi extopia !
18 working days incl. the lintels and the ring beam is very good.Congratulations!
The lintels should be embedded in a cut-off poroton block,again with the aid of %%WORD21%!.The professional way might be to but it slightly deeper than the edge of the blocks and than level the lintel up to the same hight as the blocks left and right-lm21 and a straight piece of timber.
That you are 150 blocks short is pretty bad.Check the delivery papers if anything went wrong.If you haven't counted the number of pallets than do it now.There are always the same number of blocks on each pallet exept for the last probably.Was your container full?If so than the brick kiln people might have used empty space in the second container-the other client!Talk to Wolfgang if you find so or to Fionula in the office,she is very effective and will find out if something went to the wrong site.
I took the render/plaster from FBT as well,it was not cheap compared to the ordinary stuff.But you could use the traditional lime plaster as well,the problem there would be to find some one who is able to apply the old technics.I certainly would not use the odd cement plaster because this would eliminate the ability of the poroton blocks(or any other material) to exchange the moisture of the air,its breath ability.After my first year in the new house I can recommend the plaster from FBT.
The plaster I used contains mineral fibers to give it some strength against cracking.I used it against Wolfgangs
advice without any reinforcing mesh over(combining) three different materials .Poroton,concrete(ring beam) and polystyrene
(extra insulation on the lintels)-no problem,no cracks.This plaster with it's fibers is of very good quality.
Plastering is a tough job ,if you can afford it get someone to do it.I did the plastering myself as well,first time in my life.The hardest part was to move the trestle,the site been uneven ,the rain pouring down sometimes and me wet all over.But it worked out fine.
I cladded the wall after the plaster was dry to keep the walls/plaster dry in driving rain. This in turn will prevent the wall to cool down once it evaporates the rain water.The temperature difference between a dry surface and a wet surface is about 6 degrees Celsius.
And there are a lot of rainy days (weeks!) down here.
But you can use this plaster also without any additional cladding,it is made for it.One hint:when plastering poroton than always spray or wipe the surface with a little bit of clean water,that avoids the "burning-off" of the lime meaning that the plaster has enough time to harden before it drys .
Breaking through the wall-ducts,cables-is simple.Mark the width of the duct plus a bit of lee on the wall and use a long drill bit working in a circle.Alternatively you could use a short drill bit and once you have drilled holes in a circle pattern you smash the block with a hammer and a chisel.To get all the way through the wall you need a longer piece of steel,a crowbar or a piece of steel pipe or the pick without it's handle.Use soft blows
once you are through the outer layer of the block.Work from both sides to keep the impact small.Use lm21 to fill the gaps after placing your duct.
 
Re: poroton

Thanks heinbloed,

I certainly will get a plasterer - have not got the gift myself! Know what you mean about working in the rain. Have had to graft it out in the downpours myself! Happy enough to have done the blockwork, so I can tell the grandchildren I built it myself!

Tips on ducting are appreciated, thanks.

Will talk to FBT about the amount of blocks delivered. I'm confident I got all the pallets that should have been in my order. I'd say about 10% of the original delivery was damaged, although I did reclaim some of these when a cut block was needed.

Another question... you can't hammer nails into these blocks so have you had any trouble installing kitchen units, for example, or anything else that needs fasteners? What about windows too?

Thanks
 
poroton

For smaller things you could use Pugs and screws.I glued plasterboard on the entire internal walls.The plasterboard can be used as a base for plugs and screws.My condensing boiler weighs 60 kg , no problem.

The windows where fixed with metal straps and screws by the window gang.I used polyurethane foam to fill the gap between the wall and frame.This gives plenty of hold.When the foam is cured you can cut of any surplus foam.On the outside you should -for energy conservation-
use a heavy layer of plaster or a strip of polystyrene board and glue it to the corner.You can plaster that over ,at door areas/jambs you could reinforce the polystyrene board with a reinforcing strip to protect the corner.Make that outer fixture of the frame wider than the inner fixture , mind the hinges.The reason is that the standard window frame is not very well insulating, in fact it will be a cold spot compared with the rest of the house.I have the problem with condensation on the frames and will tackle it before winter either by adding more plaster or fixing some sort of plastic rail on the outer frame.
Learning by doing!
For the very heavy items -outside timber cladding for example - you can use special plugs.They look like a perforated pipe and the screw/bolt is anchored with the aid of a synthetically cement from a tube.Looks like a silicon gun .The company Upat makes them or Fischer as well,but they are not cheap in the larger sizes.I got them from "Masonry Fixings" which has several outlets over the country.You could ask them to post a free catalog-I was baffled to see the choice of fixings that are available but can't be found in the builders and DIY shops.
 
Re: poroton

heinbloed,
Why the extra cladding on the exterior? Did you not trust the FBT "special" render? What kind of cladding did you use anyway? Not planning to do this myself, just hope the render is up to the job!
 
cladding

The plaster from FBT is o.k..But it will get wet when it rains and then the moisture will evaporate again when it drys.This effect will cause a cooling down of the wall/plaster surface of about 6 degrees Celsius below outside temperature.Since most of our precipitation comes in the form of water -usually combined with some wind- you will have two walls of your house during/after rain cooled down by 6 degrees Celsius.And this during the heating season costs money,the colder the outside the higher the demand for fuel.And most of our rain falls during the heating season.
(A quiet common and illogically way to plaster a wall in Ireland is "pebble dash" .It not only increases the surface-ruining the U-value calculations- but also attracts water a. because it takes more time to run off
and b. the cement/sand mixture in it sucks it up like a sponge )
One method to overcome this problem would be sealing of the outer surface of the house,making it waterproof.
But that would be a method that makes the walls "sick",moisture would accumulate in the walls,the thermal insulation would be effected,mould would grow,the place would become more ore less useless.
So the only passive solution is an aerated cladding,a cladding that keeps the rain away from the wall but allows the wall to give off moisture ("breathing").
The idea of a dry/warm wall is to increase its ability for moisture exchange with every layer of material -seen from the inside.So water that penetrates the wall -without regard from which side-will find it more difficult to get into the house than out of it.
Or vice versa , moisture from the inside of the house should travel to the outside .It should neither go back to the room nor should it be "stucked" in the wall.Any (aerated)cladding would enhance this effect by keeping the outer wall dry,because if it is saturated with water during rain any moisture exchange from the inside to the outside would be interrupted until the water concentration in the outside plaster goes back to normal/a lower concentration than on the inside.And we can have weeks of rain here,weeks of saturated walls.
This described situation is the same with any common wall material , be it concrete,brick,timber,straw bale etc..
More simply "explained":GORETEX,SYMPATEX.These fabrics allow the moisture to get out even if it is raining-that is what an aereated cladding is doing for a wall.
 
Re: >>Poroton Blocks

heinbloed,

Interested to reread this stuff about moisture travelling through the wall. Do you have any opinions on interior "cladding" (dry lining?) I have used interior plasterboard backed with styrofoam type insulation. These boards are fixed directly to the wall.

Also, we are about to do exterior plastering. I've ordered the MFL from FBT. But the existing house requires some exterior plaster also. The existing plaster on the house is very hard sand/cement (I was surprised to find it was not soft lime render.) Is this bad on a stone house? Not sure how "breathable" it is.

Hope I don't have to take it all off and re-render (this would damage the stonework significantly).
 
Re: >>Poroton Blocks

Hi extopia!
There was an earlier thread on AAM about insulation and foam backed plaster board .The ability of water to travel through walls must be considered with every building project carefully and calculated by the engineer.This calculation only would put you in the position to decide where to put the right material,be it plaster or insulation.To put up the right numbers one has to know whichever material has been used in the existing structure.The word "Stone" does not mean much in the records,there are too many different types of stone giving a wide area of speculation how much water/vapour actually can go through it.Basalt and sandstone for example.The first one would not allow a lot of water to penetrate it but sandstone would.Mortar and positioning of the stones(standing or laying) play an active role as well.
So my suggestion to you is to talk to an engineer who would investigate in the matter.As a rule of thumb you can consider that the ordinary plaster board used for ceilings and partition walls (grey) has a good ability to let water through, poroton has a better and the FBT plaster on the outside has even a better penetration ability.
Cement based plaster could seal the old wall,but that means that the moisture in the wall will accumulate until the wall is wet and cold.
If the outside plaster on the other hand is too weak than it would allow rain water to penetrate the wall.In the old times ,when houses where "punctured"
like an Emmental cheese (in the context of airing) and the open fire was running most of the time ,this wall trapped water could be taken up by the warm inside air and directed out.Either by the chimney or through other holes.But locking in the old wall from the outside with cement based plaster (and paint!)and from the inside with plastic in the form of EPS sheets will cause trouble.EPS boards do allow for a little moisture exchange-if in direct contact/glued to the wall-but not as much as for example lime based plaster.If the plasterboard backed EPS is only screwed or nailed to the mason wall than this "breathing" effect simply does not exist.The capillarity of the structure would be interrupted as it is in the "modern" cavity wall.
The simplest solution is to use aerated cladding on the outside.The cladding would allow the water to evaporate from the wall .But in that case I would go for the trouble and remove the old cement plaster , maybe replacing it with EPS sheets to give a layer of 10-20 cm strong.Covered with lime plaster and the cladding it would be a wall that has the benefits of heat storage and the U-value of a modern building,even better when you decide for the 20 cm insulation.
But it's all hard labour,so check with a qualified person at the site what is the best solution.
HB
 
Re: >>Poroton Blocks

A builder recently told me that he is putting Rockwool outside these now to improve the insulation values.
Any comments?
 
Re: >>Poroton Blocks

I am considering building with this material and am awaiting a quote from FBT. With such low U values Poroton blocks out perform most other building systems in terms of insulation. Why does he think this is necessary ?What does he suggest to clad outside the rockwool? Does the rockwool affect the breathability of the wall? Does anyone know of another source of these blocks as FBT appear expensive (4 yoyos per block 16 blocks per metre squared)
 
Re: >>Poroton Blocks

They only barely reach the present U-values that will be outdated in a few years.
In central Europe they insulate them on the outside to improve the U-values.
If you use Rockwool or Granitewool on the outside it is breathable.
You put a special breathable plaster on the outside of the rockwool.
I know a builder who brought similar blocks in from Poland.
He builds using these systems.
Where are you building?
Are you building yourself?
 
Re: >>Poroton Blocks

My father-in law (a stonemason)and myself will be doing the building in Cork. What kind of u value does the polish block have and what sizes do they come in? where is you friend building? seems to be very few poroton block fans in ireland at the moment
 
Re: >>Poroton Blocks

At the continent poroton blocks are usually insulated with sheets of expanded polystyrene, and in some cases with sheets of expanded polyurethane.I have never seen them done with glass wool or mineral wool.I might have simply overlooked that, but it seems to be of little use (the fibre insulation) if done to thin. A heavy thick layer of glass wool wouldn't have the holdfast, a simple suction effect on the side of the house away from the wind (leewards) would tear/suck the entire insulation incl. the plaster off the wall. As well any puncture in the water proof plaster can be penetrated by moisture, either from the outside or from the inside. Since glasswool is of a wick type structure it would suck up the water (unlike the PS sheets), making it heavy, badly insulating and unsafe. Poroton breathes and- if combined with a moisture uptaking substance- at the coldest spot(the outside of the wall) the damp would condense there, accumulate and become soggy, the entire wall would become wet.
If Leo has the necessarry national aprovals for the method described by him or any hint on them please let us know.
Check the home page of poroton ( the ww web) how the blocks can be insulated. But they are available in different qualitys, even a zero energy home can be build with them without any extra insulation.
The extra insulation is done mostly in places where the building conditions demand such a solution, for example in old buildings where the best available technology is applied when renovating. Or where the site demands keen planning concerning the distances from wall to site border/neighbouring structure.
Sometimes it is cheaper to extra insulate the poroton block instead of using a thicker type.
Check the web under "Wienerberger Ziegel" and see if you find an english page, most likely. "Poroton blocks" are not exactly the same as "hollow brick blocks". They have different physical values like load bearing, U-value etc.. Even though they look very much the same. Always insist on a certificate. And -of course - on the k-value. The best mono block available so far is the SX 11 with a k-value of 0.11W/mK. But there is a mixed material block new to the market which is a poroton block filled with Perlite, suitable for the Zero energy house without any extra insulation.
 
Re: >>Poroton Blocks

[broken link removed]

I think this link should answer most of your questions about the suitability of granitewool insulation for external cladding.
When Paroc is immersed in a bowl of water it takes in only 0.05% of its volume in water, compared with 30% for glasswool. Polystyrene takes in way more water than Paroc, If you pour water onto Paroc it runs off it like a plate.
The Polish blocks have the same U-value as the Poroton blocks 0.11W/mK.
Insulating Poroton Blocks with expanded polystyrene, and in some cases with sheets of expanded polyurethane stops them breathing and Paroc is a more natural product.
I am also looking at putting woodfibre boards (softboards impregnated with natural latex) outside the poroton blocks for a natural breathable house.
Paroc has the highest mass of all the fibrous insulations so it lets the heat from the midday sun through it at a very slow rate, it releases its heat slowly when it is needed the most around midnight.
Is Perlite the same as Light Weight Agregate? Can you send me this link?
 
Re: >>Poroton Blocks

Perlite is a mineral that is found around some vulcanos, the EU major supplier is from Greece. Here is a link to Wienerberger, propably the largest hollow brick/poroton manufacturer : [broken link removed]
" Schlagberg " from Germany (from where else -smiley) has patented the new block, try to check the web for them.The new "zero-energy-house" poroton brick with perlite filling has the trade name "F9".

Correction : Not the "F9" was used in the solar house but the "T8" , pictures are here : [broken link removed]
Usually the " solarserver " has some english pages, hopefully they translate this article as well.
 
Re: >>Poroton Blocks

Mike_C said:
I am considering building with this material and am awaiting a quote from FBT. With such low U values Poroton blocks out perform most other building systems in terms of insulation. Why does he think this is necessary ?What does he suggest to clad outside the rockwool? Does the rockwool affect the breathability of the wall? Does anyone know of another source of these blocks as FBT appear expensive (4 yoyos per block 16 blocks per metre squared)
Click to expand...

Hi Mike

We just imported a few truckloads of Poroton blocks from Poland for a Passive house we are building in Ballymore Eustace, it brings down the cost a lot especially when you pack up the truck with other lighter building materials. We need to use the outside insulation in order to increase the U-value to 0.15.
 
Re: Key Post: Poroton Blocks

Hi Viking House,
You said you got poroton blocks from Poland. Could you give the details of where you got them? What about certificates for the blocks? Who did you talk to about the build as Wolfgang FTB seems to good if you get stuck? Sorry about the 40 questions but I'm keen to build with these as well.
 
Re: Key Post: Poroton Blocks

Consistent breaching of posting guidelines and false representation.
Leo
 
Re: Key Post: Poroton Blocks

What kind of false representation was he making as I've talked to this guy about a building project?
 
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