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thesis on external insulation (ewi)

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Comments

  • #62
    fclauson
    Registered Users, Registered Users 2 Posts: 1,691 ✭✭✭fclauson


    From the certs I have read a typical statement is
    The XXXXX external wall Insulation System can be designed to withstand the wind pressures (including suction) and thermal stresses in accordance with the Building Regulations 1997 to 2009. The design for wind loading on building greater than two stories should be checked by a chartered engineer in accordance with Eurocode 1 Actions on Structures: I.S EN 1991-1-4:2005. General Actions- Wind Actions. A general factor of safety of 1.5 is applied to design wind loads.


  • #63
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Well, fclausson, that's what it says on a tin of paint, so to speak .....
    A timber board can be nailed to the wall withstanding windforces.

    The question is: which EWIS is guaranteed to withstand the Irish weather for let's say 30 years? Or whatever number of years?

    The architect Maeckler calculates 20-30 years of lifetime for an external insulation with soft materials. Made in Germany.

    This means the price for it won't be recouped by energy saving.

    And a total of 20-30 years life time means plenty of repairs in the meantime. And a shoddy looking, patched up wall for maybe 10-20 years.

    Cork university hospital's aluminia fascade (EWIS) was 'guaranteed' for 50 years as far as I understand the suppliers home page, withstanding wind and rain. It didn't last 1 year. Propably killed by the sunshine.
    The last part wasn't up when the first problems arose.

    The external wall insulation in Orchard rd./Cork isn't up for 4 years. And is cracking, mould and algea or moss/lichen growing. The plugs visible through the plaster.
    Killed by botany.

    So these are two samples of larger projects I have seen failing here in Ireland within a very short time.

    There is surely a difference between the DIY insulation of certain cowboy builders (EWI=just buy EPS sheets and plug and glue them) and an EWIS, a system. But as said: we see both failing.

    On the continent they use specific EPS, enriched with biozides. Here it's standard EPS for the usual cowboys.
    Sure this sticks as well as long as the cheque isn't cashed. And maybe a bit more.
    But how much guarantee is on the job?
    Who guarantees how many years of a trouble free facade ?

    Once the algea/mould is growing within the insulation material it's destony is demolition, the dump. It would be to dangerous to wait until the next storm takes it down.
    But who takes waste EPS, enriched with biozides and glasfibre, paint and glue? And what would be put up instead?

    Guaranteed are a lot of costs.


  • #64
    BryanF
    Moderators, Home & Garden Moderators Posts: 10,146 Mod ✭✭✭✭BryanF


    Interesting discussion, has Maeckler's calculations been used in any peer reviewed studies?

    EWI with retro-fits: It's not always possible to dry-line and problems can occur where incorrect materials are specified in or outside.

    Would anyone like to discuss alternative materials lets stick with external solutions for now.
    • wood fibre
    • mineral wool
    • hemplime
    • biobased
    • anymore?
    pros and cons compared to polymer based EWI


    Irish conditions
    lifespan
    maintenance
    cost
    U-value v thickness


  • #65
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Try to contact Prof. Maeckler here

    http://www.chm.de/en/proj_overview.html

    An alternative to soft external materials could be 'hard' materials. For example foamed calcium based boards.

    The problem with non-mineralic products (organic materials) is their prone to rot.
    The theory behind sustainable building technology is that the structure has to last for many generations. And not that it turns into earth/compost before the investment is recovered.
    Our hemisphere is overloaded with buildings, Europe has more m2 available than needed. The population is declining, production methods are becoming more efficient, less space demanding.
    So we have the choice now not to build temporary shelters but sustainable structures. Let's do it.


  • #66
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    When looking at the issue of insulating one should have the long-term perspective in front.
    Not only the potential of saving on thermal energy but the future proveness of the structure has to be guaranteed.
    There are now new building regulations being prepared, the zero energy or near-zero energy building method is demanded.
    Here we don't look at the energy consumption on it's own, as a goal. But on the energy balance, energy consumed by the structure has to be generated by the structure as well.
    We can accept less thermal insulation of the fabric if we get more energy for 'free' to cover the demand.
    This means using solar energy via the sun facing surfaces. So ST energy at vertical surfaces (walls) and PV at the tilted surfaces, for example.

    ST can be integrated easily enough as a fascade system. Not only producing thermal energy but also protecting the structure against thermal losses. Similar to an EWI but working in both ways. This is an increase in efficiency of investment by some hundred percent when compared to a thermal insulation method on it's own !
    And PV can be used in similar ways. Building technology doesn't stop at wrapping.

    Making use of energetic potential is more than avoiding losses.


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  • #67
    BryanF
    Moderators, Home & Garden Moderators Posts: 10,146 Mod ✭✭✭✭BryanF


    A very interesting, high tech solution, but if I could just pick you up on some of your points
    • not all solutions must be totally organic, or better still, why not use them in-conjunction with a protective rainscreen (using your calcium boards) or lime plaster with good boots and hat design.
    • sustainable buildings are about using sustainable materials, as much as they are about the structure lasting for generations. If protected, non- mineral materials don't necessarily 'turn to compost', there's rammed earth buildings in France that have lasted two hundred years and cob buildings in Ireland that have lasted much longer. we must consider and look for solutions to use 'sustainable' renewable materials that we have in Ireland, especially given that we currently import so much of our materials
    • I'm in agreement with you on the EWI systems on the market, their embodied energy v lifespan v cost payback + lack of recyclability does not add up. But are you confusing structure with cladding, in my opinion we have gotten lazy here, in that, we don't want to do any maintenance externally, that would be necessary with many 'organic' solutions. there's timber clad buildings in Norway treated with wood preservative every five years, that have lasted hundreds of years
    • this 'zero carbon' buzz word seems to be focused on energy generation on site and not embodied energy for the construction/material process. I would much rather see a house built with low embodied energy materials and the owner pay into to a large group renewable scheme than have a 'zero' carbon label due to a costly energy generating wall system. I'm al for ST panels but they have their limits not to mention their lifespan and external climate conditions. build a house and build a renewable energy scheme but do them on their correct/suitable scale.
    • I disagree that "We can accept less thermal insulation of the fabric if we get more energy for 'free' to cover the demand" - consider the energy hierarchy, which simply put states: energy conservation before 'eco bling'. consideration of an EROEI calculation or an ROR/ ROI would confirm the above.
    I agree building technology doesn't stop at wrapping but Avoiding losses should be done first before Making use of energetic potential


  • #68
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    The Germans have mapped the wind load zones since a couple of years.
    Here is a sample from an EWIS manufacturer, page 3 and 4 :

    http://www.sto.com/webdocs/0101/ebook/sto_de/windlastnorm/index.html

    The publisher of the brochure doesn't recommend an EWIS resp. a fixing method for the olive zones at all. Zone 4 that is. Plugged and glued EWIS is only to be used for the zones 1-3. According to this publisher/manufacturer....

    The olive zones are the typical wind load zones for " All-Ireland ".

    If a world player for EWIS is strictly denying any product or installation recommendations for these wind forces - there is a reason I suppose !!

    Again my question to all who prescribe, sell or install EWIS in Ireland:

    To which wind forces are these EWIS guaranteed ?


  • #69
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    Source - Fraunhofer-Institute for Building Physics, Holzkirchen, Germany
    More than 500 million m² of External Thermal Insulation Composite Systems (ETICS) have been employed to insulate buildings in Germany since the early 1960s. In the last decade the application of ETICS became a popular measure to improve the energy performance and the weather resistance of façades in the building stock. Naturally this ra-ises questions about the durability of ETICS compared to other types of thermal insula-tion. Therefore a substantial number of multi-storey houses with ETICS have been inspec-ted several times since 1975 by the Fraunhofer Institute for Building Physics. The results of these repeated inspections may be summarized as follows: Damage or degradation of ETICS façades are no more frequent than with conventional rendered masonry walls. A slightly greater susceptibility of ETICS to microbial growth due to rain or condensation water can be detected. Costs and frequency of maintenance for ETICS are comparable to those of traditional wall structures. The same holds for other durability aspects.
    It is frequently supposed that the small thickness of the exterior plaster and a smooth insulation material as substrate are possible causes for damage from mechanical impact. Yet, even after several inspections, there were no signs of a special susceptibility to any real damage. On the contrary: conventionally constructed buildings in the immediate neighbourhood of the inspected objects frequently showed damage of the plaster due to deformation of the masonry.


  • #70
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Well, Sinnerboy, this opinion of Fraunhofer institut (building physics) is an opinion.
    Not more, not a scientific report, just an opinion

    Quote:
    Therefore a substantial number of multi-storey houses with ETICS have been inspec-ted several times since 1975 by the Fraunhofer Institute for Building Physics.

    It was achieved by visual inspections of about a dozen buildings ("substantial number"). And the costs of maintenance where pure guestimates. Numbers not available. None of the EWIS mentinioned where scrutinised, for example parts taken off and the material inspected, moisture meassured, microbiogical samples taken and researched.

    NONE of these houses where exposed to windforces as shown in the no-go map for external insulation as shown here on page 3 and 4 :

    http://www.sto.com/webdocs/0101/ebook/sto_de/windlastnorm/index.html


    Comparing bananas with spuds that is, Sinnerboy.

    So again my question:

    To what wind loads are the Irish installed EWIS guaranteed?
    And by whom? Based on what science?

    No EWIS manufacturer guarantees a simple plug and glue EWIS method for Irish conditions. Or coastal conditions around the Atlantic as such. But I'm open to be corrected.....

    That this Fraunhofer opinion ("report" would be the wrong term) was a favour done to someone is more than visible. Sentences like
    " On the contrary: conventionally constructed buildings in the immediate neighbourhood of the inspected objects frequently showed damage of the plaster due to deformation of the masonry. "

    are plain enough. Deformation of masonry, how that?
    And the costs of repairing a 15 mm cement plaster the same as repairing a plugged,glued, reinforced 80mm EPS fascade covered with expensive plaster being the same?

    Quote:
    Costs and frequency of maintenance for ETICS are comparable to those of traditional wall structures. The same holds for other durability aspects.


    These are phantasies of cowboy specifiers. No EWIS manufacturer would claim something like that.


    So again my questions:

    To what wind loads/weather exposure are the Irish installed EWIS guaranteed? For how long? What are the calculated lifetime costs?

    Any numbers?


  • #71
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    heinbloed wrote: »
    To what wind loads/weather exposure are the Irish installed EWIS guaranteed? For how long? What are the calculated lifetime costs? Any numbers?

    I am not a Structural Engineer so I can't be specific on this issue
    The design for wind loading on building greater than two stories should be checked by a chartered engineer in accordance with Eurocode 1 Actions on Structures: I.S EN 1991-1-4:2005. General Actions- Wind Actions. A general factor of safety of 1.5 is applied to design wind load

    This quote is lifted from one of the IAB certs for EWI . At the time of this post the are 14 systems listed here


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  • #72
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Looking at the fascades and their design has to include the doors and windows as well, as well all other elements. Frequenly EWIS is sharing the same wall as openings.
    EN 12207, EN 12208 and EN 12210 demands for exposed areas (like all of Ireland) specially designed fascade elements, doors and windows.

    So I wonder why the doors and windows specified in Ireland are designed to withstand high wind and rain loads but not the EWIS? Both are part of one and the same surface, the weakest link determines the strength.

    Is there an EN standard for EWIS concerning wind and rain loads ?

    Sto says yes, there is. But gives no answer on how to use their systems in Ireland. For a very good reason I say.

    Shouldn't this make us think twice ?

    And demand a full life time guarantee from the specifier, the manufacturer, the installer?

    And this life time guarantee would answer my question.....


  • #73
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    matoke.jpg?et=0KBu5WX8b8U8dwOQtnrfBg&nmid=0

    Made from green bananas and potatoes cooked with onion and tomatoes.


  • #74
    FarAdr
    Registered Users, Registered Users 2 Posts: 38 ✭FarAdr


    been in a meeting with a company there today, and they have in the past guaranteed their system for 40 years in the irish market, and they are sending me the wind load factors.
    The insulation comes from germany and has eu certification but they are waiting to get the irish cert almost two years.... its costing 35g and has been hald up by the iac board due to testing.
    The grand canal theatre and the opw building have been externally insualted with this company (without irish accreditation), and they have the maher hospital too...
    So theres your guarantee.....
    And they have approved installers.
    Also, the durability of the render has come into question in the past, and having seen a silicone based render there today, and it isn't that thick, I have to conclude that it is tough.


  • #75
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    Look here for Canadian research - over decades - to tall buildings ( 20+ stories ).

    Enter eifs ( in Canada they call it External Insulation Facing System )


  • #76
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    Look here for Canadian research - over decades - to tall buildings ( 20+ stories ).

    Enter eifs at the search ( in Canada they call it External Insulation Facing System )


  • #77
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Thanks for the links, Sinnerboy.
    Canada is a different climate (dryer) and the EWIS used there is of a different quality (better).

    I opened the first three links which popped up, here

    http://www.cmhc-schl.gc.ca/en/inpr/bude/himu/bebu/upload/Repair-to-Leaking-EIFS-in-a-Toronto-Condominium.pdf

    the EWIS failed after 5 years and was repaired (guarantee case?)and finished by aplying a rubber skin over the entire fascade. That was in 1992 and 1998 and the report from 2002....any news?

    The second report, here

    http://www.cmhc-schl.gc.ca/en/inpr/bude/himu/bebu/upload/EIFS-Cladding-and-Window-Replacement.pdf

    speaks about a total removing of the high quality EWIS(fixed with profiles, not just plug-and glue) which had turned into hazardous waste whilest the building was occupied.... They give no life time analysis here, how long it did take to rot down. Another 5 year project as before?



    The third report, here

    http://www.cmhc-schl.gc.ca/en/inpr/bude/himu/bebu/upload/Energy-Efficiency-Case-Study-Toronto.pdf


    concludes
    CONCLUSION
    The reduction in gas consumption
    due to improvements in the
    building envelope—installation
    of EIFS siding and sealing of door
    and window perimeters—was quite
    low (less than 5 per cent).The
    payback period for EIFS cladding, at
    147 years, was excessively long; this
    measure was thus not cost-effective
    from an energy savings perspective.


    So that's Canada. Payback in 147 years, sure someone will guarantee this(smiley).

    Google and you'll find more failures (concerning meassured real energy saving) than positive results.
    Not every EWIS project is a failure, but a lot are. If not most.

    Things look a bit better on the EU continent, I have some insider knowledge from there. But not much better.



    @ FarAdr :

    You said in your last post that you spoke to someone (or met him/her in a meeting) who claimed a 40 year guarantee on his EWIS.
    been in a meeting with a company there today, and they have in the past guaranteed their system for 40 years in the irish market, and they are sending me the wind load factors.

    The Irish windload factors are known, a reputeable company operating in Ireland would not have to search for these.
    A hint here :

    Met Éireann - The Irish Meteorological Service Online

    So just the guarantee that they make in writing, that would satisfy most potential clients and my demands.
    Would you mind to publish his name or to link references? Maybe by pm ?
    Such a claim I've never heard for Ireland or for a climate similar to the Irish, it would be a milestone in durability. A miracle !

    Thanks.


  • #78
    FarAdr
    Registered Users, Registered Users 2 Posts: 38 ✭FarAdr


    marmorit....


  • #79
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    HB - that 3 rd report does not state the thickness of insulation applied in 1995

    But the walls went from RSI 5.1 to 11.1 , which in U Values is 1.12 to 0.51.
    From that I estimate that 50mm of external insulation was applied. The bulk of the costs here were spent on labour and scaffolding . Pity.

    If 150mm - 200mm of insulation was used ( the amount anyone in Ireland should consider ) - a very different payback period would result .


  • #80
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Well, the thicker the material the more costly it becomes. Not just for the material but also for the fixing.
    Without additional work the passive gain of ST energy via windows is serriously influenced with thicker walls.
    The thicker the insulant the stiffer it has to be, movement during wind will squash it, move it. The more it moves the less it lasts. Esp. at corners the plaster will fail very quickly, microfissures occure and water will be blown into the material.
    So a standard glue-and-plug solution becomes unsustainable due to the reduced lifetime.
    A more rigid material would have to be used. With different fixing methods.
    Less insulating, heavier. More expensive.

    Therefore the rubber skin was applied to the Canadian building here:

    http://www.cmhc-schl.gc.ca/en/inpr/bude/himu/bebu/upload/Repair-to-Leaking-EIFS-in-a-Toronto-Condominium.pdf

    To allow for movements of the material and keeping it watertight.

    Another solution would be a plastifier added to the EPS, more expensive and may creating hazardous waste. The plaster would have to be flexible then as well. And of course biozides have to be added to kill all life forms in the damp and warm media.

    We can not use the old methods to tackle the problems caused by them. Something like that Einstein said.



    @ FarAdr:

    I've checked the British Marmorit home page as well as the German Knauf home page. There isn't a single mentioning about any guarantee. But maybe your 'meeting' contact might have a link ?

    The (wind) load bearing of the fascade has ALWAYS to be calculated. So Knauf's statement. I hope you do your calculations!
    As far as I know the installer is the one who has to give a guarantee concerning the lifetime. Unless there is an EWI System installed which is already covered under the manufacturer guarantee.
    But as said: there is nothing the like from the both companies on their home pages.

    As long as Knauf states that there has to be an individual loadbearing calculation to be done with each installation ( that's what it says in the "Bauamtliche Zulassung", the German official permit to sell and market the product)and nothing the like is/was done there is no come-back to them.
    This calculation must be done before the installation commences.
    Sticking to the contract means the installer must read AND understand it. And then follow the manual strictly.

    A (statical ?) civil engineer has to do that calculation, in my opinion, someone who is capeable and insured. This calculation also takes into account the background/existing wall, it's condition and the likely change undergoing in the future.

    For such a lifetime guarantee the Joe Average instaler (incl. myself) very likely hasn't the competence.

    The manufacturers know that. And let the idiots handle their materials and systems, they want to sell it after all. There is no manufacturer guarantee for cars concerning false handling of the object, if this helps to understand the situation.....
    Therefore no manufacturer lifetime guarantee is available for EWI(S).

    There are some EWIS manufacturers who give such lifetime guarantees, but look at the conditions. For example that coastal areas are excluded, wind class 4 on the German map.
    Here for example, the olive zones on page 3 and 4:

    http://www.sto.com/webdocs/0101/ebook/sto_de/windlastnorm/index.html

    As said: nothing the like I have found for the UK or Ireland. Or any country with such wind forces that is.

    But ask your contact and let us know. I might be wrong and just have overseen this lifetime guarantee.
    It would be interesting to get a statement from them, one that is water proof. So to speak (smiley).


  • #81
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Pushing up the post:

    FarAdr wrote on the 7th of April:
    been in a meeting with a company there today, and they have in the past guaranteed their system for 40 years in the irish market, and they are sending me the wind load factors.

    Tell us more about the guarantee for 40 years for the Irish market.
    I can't find anything.....


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  • #82
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Our feathered friends are showing a favour for the thin-plaster EWI type.
    The German press (the German association of private home builders (VBP) as well as the association of EWIS manufacturers) report problems with birds tackling the EWI.

    The feathered sub-tennants (?) are mainly wood peckers and blue tits. These birds take the EWI as a tree, the hollow sound and the good grip resembles that of rotten wood with bark on it. So they start to search for prey, pecking holes into the plaster.
    Once the first battallion discovers that there is nothing to find they leave the scene. But the demage done atracts insects afterwards, spiders and flying insects which choose the crevices as as a temporary shelter will be dicovered by the second batch of birds. And these think they have found a vertical feeding ground, increasing the holes and 'farming' their stock, so to speak.

    Here two articles (in German language) about the issue, first the home builders association:

    http://www.enbausa.de/daemmung-fassade/aktuelles/artikel/vpb-warnt-vor-attacken-durch-spechte-2126.html

    and then the EWIS manufacturer association:

    http://www.enbausa.de/aktuelles/artikel/spechte-ruinieren-fassaden-durch-hackversuche-364.html

    They found in the worst case 90 (!) wood pecker holes in 5m2 of EWIS.

    The recommendation of both are to use thick plastering (7mm embedded mesh plaster +3 mm coverage) to give strength to the EWIS.
    And bird shadows stickers (showing owls and storks) to chase away food searching smaller birds.
    Or cement fibre sheeting over the EWIS.

    See what your thin-plastered continental EWIS suppliers have to say about this.

    And important in monetarian terms: these atacks are a "natural disaster" in insurance terms. No guarantee from the EWIS manufacturer covers these, so the EWIS manufacturers say.
    And no home insurance as well, so I think.

    The ornothology laws of the EU forbid to disturb nesting sites. So once the birds decide to stay in the EWIS (for example behind a cladding) one has to wait for migration. Of the birds or the home owners, whoever is first (smiley).

    Try google for translation of the links above, ask your EWIS suppliers. In case there are still things to be translated, ask here.


  • #83
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    Some posts originally located in this thread were move to here


  • #84
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    Since FarAdr seems to have died (smiley) we keep the discussion going.
    Sinnerboy mentioned a Fraunhofer's study on EWIS ( post from 1.4.20011, 14.42h)
    it might be of interest that Fraunhofer Institut has just published a book, available via amazon.de ( http://www.amazon.de/Sch%C3%A4den-beim-energieeffizienten-Bauen-Bausachverst%C3%A4ndigen-Tag/dp/3816783686).

    Title: "Schaeden beim Energieeffizienten Bauen". Translated to " Demages with energy efficient building".
    It deals with problems faced by the building specialist when detailing energy efficient building methods.

    Check the book's title picture, showing a failed EWIS:

    http://www.amazon.de/gp/product/images/3816783686/ref=dp_image_0?ie=UTF8&n=299956&s=books

    I've seen a similar picture in Cork, see posts further above.

    Here my theory:

    The plugs are less flexible than the EPS, the EPS moves when exposed to the wind and the connection between plug and EPS fails. As well the plaster. Since the stiff plug cuts the soft EPS/insulant like a sawblade, forward and backward. On top of this comes moisture penetration, the wind blowing-in water at the fissures.

    Get your wind load calculations done, get them insured for the long-term.

    http://www.met.ie/climate-ireland/wind.asp


  • #85
    sinnerboy
    Closed Accounts Posts: 5,433 ✭✭✭sinnerboy


    looks like essential reading hb. is it available in English?


  • #86
    heinbloed
    Registered Users, Registered Users 2 Posts: 1,632 ✭✭✭heinbloed


    No, sorry, I don't think so.

    I'll order it and try to place essential informations here. If possible.


  • #87
    recedite
    Closed Accounts Posts: 13,989 ✭✭✭✭recedite


    manufan16 wrote: »
    hi FarAdr,

    They recommend the weber ext render but the feedback from my build being out to tender was some contracters proposing a 4inch block leaf on its side, tied to the EPS with a 25mm gap between EPS and Block then sand and cement finish rather than the render directly applied to the EPS.

    With the EPS protected behind 225mm of block, it should last 150 years no problem.
    The issue of wind loading transfers then to the stability of the outer wall, which is presumably why they want to lay blocks "on the flat".

    Another way of doing this might be to build a traditional cavity wall, but on account of the wide cavity, where wall ties are ineffective, but thicker walls instead.

    Anyone know whether two 150mm block walls separated by 200mm EPS filled cavity, no wall ties, would withstand Irish wind loads for a bungalow?
    The same using 225mm (block on the flat) for the outer leaf, for a 2 storey house?


  • #88
    woodk
    Closed Accounts Posts: 1 ✭woodk


    A note aside relating to external wall insulaiton systems (and stucco systems / EIFS / ETICS) - I'm an Engineer working in the area of Insurance Risk Management, Safety and Loss Control.

    Some conservative insurance companies will not insure externally insulated buildings where these use combustible insulation. This "combustible insulation" includes expanded or extruded polystyrene (irrespective of whether classed as fire retardant) and also polyurethane foam.

    Other insurers will write this business, but will classify the building as combustible. This could lead to a higher insurance premium for the life of the building.

    In general, use of FM or LPCB approved insulation is acceptable to insurers. This may include PIR foam insulation and rockwool / mineral fibre / glass fibre insulation. Combustible insulation that is entirely encased in concrete / concrete block is not normally an issue.

    My advice: If involved in any construction or external insulation projects using combustible insulation (particularly in a commercial environment), you should first discuss this with your Property Insurer or Insurance Broker (and get their response in writing).

    This is also good advice for any construction project. In general, Architects design buildings to life safety codes / building regulations that are principally concerned with ensuring nobody is injured or dies in a fire.

    Property Insurers don't want to have to pay out on a claim, so generally require higher standards than those for life protection (and most Architects don't take this into consideration in their designs).


  • #89
    sydthebeat
    Subscribers Posts: 42,862 ✭✭✭✭sydthebeat


    woodk, thanks for your input in this, its an invaluable viewpoint which you have.

    can i make some comments:

    1. the NSAI certification for phenolic insulation EWI was removed because of how this material preformed under real life situations. Are you saying that insurers would have insured EWI with this material while the NSAI was in place, and were refusing to insure PIR, PU or EPS systems?

    2. is no allowance made for the substructure of the building, which in EWI case is mostly 215 solid blockwork. why then does NSAI certification suggest EPS systems are suitable for use? surely they are testing for life spans of the product.


  • #90
    Danfogarty
    Registered Users, Registered Users 2 Posts: 2 ✭Danfogarty


    FarAdr wrote: »
    marmorit....

    Hi,

    I am currently researching a masters topic thesis and ive a keen interest into EWI i was wondering FarAdr if you could forward on your thesis to my so i can develop my own.

    regards

    dan


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