Advice please : External Insulation versus ??

podgee

Hi guys

Apologies for starting another thread on External Insulation - but I'm afraid I got lost reading the Thesis thread on EWIS. I'm a layman looking for hopefully some sound advice.

We're considering insulation for our existing bungalow. We've looked at External Insulation and have been told that it's the rolls royce, the proper way to go etc. etc. Clearly, it's a lot more expensive than conventional methods. Is there ever a financial payback on it versus insulating internally ?

We went to the Ideal Homes exhibition and came across a company (I don't know if I'm allowed to name them here or not, so I won't), who have developed insulation for internal application that appears effectively to be a sandwich of different materials (apologies for the non technical language) with the service ducts included - I can't remember the exact contruction but it included foil backed insulation, osb and something else I can't remember. The guy I spoke to was insisting is was better etc than external insulation. We then spoke to an external insulation guy, who told us pretty much the exact opposite. Who to believe ! Any advice and apologies for the rambling post.

P

heinbloed

What is the target ? What is the status quo ?

hilloftara

i have gypthane slabs on my internal wall it is plaster foam and then a foil,when i do have the money i am going to get the external insulation, get the external insulation.how is your house insulated already

podgee

heinbloed wrote: »

What is the target ? What is the status quo ?

The target is a reasonably energy efficient house that doesn't cost the earth to heat. The status quo is a house that snow refuses to stick to the roof !

From the guys website that I referred to at the Ideal Homes Exhib - it says his product "is an insulated wall panel that basically consists of two layers of Rigid Insulation of varying thickness, one layer of 11mm Orientated Strand Board (OSB) and a 12.5 mm layer of plasterboard to the front."

It appears to consist of 60mm of insulation, 11mm of OSB, 25mm of insulation and 12mm of plasterboard.

Thanks
P

sydthebeat

podgee wrote: »

Hi guys

Apologies for starting another thread on External Insulation - but I'm afraid I got lost reading the Thesis thread on EWIS. I'm a layman looking for hopefully some sound advice.

We're considering insulation for our existing bungalow. We've looked at External Insulation and have been told that it's the rolls royce, the proper way to go etc. etc. Clearly, it's a lot more expensive than conventional methods. Is there ever a financial payback on it versus insulating internally ?

We went to the Ideal Homes exhibition and came across a company (I don't know if I'm allowed to name them here or not, so I won't), who have developed insulation for internal application that appears effectively to be a sandwich of different materials (apologies for the non technical language) with the service ducts included - I can't remember the exact contruction but it included foil backed insulation, osb and something else I can't remember. The guy I spoke to was insisting is was better etc than external insulation. We then spoke to an external insulation guy, who told us pretty much the exact opposite. Who to believe ! Any advice and apologies for the rambling post.

P

internal insulation will always be inferior to external because of the obvious problems of thermal bridging. Every time an internal floor or wall touches and external wall, a thermal bridge is formed. With external insulation, the insulation covers these points and thus provides a much better insulation envelope. Having insulation punctured all over with thermal bridges is akin to having dam with holes in it. The warmer the internal the quicker the heat will escape through these thermal bridges. Internal insulation also has the added hassle of having to move kitchen units, toilets, radiators etc off exterior walls in order to properly cover the internal wall space.

archtech

podgee wrote: »

The target is a reasonably energy efficient house that doesn't cost the earth to heat. The status quo is a house that snow refuses to stick to the roof !

From the guys website that I referred to at the Ideal Homes Exhib - it says his product "is an insulated wall panel that basically consists of two layers of Rigid Insulation of varying thickness, one layer of 11mm Orientated Strand Board (OSB) and a 12.5 mm layer of plasterboard to the front."

It appears to consist of 60mm of insulation, 11mm of OSB, 25mm of insulation and 12mm of plasterboard.

Thanks
P

If it were me I would go with external insulation. Advantages in your case include no disruption to the internal house during installation, no reduction in usable floor area, not altering of sockets lights etc. One major issue with the "insulated wall panel system" is that is could be prone to causing condensation. Certainly get some independent advice and analysis from a professional with experience in this ( there's one or two on here whom would help), if you do decide to go the second route.

In fact I would go as far as recommending that you would engage someone to advise and assist you in selecting the best route for you, whom is independent and isn't selling any particular product. An architectural technologist or technician /architect or engineer specialising in the area would be best.

heinbloed

Well, propably an energy advisor would have to have a look at your house.

Safing energy on the one side and spending it at the other doesn't make much economical sense.

The roof can't be insulated with external insulation unless a major overhaul is planned, so internal insulation is the usual option. If the roof space is to be habitated then it propably makes economical sense.
How much thermal energy is used at the moment per year and what is the target ?

In most cases the simple measures pay for themself. Like getting the heating system optimised. Draught proofing.

If the house is a good bet and well positioned (retail value) then it might make economical sense to invest in long-term solutions. Like perimeter insulation.
But be aware that this does not pay whilest living there for only a few more decades. Building quality with resale value costs energy, money that is.
It's the income's capeability to buy energy which determines it's value. In other words: money spend means energy spend.

So if there is no comfort problem (cold, drought, darkness) and no health and safety issue (mould and structural decay) insulation of an existing building doesn't make much sense.
Unless of course there is a long-term investment planned, something for future generations to be enjoyed. Dureability of the investment is the question then.

BryanF

podgee,
maybe give the forum some more info on your house, this will help to cut out a few of the options and assumptions

1. how old is the house?
2. what is the existing wall build up
3. is there any dampness/ condensation
4. what type of glazing have you
5. have you wall or window vents
6. how big is the floor area/ wall are to be covered
7. room in roof or insulated ceiling
8. are you planning any other works at the same time

the list could go on..

many of the insulation companies do not take proper account of your existing homes structure or other important considerations.

probably best to get some professional independent advice.

Carlow52

based on your direct quote and the power of Google, it was eASY to find the product in question, with the osb bOARD being the innovation in terms of addressing the need for fixing sockets etc as well as acting as a decent fix for the airtightness tape.

Whats not clear from the website is 3 things
1: how is the first layer fixed to the wall
2: how is second layer fixed to the OSB
3: how good ins the jointing between the sheets

It is indeed an interesting idea and the price point must be somewhere that make it more attractive for the punter to buy from them rather than buy the components from your local hardware.

Its a nice idea and thank for sharing it with us, in disguise:D

If u can find out how it is fixed then pls come back.

ps just see ur piece about the snow, thats a roof/ceiling job in the main

podgee

BryanF wrote: »

podgee,
maybe give the forum some more info on your house, this will help to cut out a few of the options and assumptions

1. how old is the house?
2. what is the existing wall build up
3. is there any dampness/ condensation
4. what type of glazing have you
5. have you wall or window vents
6. how big is the floor area/ wall are to be covered
7. room in roof or insulated ceiling
8. are you planning any other works at the same time

the list could go on..

many of the insulation companies do not take proper account of your existing homes structure or other important considerations.

probably best to get some professional independent advice.

The house was built in 1934 and has been dry lined down through the years. We are looking at a major refurb with the roof off and an new roof put on, new windows, some internal remodelling etc. The perimeter is roughly 60m in total, single storey. Currently don't have any issues with dampness or condensation. Architect is very pro the external insulation and really I'm trying to look for a second opinion I suppose on it. Is it worth it, are there any issues with using external insulation in Ireland etc. For instance, will the handlebars of a kids bike pierce the insulation if left up against the house (probably a thick question), how do we fix brackets for external lights, hanging baskets etc.

The proposal so far has been for an airtight house with MHRV installed. We intend being in the house for many years to come, so really want to make the right decision now, as opposed to having to revisit it again in 10 or 20 years time. We'll be putting in a new heating system, high efficiency condensing boiler together with UFH downstairs. The existing floor is being dug out and insulated above and beyond the latest specs etc. Our architect reckons we'll achieve an A3 rating (which I'm still trying to figure out if it's good or not!!).

Anyhow, all advice appreciated and apologies once again if the questions are utterly uneducated in their tone.

P

podgee

Carlow52 wrote: »

based on your direct quote and the power of Google, it was eASY to find the product in question, with the osb bOARD being the innovation in terms of addressing the need for fixing sockets etc as well as acting as a decent fix for the airtightness tape.

The power of Google never ceases to amaze.

P

MicktheMan

podgee wrote: »

The house was built in 1934 and has been dry lined down through the years. We are looking at a major refurb with the roof off and an new roof put on, new windows, some internal remodelling etc. The perimeter is roughly 60m in total, single storey. Currently don't have any issues with dampness or condensation. Architect is very pro the external insulation and really I'm trying to look for a second opinion I suppose on it. Is it worth it, are there any issues with using external insulation in Ireland etc. For instance, will the handlebars of a kids bike pierce the insulation if left up against the house (probably a thick question), how do we fix brackets for external lights, hanging baskets etc.

The proposal so far has been for an airtight house with MHRV installed. We intend being in the house for many years to come, so really want to make the right decision now, as opposed to having to revisit it again in 10 or 20 years time. We'll be putting in a new heating system, high efficiency condensing boiler together with UFH downstairs. The existing floor is being dug out and insulated above and beyond the latest specs etc. Our architect reckons we'll achieve an A3 rating (which I'm still trying to figure out if it's good or not!!).

Anyhow, all advice appreciated and apologies once again if the questions are utterly uneducated in their tone.

P

Given that you are undertaking such a major refurb, would you not consider going passive or at least making the airtightness, mvhr, walls, roof and windows/doors passive? If this was done then you should be close to A1. Do more research now so you dont regret it later.

damianoco

Hows things,

I am a civil engineer and i'm just getting into the insulation business myself. The External Insulation certainly looks like the best option. I have done alot of research into this and what i have found is it provides the best u value when compared to cavity fill and internal insulation. It protects your structure from the harsh elements we experience here, and provides a nice finish that will not require maintainence (painting etc..) for 20-25 years. The 1 draw back it because most or the renders are acrylic they will not take a water based paint. This means that you will have to fork out in the region of 150e per tin of paint, however this will again not need maintainence for a further 10 years.

All of the systems avilable under the SEAI home energy savings shemes are NSAI accredited, meaning they are all as good as each other. However whichever system you choose they are only as good as the installer. It is well worth asking the installer for refrences and going to see work he has previously completed! While going around to see the different systems i have seen some dreadful work (some of these contractors have been struck off the NSAI registered installers list) and some top notch work.

You can find info on the grants available (4000e for external wall) and registered installers available in your area on www.seai.ie

Hope this helps!

archtech

damianoco wrote: »

However whichever system you choose they are only as good as the installer.

Totally agree. was recently involved in a project where only one of the contractors knew what they were talking about, not only that they were also the cheapest, in the end and have done a good job, but then again they have been at EWI for 10 years or so. You can't beat experience.

heinbloed

Damianoco wrote:

However whichever system you choose they are only as good as the installer.

I disagree here. Any EWIS can only be as good/lasting as the load bearing capacity was calculated.
As long as the installer sticks to the civil engineer's specifications of material and workmanship he has done his job.
Here in Ireland we see windforces far beyond any guarantee given by any EWIS manufacturer - as far as I know.

So my question @ dimianoco:

Which lifetime do you ( "I am a civil engineer...") guarantee on your EWIS specifications? And which material and fixing method does this demand ?

See also this thread:

http://www.boards.ie/vbulletin/showthread.php?t=2056166150

The exposure of an EWIS to forces beyond their guarantee will nillify any guarantee.
See the windloads to be expected once in 50 years here:

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

Giving a guarantee on a work when it is clear (from the planning process onwards!) that the material's manufacturer guarantee DOES NOT cover the Irish weather conditions demands ingenius intellect. Or cowboys who give a damn.

sydthebeat

heinbloed,

Any system that is being installed has to have nsai certification.

Part of this certification is design in accordance with building regulations 1997 -2010

Part of the building regulations is structure, and part of teh structure regulations is wind loading.

The standards assessed as part of these regulations for wind loading is dealt with in chapter 1.1.3.7 of TGD A structure.
Ireland is divided into 3 wind zones. have a look yourself at page 6 and 7.

Where wind speeds are expected to exceed 44m/s then design must be in accordance with CP3: Chapter V: Part 2:1972 as amended in 1986 (this standard, while now withdrawn since this TGD was issued, has the same application field as european standard EN 1991-1-4 2005)
It should be noted that the revised updated Part A which is due for draft later this year will be using the revised values of fundamental basic wind velocity obtained from Figure NA.1 of the National Annex to I.S. EN 1991-1-4 2005

So, in my opinion, that means that if the product is for use in any area in ireland, it must be show to be able to withstand wind loads in accordance with CP3: Chapter V: Part 2:1972 as amended in 1986. Thats what my understanding is anyway and id be very surprised if its otherwise, because thats what the regs state!

Any future NSAI certs for EWI, once the new TGD is published, all must be in accordance EN 1991-1-4 2005.


If you check some of the NSAI certs for EWI you will see that they claim to be certified in accordance with the regs 1997 -2010 and any use of the product outside of this scope should be checked by a chartered engineer in accordance with EN 1991-1-4 2005


if you have more questions about the NSAI use of calibrated wind loads please check here
you can see that there has been major study done in relation to wind loads by our certifying body.

heinbloed

Thanks!



There is the EWIS -the SYSTEM- and there is EWI. Two different things.

EWI is not patentable, it is not a system but a method. And therefore needs no NSAI agreement.

So about the EWIS:

I still haven't seen an EWIS (the complete system) which is designed to withstand Irish conditions.
No manufacturer offers anything like a lifetime guarantee for lets say 20 or X-years. It takes usually about 30 years for a pay-back, an ammortisation. And a few years extra to cover demolition and disposal.

So please: the EWIS which is guaranteed ( by who ever) to last for a certain life time.
This is all I'm looking for.

And if there is nothing the like ( I fear so) then who guarantees that the installed EWIS will last for a certain time?
What is important to know to calculate if energy is wasted or saved when opting for it.

Certainly not the NSAI, the state.

If a manufacturer states that his product bears a certain label, is aproved by a certain body: that is no answer to my question.

It is - as far as I know - the specifier who has to give a lifetime guarantee.
If the weary consumer dears to ask. And isn't baffled by stamps or seals or other advertising material.

That a new car has a legal guarantee of 2 years (for the consumer) doesn't mean that the manufacturer or seller (the specifier) can't give 3 or 5 years.
This is frequently done as we know.

If a bucket of wall paint bears an NSAI label - would it last for decades? Is there any lifetime guarantee included in an NSAI agreement? No, there isn't.

And I don't see this done with EWIS in Ireland.Neither by the state(NSAI) or by a specifier (civil engineer). For a very good reason I'd say.

So this fact leaves the consumer with the question:

If the EWIS fails after 3 or 10 years, needs repairing or replacement, who will have to pay?
And if it's installation doesn't save the thermal energy calculated - who will fork out?
And if damages beyond are occuring (damp walls, injured people) - who forks out, who is legally responsible for how long after installation?


On the EU continent such life time and -performance guarantees for EWIS are available, are part of the contract. 50 or 60 years in Austria in the past, for example from sto. Reduced to 30 years now !

But nothing the like in Ireland - as far as I know.

Maybe some professionals can shed a light?

sydthebeat

:rolleyes:

read the certs, the guarantee is located within.

heinbloed

read the certs, the guarantee is located within.

Who's cert?

I've checked Baumit (NSAI certified) and couldn't find anything......except the 2 references to the German "bauamtliche Zulassung" - the German cert that is.
And there - in the German cert- not 1 word about a guarantee. Except that the loadbearing calculation (which includes the wind loads) must be done with each individual project. And guaranteed by the specifier... but that is consumer law.

So this cert from Baumit contradicts the NSAI. Well, vice versa that is. Since the German cert was there first and NSAI refers to it. Without understanding a word of it - it seems to me.

So again: what guarantee is given to the comsumer when deciding for any EWIS in Ireland? By who?

A professional would post a link from his reference material and that's the end of the discussion, question answered.

damianoco

As long as the installer sticks to the civil engineer's specifications of material and workmanship he has done his job

.

I completely agree that if the installer sticks to the strict guidelines set out by the SEAI, NSAI and manufacturer/supplier then he has done his job to the best of his ability. In reality alot of contractors are in this game for the quick buck, and as a result are carrying out bad work. They will continue to do so as long as the demand is there. Recently NSAI have stricken off quite a number of contractors. While carrying out surveys with a gas instalation company we noticed that more than 1 contractor had not removed and reset the gas box and as a result the box couldnt be taken off in an emergency shut off situation or for service. A letter of complaint had to be sent to NSAI and is currently under investigation. This issue arises again with ESB boxes etc...

So my question @ dimianoco:

Which lifetime do you ( "I am a civil engineer...") guarantee on your EWIS specifications? And which material and fixing method does this demand ?

I am only in the preliminary stages of setting up and i have yet to agree a guarantee length with my partner. The system i will be using uses aeroboard bonded to the external wall by means of expanded foam and mechanical mushroom fittings drilled 35-40mm into the wall. It is a requirement by NSAI that a test be carried out and photographed piror to insulating on every project. The manufacturer offers a 20year guarantee on colour, aeroboard offers a guarantee on the high density expanded polyurethane(i'll check out how many years and get back to you) and the supplier (a very well known name in the irish building industry for over 50 years) offers 15 years on the system as a whole. I expect to be offering in the region of a 20 year guarantee.

heinbloed

Thanks, at least some numbers.

Now: all guarantees are given under certain conditions which must be met.

So it would be interesting to see them. As in my previous post stated most EWIS manufactured and sold on the EU continent are only covered if the individual project had been ascertained, the (wind-) loads been calculated.
And the EWIS been used accordingly.

I have seen now - so far- no guarantee from any manufacturer which is selling EWIS on the EU continent covering the wind loads shown on the Meteireann map ( http://www.met.ie/climate-ireland/wind.asp).

Whilest there are methods to use EWI in Ireland I have my doubts if the standard glue-and-plug-and-mesh-plaster method (the cheapest way!) works, any long term guarantee which allows to recover the investment is not available to me.

So if there is a link (www.) showing the conditions which have to be met to get covered by a life time guarantee please let me know, maybe via a private message ?

Fordpefect

archtech wrote: »

Totally agree. was recently involved in a project where only one of the contractors knew what they were talking about, not only that they were also the cheapest, in the end and have done a good job, but then again they have been at EWI for 10 years or so. You can't beat experience.

can you send me the name of that contractor, my folks are looking to get it one, I have seen a few jobs going on that do not look that great, in regards to waste pipes ETC

therightangle

heinbloed wrote: »

So if there is a link (www.) showing the conditions which have to be met to get covered by a life time guarantee please let me know, maybe via a private message ?

Please keep this thread going and in public - if there are issues regarding the finer details of consumer protection in EWIS, I would like to hear them.

muffler

therightangle wrote: »

Please keep this thread going and in public - if there are issues regarding the finer details of consumer protection in EWIS, I would like to hear them.

Not really what this forum is for.

therightangle

muffler wrote: »

Not really what this forum is for.

I would like to hear of any reasons not to go with EWIS for a newbuild - is this not okay for the forum?

muffler

therightangle wrote: »

I would like to hear of any reasons not to go with EWIS for a newbuild - is this not okay for the forum?

No problem with that.

BryanF

therightangle wrote: »

I would like to hear of any reasons not to go with EWIS for a newbuild - is this not okay for the forum?

Therightangle, your asking for the pros and cons of EWIS? may I ask what you preferred wall construction is or what have you discounted to date?

Cons:
there's much higher embodied energy if you go for an EPS and block build over timber frame with cellulose or hemp or similar.. is that the type of info your looking for?
Heinbloed is adamant that EWIS do not have the correct wind loading factors for our gusty Irish climate.
I would suggest the biggest problem with the systems/ product is the generally poor specification of the right product for a given situation, and getting the right installer to do the job correctly... plus the interfaces and crap detailing still being allowed by many self-builders/home owners many through ignorance and corner cutting.(this is not particular to EWI but wide spread as quality suffers due to budget constraints BTW)

Pros
IMO people are looking at EWI, as methods of construction improve and we become less inclined to worry about dampness in the wall structure and the need for a cavity. (also because the cavity is getting up over 200mm wide to accommodate the amount of insulation required!)
EWI tacked on to the outside is better than drylining from a thermal mass, and more importantly a thermal bridge perspective. But this all goes back to why your going for block construction....

hope this helps, as a matter of interest what is your architect recommending?

sas

BryanF wrote: »

But this all goes back to why your going for block construction....

hope this helps, as a matter of interest what is your architect recommending?

With respect, this thread is about the pros and cons of EWI.

It would serve us all better if this thread avoids the ongoing debate on block construction vs the rest.

BryanF

sas wrote: »

With respect, this thread is about the pros and cons of EWI.

It would serve us all better if this thread avoids the ongoing debate on block construction vs the rest.

Noted.

but a holistic approach must be taken when discussing EWI... its not just hanging there un-supported:D

sas

BryanF wrote: »

Noted.

but a holistic approach must be taken when discussing EWI... its not just hanging there un-supported:D

Yes, but I'm one of those people that believes the idea of externally insulating anything other than block makes no sense whatsoever.

When I hear EWI, I picture blocks with oil based insulation stuck to them.

BryanF

sas wrote: »

Yes, but I'm one of those people that believes the idea of externally insulating anything other than block makes no sense whatsoever.

When I hear EWI, I picture blocks with oil based insulation stuck to them.

As do I

heinbloed

The previous two post read:

Quote:
Originally Posted by sas
Yes, but I'm one of those people that believes the idea of externally insulating anything other than block makes no sense whatsoever.

When I hear EWI, I picture blocks with oil based insulation stuck to them.

As do I

There are many more choices out there, alas not cheaper than EPS. Mineral based foam or fibre insulation, vacuum panels, sheep- and cellulose wool and so on.

The cheapest method is usually not the longest lasting. And an ammortisation must be - unless one wants to waste energy.

If a method is described as "energy saving" the ammortisation of the investment has to be met. Plus some energy savings to follow the ammortisation, of course.
The sum would result in a guarantee of X-years life time.

I still haven't found an EWIS sold or installed in Ireland with any life time guaranteed by the manufacturer.
The only life time guarantees I have seen so far are the EU continental ones. But these continental EWIS (the very same as sold in Ireland/UK as well!) are excluding wind forces as seen on the official Irish weather map.

And Irish specifiers are very tight-lipped when it comes to their own guarantee. See this thread.

Like selling pain killers to fight cholera.

heinbloed

There is British Standard 7543:2003 for which a guarantee can be given by the installer or manufacturer.

I came across an EWIS used for containers, see

http://www.extraspace.ie/wp-content/uploads/2010/10/Irish-Agrement-Certificate.pdf

There a steel covered EPS (wall-) system is shown, certified to BS 7543:2003

And we read:

3.3 WIND LOAD
Buildings designed using the Extraspace Advance System will have adequate resistance to wind load in areas within the 25m/s maximum 60 minute wind speed contour (as shown in Diagram 15A of TGD to Part A of the Building Regulations 1997 to 2007). For very exposed sites on hills above the general level of the surrounding terrain, the system can be specifically designed to meet the requirements as defined in BS 6399-2:1997. The system can be designed to be used in all locations in Ireland.

(Enhancement by me)

Can be designed.... means it isn't fit (certified!) for the Irish climate as shown in the certificate. But can be made so.

So an EWI or EWIS based on EPS and covered with steel as shown above isn't guaranteed under BS7543:2003 for Irish wind- and water loads. Needs further reinforcement to have any life time expectation according to BS.

And a plaster/plastic render covered EPS wall system? Installed in Ireland? Any guarantee or mentioning of a designed lifetime?

Forget it.

As long as the taxpayer can be milked, what does the consumer bother about something stupid like energy saving or intelligent investment anyhow......


Or is there a BS7543:2003 mentioned in any NSAI certificate handed out for an EWIS?

It seems to me that any NSAI certified container is a better long-term investment to live in than an Irish house equipped with an NSAI certified EWIS ......

heinbloed

The only life time guarantee demanded for subsidised energy 'saving' meassures (for material and workmanship) seems to be demanded when retrofitting ST energy. 5 years if the taxpayer has to fork out.

See

http://www.seai.ie/Grants/Better_energy_homes/Code_of_Practice_and_Technical_Specification.pdf

For guarantee demands check the end of the document, last two or three pages.

And ST isn't saving any energy at all.....but a 5 year warranty/guarantee has to come with it. Absurd.

No such guarantee is demanded for the rest of the taxpayer drainage program, like boilers and insulation. Take it and keep it, no matter how long it performs or not.

BryanF

Just had a lenghty chat with an installer who offers PIR, EPS and mineral wool EWI. Reading between the lines, he was saying, because certain areas of the installation process are not required/specified by the SEAI grant system, they do not get done adequately! (window reveals, Eaves etc). Also, although mineral wool is 'similarly' priced, it is not preferred by installer's because if it gets wet (before rendering) the rendering process(calcium silica type render with plastic mesh) can not take place until it dry's out. basically, the breathable EWI option requires covering during the process and is therefore not preferred by installers. IMO SEAI need to re look at how these grants are handed out, it all comes back to self-certification. while there are lots of good installers out there, IMHO they are going to do what's easiest for them and not always whats best for the building, through either ignorance (interstitial condensation) or hassle issues. I'm biased here, but there are lots of reasons why an arch should be employed to provide spec and details, and who can supervise and advise the client independently to the contractor.

sas

BryanF wrote: »

... while there are lots of good installers out there, IMHO they are going to do what's easiest for them and not always whats best for the building

Your definition of good and mine clearly differs then! I promise I'll stop taking issue with your posts BryanF

I will speak to my experience with EWI companies. I went into detail with 3 companies for my own home. All looked ok until I got closer to being ready to start.

Company A fell to the side when they sent me to see a site by a preferred installer. It was rough shall we say. The salesman was fully aware that I am shooting for certified passive and recommended that I visit this site. He got an earful off me later. I also learned afterwards that their "training" consisted of 1 day with half of it being on site safety and u-value etc and the rest being a demonstration of the materials i.e. no trainee touched any EWI materials while on training. I learned this through a friend of mine who did the training with the intention of doing his own home. This is actually where it gets worse. The company in question was fully aware that my friend was only their for his own home and had NO construction background or experience. A few weeks later he got a phone call from the company wondering if he'd be prepared to take on a job for them because they had no installer in that area!

Company B fell by the way side based on their guarantee. They have a 10 year insurance backed guarantee on their system. The problem is that the insurance mandates that the IAB cert detailing be followed. As passive details require good thermal detailing and the IAB cert doesn't (basically), they wouldn't give me the guarantee using details outside the cert. This is all well and good but they'd known for months that the detailing was different. It looks like they basically were hoping I'd stop asking questions. I only ever got to speak to their salesman, their technical people showed little interest. Plus the installer I intended using turned out to be not up to the job, much to his protests otherwise!

Company C therefore were a breath of fresh air. I spoke to their salesman once. A few days later the salesman, their technical manager from dublin and a recommended installer were on site to see what was involved. They told me that certain things I'd planned on doing where out (and with good explanations why) and gave me details that they'd be happy to do that give me what I was looking for. Once my windows were installed they (all 3 of them) came on site to inspect the installation detail. This was where they really came into their own because they pointed out that the end caps for my aluminium cills were not the recommended type for EWI. Since then I've been at war with my window company about the end caps but that's for another day. I will underline that I've paid no deposit to this company yet and they are still being very responsive. They are a very large german company. They are costing me more on the job than some of the other quotes. I am more than happy to pay it however based on what I've experience so far. I will report back on how the job actually goes in a few months time. The warranty they offer is less than inspiring however, 5 years materials only. I do however need to trust in NSAI certification (to a certain extent).

I have no intention of telling anyone who A and B are, either by PM or otherwise. People must do their own due diligence. All 3 are IAB certified however.

There will be plenty who think I am foolish ( saved you some typing there Heinbloed ) and truth be told I'm not convinced that's not true. I am however committed to this path as I've block on the flat and no other option now. The only safe option in the majority of Irish peoples eyes (and I will include construction profressionals of all types) is our traditional partial fill cavity. I wouldn't be uncomfortable suggesting that even amongst our small group of moderators there is a big difference of opinion on what is the best option. If I was starting again a wide cavity would be damn attractive.

I've rambled on for long enough...

heinbloed

Thanks for this informative post, sas!

The longer you type (or "ramble") the more information is revealed. Be it pure technical or emotional, it all helps to make decisions.

The extra wide cavity (

If I was starting again a wide cavity would be damn attractive.

) is actually a preferred method by many architects and engineers when doing EWIS on commercial structures.

A fibre cement board or metal sheeting or the like can be installed above the EWI, this would then create the ventilated cavity, the protective layer for the insulant.

In Cork the University Hospital used metal sheeting which warps now, it looks awefull and maybe the sealing between the sheet's contacts is effected as well. Some is dangling out. Risk of wind and water ingress! But this seems to be a material supplier's fault, I have seen it done sucessfully elsewhere.

In case the existing EWIS fails on your own walls in a few decades you still have a solid wall which can be used as a fixture for protective boards/sheeting, a base to work on. Others are less lucky, having opted for a lightweight wall with little extra loadbearing and fixing methods to be added.

Good luck with your building !

BryanF

good stuff, ramble away.:)

would company C begin with a W?

When I started the discussion with this particular installer, I was particularly interested in how the insurance system works, with an interest in a particular major mineral wool product (which can be installed as part of the EWIS, I was interested in trying to get a breathable EWIS). when i rang them, they insisted that the installer would agree details on site (they did not provide typical details) and the installer would give the required 10 year guarantee under the nasi certification.

I too am concerned by a lack of knowledge in thermal bridge free detailing and whether an EWIS provider/installer will certify non-standard (passive standard) details.

SAS Please send me your preferred company name and tell us more about the alu cill pitfalls

sydthebeat

BryanF wrote: »

good stuff, ramble away.:)

would company C begin with a W?

When I started the discussion with this particular installer, I was particularly interested in how the insurance system works, with an interest in a particular major mineral wool product (which can be installed as part of the EWIS, I was interested in trying to get a breathable EWIS). when i rang them, they insisted that the installer would agree details on site (they did not provide typical details) and the installer would give the required 10 year guarantee under the nasi certification.

I too am concerned by a lack of knowledge in thermal bridge free detailing and whether an EWIS provider/installer will certify non-standard (passive standard) details.

SAS Please send me your preferred company name and tell us more about the alu cill pitfalls

Bryan, why would you be looking at a breathable EWIS... wouldnt the render be considered very much unbreathable??

sas

BryanF wrote: »

good stuff, ramble away.:)

would company C begin with a W?

SAS Please send me your preferred company name and tell us more about the
alu cill pitfalls

"W" didn't even make the 3. At the time they were all metal profiles and not interested in doing PH detailing so I never went any further with them.

PM away.

For the rest of you in the industry....

Company C
- 1 syllable
- Sounds like "Snow".


On the alu cills I intend doing a detailed write up for the forum on this, pictures etc. To say I'm p***ed off over this is the understatement of the century! I'd like the good people here to be well informed and learn from those of us currently taking the plunge. Give me a few days.

BryanF

sydthebeat wrote: »

Bryan, why would you be looking at a breathable EWIS... wouldnt the render be considered very much unbreathable??

well, I'm finding that out slowly but surely... I'm still convinced there must be a render system that can be made of a silca/calcium basically 'lime' type structure. (just like for those who must dryline) but I clearly have lots more research to do..

the ridged mineral wool board or timber fibre board works (used mainly on old pre conc block walls), and I know you can go for a rainscreen, but can an EWIS provide a breathable render finish?....

sydthebeat

BryanF wrote: »

well, I'm finding that out slowly but surely... I'm still convinced there must be a render system that can be made of a silca/calcium basically 'lime' type structure. (just like for those who must dryline) but I clearly have lots more research to do..

the ridged mineral wool board or timber fibre board works (used mainly on old pre conc block walls), and I know you can go for a rainscreen, but can an EWIS provide a breathable render finish?....

I know of a single skin ICF system that uses a 50mm sprayed on concrete finish as its exterior. Perhaps a lime based aggregate could be applied in this manner to a mesh on the EWI?
I know lime is an incredible difficult aggregate to 'get right' on site...

BryanF

sydthebeat wrote: »

I know of a single skin ICF system that uses a 50mm sprayed on concrete finish as its exterior. Perhaps a lime based aggregate could be applied in this manner to a mesh on the EWI?
I know lime is an incredible difficult aggregate to 'get right' on site...

ah ye, we could start talking about Hemplime and other solutions, but for now

can an EWIS can provide a breathable render solution? its worth an ask:)

heinbloed

BryanF wrote:

the ridged mineral wool board or timber fibre board works (used mainly on old pre conc block walls), and I know you can go for a rainscreen, but can an EWIS provide a breathable render finish?....

Banned now in many countries, USA, Canada etc...

See also page 473 on this mighty document:

http://www.byg.dtu.dk/upload/institutter/byg/publications/rapporter/byg-r189i.pdf

and

http://www.ibp.fraunhofer.de/Images/K%C3%BCnzel_2008_Influence%20of%20rain%20water%20leakage%20on%20the%20hygrothermal%20performance_tcm45-86537.pdf

The same goes for any wicking material. Disaster is the consequence.

heinbloed

Here a German text, note the picture "Abbildung 7 " on page 42:

http://www.ibp.fraunhofer.de/Images/K%C3%BCnzel_2010_Au%C3%9Fend%C3%A4mmung-bei-Bestandsbauten_tcm45-86532.pdf

The copied document has a bad resolution, I have the printed version here, so I explain:
The picture shows an old EWIS (beginning of the 90's) on a test building at the Fraunhofer IBP. The EWIS had been taken off to meassure the moisture content in the EPS EWIS.
There are 2 windows at ground floor level with cills and roll-shutters, these show serious water accumulation in the EPS, 4%-10% by volume directly under the cills and above the roll-shutter.

The thermal conductivity (local U-value) is increased by 20%. The moisture storage capacity of the wall can become exhausted with such a water content, damp walls would be the consequence.

aghbren

rockwool and silicate render?

BryanF

heinbloed wrote: »

BryanF wrote:



Banned now in many countries, USA, Canada etc...

See also page 473 on this mighty document:

http://www.byg.dtu.dk/upload/institutter/byg/publications/rapporter/byg-r189i.pdf

and

http://www.ibp.fraunhofer.de/Images/K%C3%BCnzel_2008_Influence%20of%20rain%20water%20leakage%20on%20the%20hygrothermal%20performance_tcm45-86537.pdf

The same goes for any wicking material. Disaster is the consequence.

so what recommendations are there for mineral wool and a mineral render that will retain a degree of breathability of old walls in a retro-fit. its all about some level of vapour permeability(sweating) being retained.

Thanks heinbloed
I read the conclusion and looked at the parameters of Zirkelbach's study, it suggests that yes mineral wool absorbs moisture but it also dries out and regains its original properties. the title 'suggests a revision of durability test' thats all.
then the second paper Kunzel (which talks about timber frame issues in the 90's in US) says "Europe ETICS are applied for about 50 years. More than 40 million square meters of ETICS are installed on new and existing buildings every year in Germany and severe problems or damage cases have been rare" [Künzel et al. 2006]. and goes on to state in the conclusion that "The normal ETICS composed of vapour retarding EPS insulation slabs, cannot provide much drying towards the exterior and may therefore be responsible in part for increasing the risk of moisture damage for the underlying substrate", it then recommends replacing eps with mineral wool + of course, proper detailing to stop water ingress. interesting they do mention a drainage plane between the insulation and wall.

heinbloed

The mineral wool can take up water as we know. And this water can freeze. Causing an abnormal heaving, weakening the structure.
Once frozen the moisture still penetrating the wool from the house will increase the thickness of the frozen lump/layer. Adding to weight and volume.

Here wufi would be the only answer, with ample of leeway for frost situations, clear nights and high moisture loads.

Problematic is future treatment of the mineral rendered walls, once painted with a diffusion tight paint the moisture will be locked in for good.

(Mineral and plastic) renders allow water to condense at the outer surface, thawing of ice and dewing of airborne moisture will happen both on their surface. Whilest the render is prepared to survive this the wool can not get rid of the internal moisture if covered with a layer of ice (frozen render).

And with temperatures deep enough to freeze the entire layer of render the interstitial moisture can form ice within the wool, see above and also the links.

These are theoretical problems which had rarely been seen in situ. But they do exist.

A breathable, thick render is the remedy. And of course the avoidance of ice formation on the external surface. For example with the aid of cladding (rain, dew), a wide roof overlapping the wall (cold sky).

The thickness of the render increases it's resistance to freezing, simply because of it's thermal storage capacity. But this results only in a delay, it won't be a total protection.

The thinner the render,the less thermal storage capacity it has and the less breathable it is the higher the risk of freezing temperature within it.
1 Kh (Kelvinhour)of difference means a lot here when delaying the freezing.
Frozen renders do not allow water to pass through it, first they have to thaw themself.
With longterm freezing in very dry air (for example seen with continental winters) the ice within the render can dry as well. Freeze drying it is called.

The issue is complex, so better use wufi or some other simulation program.
And play safe, as said: protective meassures are not difficult to install. But have their limits as well.

heinbloed

See:

http://www.state.mn.us/mn/externalDocs/Commerce/Stucco_Study_111202035327_Stucco.pdf

Read case 10 for concrete walls equipped with EPS.

heinbloed

Since there is a good reason why hollow block concrete walls fail and cavity walls where invented the question arises what driving rain loads EWI can take resp. to what load it is exposed to.
So my question to our weather specialists and civil engineers and those who have some sources of knowledge:

What are the 'driving rain loads' in Ireland?

From my own observations these are considerable higher compared to the EU continent, more wind and more rain for sure.
Kuenzel mentions them here in this document, chapter 3.1, see also table1 for comparrissons:

http://www.ibp.fraunhofer.de/Images/K%C3%BCnzel_2008_Simulating-Water-Leaks-External-Walls_tcm45-86534.pdf

Whilest Kuenzel publishes the anual loads there is no reference to peak loads, to liters per hour during a specific season (winter, summer).

Are the 'test regimes' of IAB and NSAI taking into account the driving rain loads? Based on which data? With how much of leeway, limits, peak loads?


Is any Irish-certified EWIS manufacturer guaranteeing his products for the Irish driving rain loads? Any links? I couldn't find any data on guarantees from them at all, maybe I've checked in the wrong corner....


Thanks.

heinbloed

Some pictures published by an EWI critic from Germany:

http://www.konrad-fischer-info.de/2133bau.htm



The green stuff is algae.
The grey stuff (with the white dots) is mould.

In the EWI trade two synonyms are used for these failures, "leopard" pattern for the dotted appearance and "alligator" pattern for the striped appearance.

Both patterns are caused by life forms thriving with moisture. Hence my question concerning driving rain loads in the previous post, see above.

Any comments from our EWIS traders and installers?


About rain exposure/dew formation see page 2 (Abstract in English) on this document:

http://www.hoki.ibp.fhg.de/ibp/publikationen/fachzeitschriften/WTA-Schriftenreihe_Heft_28_S49.pdf


Picture 9 shows an EWIS element after 12 years of exposure at an angle of 30 degrees.......


Sure someone who has decided that the tax payer forks out €4.000 per subsidy case for EWI done by factory trained amateurs in Ireland can comment ?!