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