Can i use an extra leaf of brickwork instead of external insulation?

trevfitz

I am looking at the options of insulating my home. The house is built with 9" cavity blocks so I was thinking of building an external leaf of bricks instead of the external insulation as it would be cheaper (im a brickie so labour cost reduced). any experts out there know if this would be advisable or what other options are available as getting the wall pumped is out of the question as its only guaranteed to insulate up to 75% of a cavity block wall and the external insulation is only guaranteed to last 10 years!
suggestions and ideas would be greatly appreciated.

BryanF

I would be concerned about the movement/foundation support of the proposed external wall, (maybe consider the planning implications..) i appreciate re-bar can be drilled in to the existing and the new poored around, but I would be calling the services of a structural engineer, just to check their preferred method..
if you were going to this, how wide would you make the cavity? the 200mm is now becoming the norm with some going as much as 300mm wide cavity's..
what wall ties will you use - I presume you would pump the cavity afterwards as otherwise you'll have a hard job ensuring the insulation is completely sealed with no gaps to the inners side of the wall when dealing with the ties.
( this may be petty but) is the outside rendered or pebble dashed or painted - if it were me i would be considering what barrier this may be to the house breathing or looping of air, now that your insulating the outside of it..

another method would be to go with an external rigid (but breathable) mineral wool or wood fibre product basically EWI but with a rain-screen cladding that could be clad with a cement fibre board & plaster painted or even timber cladding..

what ever you decide to do consider your window, threshold and eaves details and the overlap of insulation with these elements to reduce thermal bridging..

I think your comments re EWI are more about the 'one week course cowboys', who are not even plasters to begin with! ie the lower end of the market, as the EWI method of insulation has been used successfully on the continent for 40 years. check out STO for one of better ends of the scale

(Bring on Heinbold with some horror stories:D)

whatever you do, if dry-lining is raised/suggested, don't over insulate the internal walls by more than approx 50mm or you run the risk of interstitial condensation. + consider carefully the impact that new insulation/ air-tightening will have on your houses natural stack ventilation..

do note that under the current Building regs home alterations of this type should take account of TGD L 2011 I'd also recommend a look at this

trevfitz

thanks for that, and the links, very helpful. I was just going to put up a leaf approx 20mm from the original wall face, tie it to the wall with wall starter ties and stuff thin rockwool or similar in the gap.... proper cowboy job which probably would have led to future problems. the SEAI link is very useful, appreciate that.

heinbloed

I'm amazed that people think there is a legally enforceable guarantee on EWIS, whenever I ask for written information on this issue there is a big silence.
Please, BrianF, some links to any guarantees by the EWIS installers/manufacturers. Thanks.


Here a little abstract from a discussion forum in the UK where I've linked some official horror experience:

Here a few samples from the EU continent where fascades ignite entire buildings including neighbouring buildings, of course all EWIS done according to the books :

http://www.spiegel.de/wissenschaft/technik/0,1518,800017,00.html

http://www.kohlhammer.de/brandschutz-zeitschrift.de/download/Brandschutzartikel/PDF/0605_Kircher_Fassadenbrand.pdf

http://www.haz.de/Hannover/Aus-den-Stadtteilen/Sued/Hoher-Sachschaden-bei-Fassadenbrand

http://www.fireworld.at/cms/story.php?id=17299

http://www.blaulicht.at/index.php?id=28&tx_ttnews[tt_news]=2849&tx_ttnews[backPid]=4&cHash=f295e3a9ed

a movie from the German TV statio NDR showing the official testing of an EPS EWIS, a total desaster:

http://mediathek.daserste.de/sendungen_a-z/432744_plusminus/8860824_daemmwahn-nicht-immer-macht-energiesparen-sinn?buchstabe=P


A fire storm expanding over the fascade of 5 buildings, a burning dustbin caused it:

http://www.ndr.de/regional/niedersachsen/oldenburg/delmenhorst153.html

Click onto "Delmenhorster spenden fuer Gross-Brandopfer, Bilder 1-14"

here a facade/EPS fire in France/Paris:

http://www.youtube.com/watch?v=MgcJg-kUYgk

Mc Donalds in St.Pauli/Hamburg

http://www.youtube.com/watch?v=dqpYGkdQQV0
http://www.youtube.com/watch?v=dqpYGkdQQV0



What's about increasing the taxes on insulants to cover additional costs to the infrastructure, to society? Has the ozone hole been paid for by those who caused it ?


Fire brigades 'love' insulants, here a few pictures from an Austrian fire officer:

http://www.einsatzdoku.at/module-news-display-sid-773.htm


Do British fire brigades receive special training concerning facade fires? With all the different methods of fixing and different materials used? Are the costs for this training covered by the 'tax-free insulant' industry?
I would say that this isn't the case. But sure some tax specialist like the OP has done his home work .....

From: http://www.aecb.net/forum/index.php/topic,3397.30.html


Here a burned out STO facade:

http://www.kohlhammer.de/brandschutz-zeitschrift.de/download/Brandschutzartikel/PDF/0605_Kircher_Fassadenbrand.pdf

And here a soaked wet EPS STO facade, officially researched by the Fraunhofer building research institute:

http://www.rkw.de/fileadmin/media/Dokumente/Publikationen/Frankfurter_Bautage_2010_Kunzel.pdf

See page 20/22. 10% water (per volume) in the EPS. STO system, fixed accordingly to the manufacturer's instruction by specialised craftsmen. Now rottening.

Carlow52

BryanF (Bring on Heinbold with some horror stories)

I think heinbloed has met the spec here:D

In passing STO is the name of a manufacturer of EWI stuff and not something you catch when.......Gone Fishing:)

heinbloed

The OP want's to ad extra insulation to the external wall.

The house is built with 9" cavity blocks......

Are these hollow blocks ? There are cavity walls but not cavity blocks - as far as I know ....

.....I was thinking of building an external leaf of bricks instead of the external insulation as it would be cheaper (im a brickie so labour cost reduced).

It would be cheaper to put up EPS and plaster it (per calculated thermal insulation gain).

With both methods (EPS/mineral wool or brick cladding) a wufi calculation is demanded. As well as a structural survey and calculation, weigth and wind load as well as water ingress and moisture build-up have to be considered before any aproach can be recommended.

There are nowadays mineralic foam boards available which neither rot nor burn and can be used for external insulation.

.....the external insulation is only guaranteed to last 10 years!

Who guarantees that? Any link? Conditions?

Once the max. calculated (!) windload had been exceeded ALL guarantees are non-existent anymore.
With wind loads like yesterday in Scotland (up to 165 miles/h) not a single EWIS there has any guarantee time left. Happy sellers, the stupid buyers did not understand the small print.
EWIS fixed and comissioned last week and now without any guarantee....one storm exposure and that's it with the guarantee.
Note that all EWIS manufacturers demand a windload calculation being done. Not done means no guarantee on anything. Not even the private home insurance would fork out for something that was not done prefessionally.
And none of the EWIS manufacturers guarantees his systems for the Irish climate. It's all up to the buyer and specifier and installer. Read the contracts.

Carlow52

Are these hollow blocks ? There are cavity walls but not cavity blocks - as far as I know ....

Cavity blocks are widely used in Ireland and in the '60s ' the 9" hollow ' was virtually the only game in town
http://www.dimensionsguide.com/dimensions-of-a-hollow-block/

BryanF

Heinbloed, we value your unbiased view of products and systems.

heinbloed wrote: »

The OP want's to ad extra insulation to the external wall.Are these hollow blocks ? There are cavity walls but not cavity blocks - as far as I know ....

the Irish lingo has got you here is all:) we are presuming the 'brickie' (block layer) knows what he's talking about;)

It would be cheaper to put up EPS and plaster it (per calculated thermal insulation gain).

With both methods (EPS/mineral wool or brick cladding) a wufi calculation is demanded.

I agree but I've yet to meet a client willing to pay for it..

As well as a structural survey and calculation, weigth and wind load as well as water ingress and moisture build-up have to be considered before any aproach can be recommended.

yes on bigger jobs Ive have ask the engineer for these details - on domestic work your reliant on the better system providers to do the calcs

mineralic foam boards

i meant to say mineral borads not mineral wool, can you post a link to the type of products your taking about?

Who guarantees that? Any link? Conditions?

you know as well as i do the only guarantee you get on any of these systems is only what's written/ prescribed the certification (IAB or BBA)

Once the max. calculated (!) windload had been exceeded ALL guarantees are non-existent anymore.
With wind loads like yesterday in Scotland (up to 165 miles/h) not a single EWIS there has any guarantee time left. Happy sellers, the stupid buyers did not understand the small print.

thats interesting have you approached any of these system providers for their opinion/ confirmation of this

Note that all EWIS manufacturers demand a windload calculation being done. Not done means no guarantee on anything. Not even the private home insurance would fork out for something that was not done prefessionally.

i agree this should be done, and often is on commercial, but again - the nature of the self-certifying contractors in Ireland do not do this and the client wont pay for this, so imo were back to the 'need for building control debate' or some kind of enforcement..

And none of the EWIS manufacturers guarantees his systems for the Irish climate. It's all up to the buyer and specifier and installer. Read the contracts.

yes and that's why I wrote

the 'one week course cowboys', who are not even plasters to begin with! ie the lower end of the market

BryanF

just on the fire issues raised - all Irish systems must have fire barriers at each floor level and between each unit/apartment/dwelling..

heinbloed

I have asked for a link to any guarantees concerning EWI and BrianF posted

Quote:
Who guarantees that? Any link? Conditions?
you know as well as i do the only guarantee you get on any of these systems is only what's written/ prescribed the certification (IAB or BBA)

Please put a link here so we can follow these strange guarantee claims. A state organisation can by no way guarantee for the quality or durability of a private business.

This would be against various principles of free trade and enterprise, an illegal subsidy.

So publish the links please.

trevfitz

[QUOTE=
Please put a link here so we can follow these strange guarantee claims.[/QUOTE]

I dont have a link or proof of these claims, just what I was told by the 3 people on my street who have had it done, they said they got a 10 year guarantee and a repair manual!

also sorry for the hollow block/cavity block confusion, they are the same thing, but I and most people Ive worked with call them cavity blocks, but there are some who call them hollow blocks.

heinbloed

Thanks, trevfitz!
Would you mind to tell us where we can read these guarantees?
Maybe you could ask one of your neighbours to give you a copy and you could publish it (anonymized!) here?
None of those in the trade seem to have seen something like it before. I installed EWI for a few years, some thousand m2 but never came across a written guarantee. Except the specifier's ( civil engineer's) indemnity insurance.

Thanks.


The strange thing about this obscure guarantee is also

I dont have a link or proof of these claims, just what I was told by the 3 people on my street who have had it done, they said they got a 10 year guarantee and a repair manual!

Why would a company making a 10 year guarantee time not turn up and do the repairs themself? If a manufacturer's guarantee on a car would mean that all repairs must be done within the guarantee time by the owner we would have the consumer's ombudsman interfering.

Really, such a phrase as

they got a 10 year guarantee and a repair manual!

should make us wonder why people shop with such a company.

Carlow52

trevfitz wrote: »

thanks for that, and the links, very helpful. I was just going to put up a leaf approx 20mm from the original wall face, tie it to the wall with wall starter ties and stuff thin rockwool or similar in the gap.... proper cowboy job which probably would have led to future problems. the SEAI link is very useful, appreciate that.

20 mm is not worth the effort