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External Insulation question

  • 15-04-2022 10:07pm
    Registered Users Posts: 2,041 ✭✭✭


    My relative is having 100mm external insulation installed under seai. Replacement footpaths, new door, ramp, steps and rail to be installed under a different scheme. Which order would they need to be done in, or does it matter. I was thinking new door may need to go in first, then ewi, then replacement footpaths (mainly due to gully's, etc moving out 100mm) , ramps, steps, rails?

    Note. It was confirmed that the ewi contractor will install to the level of the existing footpath only, which I believe is the standard practice in almost all cases.




  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    When external insulation is fitted, it is necessary to move the windows and external doors out to be fixed in to the external insulation - so that the original block wall will not be a cold-bridge.

    I’m very sure that some of the SEAI ‘Experts’ will probably explain why there is no need to do this.


    Remember when these SEAI “Experts” advise you that the be best thing for YOU for your home is to wrap it in External Insulation.

    If your home has a Cavity constructed external wall with gables, then the cavity of the gable walls are normally not closed, so the NEW external insulation will be redundant, even if you do obtain an ‘A’ BER Cert. 

    When Heat gets a choice of escaping by either Conduction OR Convection, Convection always wins. (up up and away) 🔥🔥🔥

  • Registered Users Posts: 2,041 ✭✭✭gooner99

    Thanks for the reply. Unfortunately under the SEAI scheme it's a take it or leave it approach. They don't offer window replacement or moving windows out.

  • Registered Users Posts: 2,041 ✭✭✭gooner99

    The cavity (60mm) was pumped with mineral wool a number of years back. This was causing problems especially along the west coast where is was getting wet/damp. Up until recently the SEAI and local authorities were extracting this insulation and re-pumping with bonded bead. But seems that recently they are leaving it in place and externally insulating. Wonder which option is best?

  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    gooner99 hi

    If the “Insulation Experts” do not move the windows and external doors out to the new external insulation, the concrete block walls between the frames and Insulation will form a cold bridge. This cold bridge will have a high U Value and cause heat loss at these junctions.

    This cold bridge could also cause Surface Condensation on the surface of the internal walls around the frames.

    See Sketch of a Cavity Block Wall:-

    Does anyone know - what Insulation Experts trained these “new” SEAI “Insulation Experts”

    Heat will flow out - and the cold will flow in at the concrete cills. Concrete Cills:- Cold Bridge and Condensation.

  • Registered Users Posts: 6,744 ✭✭✭SuperBowserWorld

    Wow, I'll just sit on my arse and wait for the taxpayer to pay to insulate my house twice, and the government and local authorities, all 2045 local authorities, and their consultants to figure out how to insulate a house properly.

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  • Registered Users Posts: 3,666 ✭✭✭chooseusername

    The cavity in the op's case was pumped, so it's obviously not a 'cavity block' wall.

  • Registered Users Posts: 2,041 ✭✭✭gooner99

    Thanks. The existing wall isn't made up of cavity blocks. It's double leaf block with a cavity.

  • Registered Users Posts: 2,041 ✭✭✭gooner99

    To clear things up. House is not under a local authority, it's a private dwelling availing of much needed grant aid at this time. The cavity was pumped a long time ago by a private company. It turns out they used material that was approved but has since been condemned for use in cavities on exposed locations. Luckily in this case, damp has not yet become an issue.

    I only mentioned local authorities as they apparently had a higher instance of this material being used. I'm not aware of the numbers, only what the solutions employed were.

  • Registered Users Posts: 6,744 ✭✭✭SuperBowserWorld

    Ok, just annoyed that I'm here worrying about house insulation and costs and some people get this done for free without even having to think about it and done twice cause the authorities can't follow specs and technologies that have been tested in other countries for years.

  • Registered Users Posts: 2,660 ✭✭✭scwazrh

    Ive yet to see any contractors remove the windows and doors to allow for fitting of external insulation.Yes it would be a better method but retrofitting is about being pragmatic and aiming for the best results reasonably possible.One of the benefits of external insulation is that you do not affect internal finishes .Removing windows and doors would conflict with this.

    As the wall is cavity wall ,you can ask the fitters to remove the external reveals and fit a thinner insulation to the reveals.This will also allow for masonry to window frame sealing and help to achieve the best possible result.

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  • Registered Users Posts: 2,041 ✭✭✭gooner99

    No problem. Wasn't sure if you were having a go at the person getting the grant aid which is badly needed or the system. Thanks for clearing it up. Yes, it's reflects badly on those approving these systems.

  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    That was a disaster then, and you say that the SEAI and Local Authorities are blaming the West Coast. They forgot to include “Once Upon a Time in a land far far away (in the West)” 😂😂😂😂.

    I witnessed many of these disasters inland in the south.

    This has absolutely nothing to do with the location of these debacles. I presume from the statement above that the SEAI and the Local Authorities were the instigators of these terrible debacles using Cheap Cowboy “Insulation Experts” supervisor by their own “Experts” - Delboy and Trotters Trading Company, Peckham, Paris and Dublin - no money back, no guarantee - You couldn’t make this up!.

    Building Science:-

    The purpose of a cavity, in a cavity constructed wall - is to prevent moisture getting in to the inner concrete block leaf above the DPC, and they function perfectly.

    When a Cavity is filled in these walls, the insulation will fill the wet/damp cavity below the DPC (Damp Proof Course) which is usually 225 mm below the DPC. Some of the cheap wool (unapproved) insulation are porous (similar to the wick in an oil lamp). Damp/ moisture /water is very intelligent and must get in to this insulation and must travel up above the DPC and will then soak in to the very porous internal concrete block inner leaf, and will evaporate on the surface of the internal plaster in the form of efflorescent salts. Some of this dampness will also evaporate through the external leaf of the wall. This process will never stop until the incorrect cavity fill insulation is removed. Fitting External Wall Insulation will not prevent the dampness from below the DPC from causing dampness / efflorescent salts on the inside of the wall.

    Every time these salts are cleaned off and the wall repainted, the dampness will always reoccur until the incorrect insulation is completely removed from the cavity.

    I got a quote for a client about a year ago to remove the fill from a cavity in a bungalow and it was €5,000.

    Fitting EWI (External Wall Insulation) on these walls will exacerbate the internal dampness because the moisture is now prevented from escaping externally. So now ALL the rising dampness in the cavity insulation can now only escape through the internal wall of the cavity.

    The untold damage this causes and the mental stress of home owners and their families and their relationship is unimaginable.

    All of this is not Rocket Science - it’s Building Science.

    Minister Ryan and Minister Darragh and all their Departments may all be “Experts” in this, especially when there are over 2 million homes in England with these terrible problems [I wonder are all of these homes on the West Coast of the UK]. Of course all the “Expert Insulation” Companies are gone with their 50 year guarantee.

    Of course many of our “Expert Insulation Plonkers” have been “Reskilled” and “Upskilled” by FAS Experts. (They haven’t gone away you know).

    Another disaster like Mica and Pyrite disasters on the way, except this one is scripted by our Government.

  • Moderators, Society & Culture Moderators Posts: 38,931 Mod ✭✭✭✭Gumbo

    While I normally agree that the EWI and windows should be in one plane, the retrofit grant won’t go to this extreme.

    Especially when the Government release Acceptable Construction Details that show the windows fixed to the inner block.

  • Registered Users Posts: 6,744 ✭✭✭SuperBowserWorld

    How can people all over Europe, Sweden, Poland, Finland, ... , ... Germany, Ukraine ...insulate their properties for decades successfully

    And Ireland and the UK , end up reinventing the wheel and doing it wrong ???????????????

  • Registered Users Posts: 757 ✭✭✭C. Eastwood


    You asked - which option is best.

    The best Option is for you to have Insurance.

    Retain a Construction Professional with Professional Indemnity Insurance to advise and supervise and Certify the completed insulation retrofit by the SEAI “Insulation Experts”. Get everything in writing. If there are any problems with the retrofit - then you can sue the PI Insurance for the costs to rectify the problems.

    (Read the article in my last post above about the families in England who must wait and wait for the Politicians to do something).

    I have been accused on this forum of touting for work and I want to make it very clear to everyone reading my professional advice here,- that I do not want any work from anyone under and circumstances, and I never reply to any emails from anyone in

  • Registered Users Posts: 757 ✭✭✭C. Eastwood


    In Cavity constructed walls - the windows and external doors should be moved out in to the EWI.

  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    The problem in the building industry is that many people assume the obvious.

    There are many houses in Ireland where Cavity Block Walls ( Walls constructed with 215 mm Hollow Concrete Blocks) were pumped with the worst type of foam insulation, which caused terrible rainwater ingress. I have dealt with some of these properties. The huge problem here is that it is not possible to extract the insulation. They were Brilliant Salespersons.

  • Registered Users Posts: 6,744 ✭✭✭SuperBowserWorld

    Thanks for the sound advice.

    It's a minefield out there.

    The building regs on this need to be enforced and people need proper training and skills to do this retrofitting correctly.

  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    All this sounds brilliant in theory.

    In practice this what will happen as it is Building Science:-

    If your home has a Cavity constructed external wall with gables, and the cavity is not filled, the cavity of the gable walls are normally not closed, so the NEW external insulation will be redundant, even if you do obtain an ‘A1’ BER Cert. 

    When Heat gets a choice of escaping by either Conduction OR Convection, Convection always wins. (up up and away) 🔥🔥🔥.

    In plain English, when the temperature is lower outside- the warm air in the house must move to the lower temperature outside, therefore it must travel through the inner leaf of the external wall by Conduction to get to the lower temperature. When the warm air is in the Cavity it has a choice- it can either go out through the external block leaf by Conduction OR rise up in the Warm air inside in cavity - by Convection to escape in to the cold air through the top of the ventilated cavity. CONVECTION always wins - it’s Building Science.

  • Registered Users Posts: 2,041 ✭✭✭gooner99

    Yes. My understanding is that they will add a thinner strip to the window/door reveals. This was the reason I was thinking the new door would need to be installed first. All windows have a standard depth reveal. But this door is a couple of foot inset from the external elevation.

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  • Registered Users Posts: 757 ✭✭✭C. Eastwood


    I am in total agreement with the Grant and insulating homes. This is very important for the families to have warm homes that are very cheap to heat.

    I have had to deal with terrible dampness problems in houses that caused terrible problems to families for very long periods of time, and are very expensive to rectify

    What I detest is the damage caused by government approved schemes by Cowboys that cause terrible damage to persons Homes and the damage to the Families and that there are no Guarantees or Insurances to give some immediate help to the families. They have to wait year after year and so on.

    The government should insist that these “Insulation Experts” must have Insurance against shoddy building works and to provide insurance for the 40 year Guarantee.

    The Government should insist that all of retrofitting by these Expert Companies is Supervised and Certified by a Construction Professional with PI Insurance.

    We are talking about serious money here not peanuts. Many families will have to take out loans. Cost Analysis will show that Payback time for the investment will take years to replace the money that would have otherwise been spent on fuel.

    All Construction Professionals who hold Professional Membership of Professional Bodies must have Professional Indemnity Insurance. These Expert Insulators should also be covered by P I Insurance.

  • Registered Users Posts: 2,041 ✭✭✭gooner99

    Thanks c.eastwood. This thread is both interesting and frightening. My understanding is that the wool in this particular cavity was approved and is not damp. It was installed about twenty years ago and so far no damp in the house. Seems like there is no ideal solution for older houses with narrow cavities. If you extract and refill with bonded bead then the uvalue is still poor and the external method utilised has its own problems.

    Can I ask you a couple of other questions.....

    If nothing is done at all to the house, then surely the reveals are a cold bridge anyway as well as other points. Would adding external insulation not reduce cold bridging in general?

    My own house is off a similar era with 60mm cavity and I was thinking of going with external as part of a deeper retrofit. My walls are pumped with loose white bead. Do you think I would be ok if I get the loose stuff removed, repumped with bonded bead, move or replace windows/doors out to the ewi. Or should I explore other solutions like internal, or....?

  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    Ireland and England have a very damp climate and very high Relative Humidity.

    Many if the workers are Not Qualified Craftspersons.

    Think of FAS - ReSkilling and UpSkilling.

    No knowledge of Building Science. Cannot be learned in a FAS crash course

    Persons teaching Building Sciences need to have an expert knowledge of the Science.

    In Germany no construction works are allowed to be carried out unless there is a Meister (Qualified Master Craftsperson) of that Trade - present on site.

    We don’t even have Craftspersons doing the Retrofit.

    You couldn’t make this up.

  • Registered Users Posts: 6,744 ✭✭✭SuperBowserWorld

    It's a tragedy, especially so soon after the last boom and bust. And it's not for lack of money. The government has had years to prepare for this, and they are acting like rabbits in the headlights mode always. And we are going to spend billions creating more problems.

  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    I wouldn’t worry about the €billions - sure the Government will pay the Bills. Won’t cost us a cent. All sorted.

    The savage long term damage that will be caused to Families can never be undone.

    Ministers Ryan and Darragh we’ll be long gone in their holiday homes abroad with their huge pensions. (Irish Accountability)

    R.A.A. Responsibly Authority and Accountability.

    There will never be any person held Accountable, for the debacle that is about to unfold and be unleashed on Home owners over the next few years.

    There is a huge shortage of Qualified Craftsperson in Ireland because Minister Quinn removed / closed down many Apprenticeship Courses in the Institutes of Technology in 2001-02. (Irish Accountability)

    My solution:- I wouldn’t allow any one of these SEAI approved FAS trained Expert Insulation Plonkers near my Home. It is safer to keep paying for Oil and Solid Fuel.

    I swear that I do not burn turf.

    I’m in favour of insulating all buildings. The Grants are very good value. The government’s knee jerk reaction is the problem.

    It’s a pity, that for this Retrofit Scheme that the government did not include existing well established Excellent Irish Home Builders together with Insured Constructional Professionals with the necessary - Education, Training and Experience who are State registered Design Certifiers, and State registered Assigned Certifiers.

    Don’t worry - these people will be there to be retained to fix the problems after the Horse has Bolted.

  • Registered Users Posts: 6,744 ✭✭✭SuperBowserWorld

    "There is a huge shortage of Qualified Craftsperson in Ireland because Minister Quinn removed / closed down many Apprenticeship Courses in the Institutes of Technology in 2001-02. (Irish Accountability)"

    Why did this happen during a construction boom ?


    And nothing to replace it ???

  • Registered Users Posts: 757 ✭✭✭C. Eastwood

    You state that the 60 mm cavity of your external walls are filled with insulation.

    There are 2 types of dampness that can be caused by the cavity fill-

    1. Ingress of rainwater across the cavity
    2. Rising damp in the porous insulation from below the DPC

    Thanks ____________

    Dampness caused by Ingresses of rainwater - only through the external plaster and outer concrete block leaf. Fitting EWI on the outside of the external plaster, provided it’s done correctly AND in accordance with the Manufactures Instructions, then it should prevent any further ingress of Rainwater. No need to extract the cavity fill. Actually the cavity fill will prevent warm air rising in the cavity and the heat must be lost through the wall by Conduction.

    The U value with the EWI would be approx 0.10 Watts/m2/degreeC/hr. The U Value of your existing 60 mm cavity fill will be approx. 0.6 watts/ m2/degreeC/hr. This is a great improvement.

    Rising Dampness:-

    If there is dampness from below the DPC rising up through the porous cavity fill, and up above the DPC and presenting in the form of efflorescences salts above the Skirting Boards. This must be extracted and this necessitates cutting small holes (225 x225) in the wall for the extraction.

    Fitting External Wall Insulation will not under any circumstances stop this rising dampness, and will require holes cut in the new EWI to extract the cavity fill at a later date - no matter what the Expert Insulation Installer tells you. And no one will live happily ever after.

  • Registered Users Posts: 757 ✭✭✭C. Eastwood


    mean to ask you on my last reply- do you understand my reply. Does it answer your question.

  • Registered Users Posts: 2,041 ✭✭✭gooner99

    Thanks all for the replies and information. Very valuable education.

    On my original query.

    House is small rectangular bungalow with standard window reveals and a deeper front door reveal. Works proposed....

    1. External wall insulation.

    2. New low threshold front door, replacement footpaths all round, replace/redo waste gullys, Steps/ramp and rails.

    The best order of works I was thinking....

    1. New front door. (To allow for ewi to be installed on reveals).

    2. EWI.

    3. Replacement footpaths all round, replace/redo waste gullys, steps/ramp and rails. (To allow for ewi to be installed without steps/ramps being in the way, thus giving a greater ewi coverage. Rails not having to be refitted/ adjusted).

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  • Registered Users Posts: 757 ✭✭✭C. Eastwood


    Thank you for your kind comments.

    Your list is copied below

    1. External wall insulation.


    2. New low threshold front door, replacement footpaths all round, replace/redo waste gullys, Steps/ramp and rails.



    The best order of works I was thinking....

    1. New front door. (To allow for ewi to be installed on reveals).


    2. EWI.




    3. Replacement footpaths all round, replace/redo waste gullys, steps/ramp and rails. (To allow for ewi to be installed without steps/ramps being in the way, thus giving a greater ewi coverage. Rails not having to be refitted/ adjusted).