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    • CommentAuthorgravelld
    • CommentTime5 days ago edited
     
    Regulars will have noticed my regular naive posts about EWI, installing windows etc etc.

    After taking a step back I have decided not to pursue the EWI segment. Instead, I'm reviewing a render only solution, while still installing high quality windows, full filling the cavity an treating the eaves properly.

    The first reason is cost. Not just treatment of the actual wall (although it appears about double the cost to insulate and render), but the the downstream works:

    - Extending gables
    - Digging foundations
    - Moving drains
    - Treating lean-to roofs at the same time

    The second reason is complexity. First world problems and all that, but I have run out of mental energy both to try to understand, design and plan this, while also running a business and bringing up a young family. Obviously, I could hire someone to do that, but please see the first reason.

    Quite honestly, I feel revitalised since deciding to dith EWI.

    My intention is to pursue EWI later, maybe in a decade or so. In some ways I think the end result might be better - it allows more budget to purchase better windows, and we could do the EWI at the same time as the roof later, allowing us unlimited space at the eaves.

    So now I need to consider how going render-only will affect things. I am considering the full gamut:

    - Ignoring the render and hoping no-one gets hit by falling patches
    - Just patching what we have
    - Removing and re-rendering with S+C
    - Removing and re-rendering with a silicone system
    - Removing and re-rendering with an insulating render, e.g. Bauwer, Diathonite

    I know BC might raise an eyebrow if we remove and re-render as we are treating more than 50% of the wall. Hopefully the fact that we are also full filling the cavity AND using a high performance window product will convince them of good faith alongside our intention to fit EWI later.

    I am considering the window detail separately... see http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15728

    Any thoughts on the re-rendering options?
  1.  
    If you are saving money, mental energy and intend to add EWI at a later date why would you do anything other than nothing or "just patching what we have"?

    I obviously don't know the specifics of your project / situation, but given the rest of the post it seems the logical thing to do in the circumstances.
    • CommentAuthorgravelld
    • CommentTime5 days ago edited
     
    This is exactly the type of response I hoped for when I posted - to further challenge my preconceptions. My thoughts:

    I'm not sure how much patching up is required. I would estimate 10% of the render is blown, small cracks cover 80% of the render across all elevations and 15% of the corner beads have rusted through and require replacing. There are a few places where there are holes in the render at the corner of windows for water to get behind. Also the base track is shot in a number of places.

    This render layer will likely form the AT layer in the future, so having cracks in it is a no-no. I don't think it's any good anyway because of water ingress that may/may not occur.

    An EWI person also suggested looking at the substrate behind the cracks, because if that's cracked we should really do something about it (straps or whatever an SE says).

    I asked a local lime plasterer to look, he came to the conclusion we might as well take it all off... but maybe he would say that ;-)
  2.  
    Wot Richard said +1
    Also
    Posted By: gravelldwe are also full filling the cavity

    and
    Posted By: gravelldsmall cracks cover 80% of the render across all elevations and 15% of the corner beads have rusted through and require replacing..........This render layer will likely form the AT layer in the future

    Would you normally have the air tightness layer outside the cavity?
    The general advice is if the render is not blown then leave it on and EWI over it. Obviously it depends upon the condition and stability of the render that is not blown and sometimes it can be difficult to differentiate between 'good advice' and 'job creation'
    • CommentAuthorgravelld
    • CommentTime5 days ago edited
     
    Posted By: Peter_in_HungaryWould you normally have the air tightness layer outside the cavity?
    Yes, on retrofit and when you don't want to create massive internal disruption.

    PU foam will offer some AT benefits but it won't be continuous because there are some sections of full fill EPS for which I cannot guarantee AT, so therefore it's the render layer.

    Posted By: Peter_in_HungaryThe general advice is if the render is not blown then leave it on and EWI over it. Obviously it depends upon the condition and stability of the render that is not blown and sometimes it can be difficult to differentiate between 'good advice' and 'job creation'
    Agree. As above, I'm not EWI'ing.
  3.  
    Posted By: gravelld
    Posted By: Peter_in_HungaryWould you normally have the air tightness layer outside the cavity?
    Yes, on retrofit and when you don't want to create massive internal disruption.

    But this means that the cavity has to be air tight - which could be a big ask.

    Posted By: gravelldI'm not EWI'ing.
    - Yet
    • CommentAuthorgravelld
    • CommentTime4 days ago edited
     
    Posted By: Peter_in_Hungary
    Posted By: gravelld
    Posted By: Peter_in_HungaryWould you normally have the air tightness layer outside the cavity?
    Yes, on retrofit and when you don't want to create massive internal disruption.

    But this means that the cavity has to be air tight - which could be a big ask.

    Well... the render layer outside the cavity has to be air tight, yes, and then connections to the roof etc.

    Posted By: Peter_in_Hungary
    Posted By: gravelldI'm not EWI'ing.
    - Yet

    Correct, so I guess another option is just let the render fall out over the decade or so it takes to save up for EWI and look worse and worse with time.... note there is also some holes in the render at windows, which water could get behind. I don't think combining a full fill cavity with a wet external leaf is a good idea...
    • CommentAuthorgyrogear
    • CommentTime4 days ago edited
     
    Posted By: Peter_in_HungaryWot Richard said +1


    +1.

    OR why not cover it over with temporary protection idem a damaged roof post storm/fire/act of dog/waiting on insurance assessors - viz. tarps, ropes, battens: it could remain in this "temporary state" for as long as you could stand to see it...

    I would not re render it, personally, since you are planning on EWI when U get fettled _ just an illogical waste of resources -- in French this is known as "killing the green advantage"

    gg
    •  
      CommentAuthordjh
    • CommentTime4 days ago
     
    Paint it with some strong paint, so the render is held together by the paint, and the cracks are filled by it.
    • CommentAuthorgravelld
    • CommentTime4 days ago
     
    Interesting responses, wasn't expecting this.

    @djh do you have some names of paints in mind, not really sure what constitutes a "strong" paint?
  4.  
    Gyrogear, which particular act of a dog would require us to sheet up a whole building?! I await your reply with bated breath!!
    • CommentAuthorgyrogear
    • CommentTime4 days ago
     
    LOL !

    Apologies for the typo, I meant, "Act of Brian" of course !

    gg
  5.  
    10 years is a long time to wait before you fit EWI. 10 years of a colder home, higher energy bills and a decade less for the ROI. I'd suggest that if you're 'kicking the can' down the road for a decade, then the EWI just isn't going to happen and you should perhaps accept that. and move forward?

    Instead, I'd look at alternatives. Perhaps put EWI on a single wall (i.e. a north wall) and render the rest. If that's not possible then see if there are some insulated renders available. The combination of an airtight and slightly insulated render that sheds moisture is going to be more thermally beneficial than a patchwork of blown, leaky render.
    • CommentAuthorgravelld
    • CommentTime4 days ago edited
     
    It might not happen @Pile-o-Stone which would be a great shame. Thanks for your thoughts.

    Short term I have to weigh up the financial cost to the family and what else we can do with the money. We *can* heat the house enough at the cost of a lot of dinosaur bones (and some money, but oil is cheap really).

    Essentially, retrofit is a lifestyle choice in the UK. I'm convinced it's the _right_ thing to do, but there are a lot of _right_ things to do - it comes down to choice. Some of us have more choices than others. I'm lucky to have more choice than others, but I don't quite have the wealth for this.

    There's no support from Government for this other than lower VAT on the EWI (if you call a tax that new builders are otherwise exempt from "support").

    So my conclusion is to hope somehow EWI becomes more affordable in the medium term or I have a "liquidity event" of some sort.

    Back to now, that's why I mention Bauwer/Diathonite. The lambda is at least at the same order of magnitude as other insulants so it could be considered an "insulant" I think, and could contribute to the fabric both now and long term.

    My original plan was for EWI only on certain faces. But it turned out to be more complex - having to return the EWI on the untreated wall, which would be cut back later, but that would just look crap and offers weakness at the junction between old wall and insulant. Plus if it's a gable you still have extension problems and if it's not I'm limited by the eaves depth (or I have to extend the eaves).

    My general reading of PHI recommendations for retrofit is, if it's incremental, do each piece to a high standard and reduce compromises. I see things like limiting the depth at the eaves a compromise.
    •  
      CommentAuthordjh
    • CommentTime4 days ago
     
    Sorry, I missed out a :tongue: icon :sad:

    But there are loads of flexible paints, and crack fillers.
    • CommentAuthorKenny_M
    • CommentTime4 days ago
     
    gravelld, I feel your pain. Demanding job, pre school child and a PhD. Financially I can afford to do this stuff, but I probably can't afford to pay someone to look after it all for me, so as you say its the mental energy that needs to go into it all. Having a period property in a conservation area just makes it more complicated.

    As far as ROI which has been mentioned before, or what it would cost not to do it, I don't believe there is an ROI for almost any of the improvements you can make on a retrofit, beyond maybe loft insulation and draughtproofing. I did an ROI on replacing my 30 year old boiler and it was longer than the projected life of the new boiler. I did the calc for EWI and windows too and there was no way it would have given me a return. I think it has to be about believing in the principle of reducing energy usage.

    WRT your render, as has been said already, make it safe and leave it until you are ready to make a decision on the EWI. Mine has been boss for years by the looks of things, but it seems to hang together. I ended up getting it taken off recently on the one side where if it fell it could really hurt someone, and have left the rest until I am sure about what I am going to do next, but the section that was just taken off I had left for over a year and just barred it off so no-one walked down that side.
    • CommentAuthorgravelld
    • CommentTime4 days ago edited
     
    Posted By: djhSorry, I missed out a http:///newforum/extensions/Vanillacons/smilies/standard/tongue.gif" alt=":tongue:" title=":tongue:" > icon http:///newforum/extensions/Vanillacons/smilies/standard/sad.gif" alt=":sad:" title=":sad:" >
    I did wonder!
    • CommentAuthorgravelld
    • CommentTime4 days ago
     
    Thanks Kenny, PhD as well, you must be some sort of super human.

    Just to be clear, I understand ROI is poor, that's not why I'm doing it. I'm doing the retrofit overall for comfort, health, lower maintenance and because it is, in theory, the right thing to do for all sorts of other reasons - environmental, successor occupants etc.

    The problem is not any sort of ROI but the cost for those improvements.

    If we patched the popped bits, filled in the holes and the cracks, anybody have any thoughts on how long it would last? Sand and cement remember?

    I think I should get some quotes.

    Also, recommended fillers, if such a thing as a flexible filler exists.
    • CommentAuthorKenny_M
    • CommentTime3 days ago
     
    Posted By: gravelldPhD as well, you must be some sort of super human.
    - no, more like someone who has taken on too much and is ending up getting nothing finished!

    I squeezed some sand and cement into some of the cracks in mine, how long it will last is anyone's guess. In my case the base coat is absolutely solid to the wall, and its the harled outer coat is detached from the base coat. I considered at one point removing the out cot and leave the flat base coat, but I don't know if yours is coming right off down to the brick/stone.
    • CommentAuthorgravelld
    • CommentTime3 days ago
     
    Something to consider... but of course it might vary on different parts of the wall.
  6.  
    Posted By: gravelldIt might not happen @Pile-o-Stone which would be a great shame. Thanks for your thoughts.


    I know how you're feeling, and like Kenny_M, I feel your pain. I have a long list of things I'd like to carry out on our old, cold house but lack of funds are also proving to be restrictive. Our original plan was to internally insulate our house a room at a time, as we renovated/redecorated. We have one room fully insulated and should be looking at moving onto the next one (our living room). However, the cost of insulating, moving radiators & power sockets, re-plastering, re-flooring and the massive disruption and emotional drain is making us rethink the whole thing.

    We have made a big improvement to the heat retention of the livingroom by replacing an old multi-fuel stove and replacing it with a room sealed gas stove. When it was off, the old stove must have been acting like a big heat sink and sucking warm air out of the living room. We certainly have felt a huge improvement since we replaced it. We are now looking at moving the doorway into the living room. Currently there is a double door that opens into the heart of the room, causing a draft right where we are sitting when the dog or cat push the door open (and they can't just open it a little - they seem to have to open it as wide as it goes!). Instead we are moving the door to the end of the room, far away from where we are sitting. Hopefully this will be another relatively minor (in expense at least) change that will have a big impact on the thermal dynamics in the living room.

    What I'm trying to say is that you should try and get some cheap/quick wins that might reduce your energy bills by 30% for little financial outlay, and not stress too much about the big jobs that might reduce your energy bills by 80% but will never repay in your lifetime.

    I've joined a renewable energy company for my gas & Electricity. I take cold comfort in the idea that at least the energy I'm wasting is green :cry:.
    • CommentAuthorgravelld
    • CommentTime3 days ago
     
    Indeed - thanks @Pile-o-Stone.
    • CommentAuthorMarkyP
    • CommentTime2 days ago edited
     
    the payback of insulation improvement is obviously an important factor. I've EWI'd my large bungalow and recent extension, it was hard work both mentally and physically. But my aim was both reduced heating bills and a much improved living environment. This winter was a revelation, the house was still reasonably warm in the mornings after very cold nights with no heating having been run for at least 10 hours. And no more mold growing on the inside walls in cold corners. Interior temperature is much stabilised, fluctuating mostly in a 3 or 4 degree range rather than big 10 degree swings in some rooms when the heating was off. And the thermal envelope is not yet complete, I still have to do the below DPC line plinth insulation to foundations. And while we have loft level insulation, it's thin and patchy, the upper floor has been converted for occupation but is not yet insulated, once done I think it's going to bring further improvements to the living conditions and I expect interior temp to stabilise further. MVHR also planned.

    if you can EWI, now or later, I highly recommend it. It's more than just reduced heating bills, in my case it's made our home a much nicer place to live.
    • CommentAuthorgravelld
    • CommentTime2 days ago
     
    Yes, the latter is what I'm trying to achieve.
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