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Housing - Renovation: Concrete floors and solid wall properties

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1 to 19 of 19

  1.  
    • CommentAuthorMatBlack
    • CommentTimeJan 22nd 2020
     
    Hi, I have a question if I may, about the choice between a 'normal' solid concrete floor, and a limecrete floor.

    My walls are solid brick, soon to be lime pointing again. Lime plaster on woodfibre insulation in parts, and possibly eps ewi on some external walls.

    I would like wet UFH, and was set on glass foam (150mm hardcore in already) then ufh set in a 100mm limecrete slab. - throughout the entire lower floor.

    Now I'm pulling the trigger on ordering, money is talking and I can see the huge difference between this system and an eps/concrete slab.

    So my question is, all things considered with measures to let the walls breathe as much as possible, would a eps insulated concrete slab with ufh ever really give moisture problems up the base of the solid brick walls??

    Many thanks for any experiences in this situation.
    • CommentAuthorjfb
    • CommentTimeJan 22nd 2020
     
    I went for EPS/concrete floor with woodfibre IWI/lime/limewash in the end. Mostly for cost reasons and a general assessment that it wasn't too damp. Also put french drains round edges where I could. More choice for floor finish a factor as well. I also had a large area to do and used a pump for the concrete pour - would have been a lot more work doing the limecrete floor.
    Has worked very well - a couple of areas with a little discolouration/salts near the bottom of internal wall but not bad.
    • CommentAuthorgyrogear
    • CommentTimeJan 22nd 2020
     
    Posted By: MatBlackMy walls are solid brick,


    how old are they ?

    gg
  4.  
    Why not go for a hybrid floor? Thick PIR/PUR slab insulation set into concrete in the centre of the floor and limecrete around the edges. Any moisture caught under the concrete slab will migrate into the limecrete slab (rather than the walls) and will be released into the room.


    This chap has a blog on his hybrid floor installation that might provide pointers:
    https://irishfarmhouserestoration.blogspot.com/

    The pic below shows an example of the build up of a hybrid from this site:

    https://www.buildingconservation.com/articles/solid-ground-floors/solid-ground-floors.htm

    (though it doesn't have too much info on the hybrid approach)
      pic_3.gif
    • CommentAuthorMatBlack
    • CommentTimeJan 22nd 2020
     
    Posted By: jfbI went for EPS/concrete floor with woodfibre IWI/lime/limewash in the end. Mostly for cost reasons and a general assessment that it wasn't too damp. Also put french drains round edges where I could. More choice for floor finish a factor as well. I also had a large area to do and used a pump for the concrete pour - would have been a lot more work doing the limecrete floor.
    Has worked very well - a couple of areas with a little discolouration/salts near the bottom of internal wall but not bad.


    Thanks for this, glad its working out ok, floor finish choice.is another good factor!
    • CommentAuthorMatBlack
    • CommentTimeJan 22nd 2020
     
    Posted By: gyrogear
    Posted By: MatBlackMy walls are solid brick,


    how old are they ?

    gg


    The house was built in 1905, fairly soft brick
    • CommentAuthorMatBlack
    • CommentTimeJan 22nd 2020
     
    Posted By: Pile-o-StoneWhy not go for a hybrid floor? Thick PIR/PUR slab insulation set into concrete in the centre of the floor and limecrete around the edges. Any moisture caught under the concrete slab will migrate into the limecrete slab (rather than the walls) and will be released into the room.


    This chap has a blog on his hybrid floor installation that might provide pointers:
    https://irishfarmhouserestoration.blogspot.com/

    The pic below shows an example of the build up of a hybrid from this site:

    https://www.buildingconservation.com/articles/solid-ground-floors/solid-ground-floors.htm

    (though it doesn't have too much info on the hybrid approach)
      http:///newforum/extensions/InlineImages/image.php?AttachmentID=7501" alt="pic_3.gif" >


    Thanks, yeah saw those links! Hybrid floors dont seem like a bad idea, wonder if eps would be ok under all of it!
    • CommentAuthortony
    • CommentTimeJan 23rd 2020
     
    I have a BIG problem with your moisture arrows, in a building that is warmer than it’s surroundings the arrows point in the opposite direction

    The partial vapour pressure of moisture in the air inside the rooms is higher than the pvp outside or below.

    Liquid water will move our wards too all the time when it evapourates
    • CommentAuthortony
    • CommentTimeJan 23rd 2020
     
    I don’t like the joins in the floor, they will introduce cracks, possibly even mini steps, what will the floor finish be
    • CommentAuthorMatBlack
    • CommentTimeJan 23rd 2020
     
    Hi tony, ideally I'd like wood flooring through downstairs, may have to be engineered with the ufh. Concrete would perhaps be a better choice in that respect.

    I'm just apprehensive about any damp coming up around the wall edges. Hopefully the other measures would compensate?
    • CommentAuthortony
    • CommentTimeJan 23rd 2020
     
    If I was doing wood I would want a vapour barrier on the warm side of the insulation and for me that means on top of the wood! But immediately under would be OK, trapped behind the skirtings

    This will also act as a dam and air tightness barrier

    Wood could go on battens or be a floating floor on insulation.
    • CommentAuthorMatBlack
    • CommentTimeJan 24th 2020 edited
     
    Oh ok, so could be hardcore (laid), dpm, 300mm eps, 100ish concrete slab, ufh pipes in concrete screed. Then a vapour barrier immediately under the wood.

    If ufh heating kept on low, hopefully the concrete should never push moisture up round the edges
    • CommentAuthortony
    • CommentTimeJan 24th 2020
     
    That should work.
    • CommentAuthorMatBlack
    • CommentTimeJan 24th 2020
     
    Cracking 👍. Thank you all for the advice
    • CommentAuthorGreenPaddy
    • CommentTimeJan 25th 2020
     
    vapour barrier under wood floor, consider a liquid DPM - paint it on, then you can glue the timber floor to the concrete.
    • CommentAuthorMatBlack
    • CommentTimeJan 26th 2020
     
    Posted By: GreenPaddyvapour barrier under wood floor, consider a liquid DPM - paint it on, then you can glue the timber floor to the concrete.


    Cool, I'll have a look, never heard of liquid dpm before.
    • CommentAuthorGreenPaddy
    • CommentTimeJan 26th 2020
     
    I've used this before (plenty of similar products once you know roughly what you're looking for), to block/reduce the moisture from the concrete, as it hadn't cured long enough. This supplier also has adhesives for gluing the timber floor on afterwards

    www.flooringsuppliescentre.co.uk/products/paints_primers/primers_treatments/wakol_adhesives/5942/wakol_pu_280_polyurethane_primer_dpm_11_kg.html

    I've sort of slightly lost the track of this thread, as it seemed to start off about having a breathing floor, with limecrete, but is now at a fully DPM'd concrete floor.

    Making no comment about appropriateness or otherwise of either approach, as I've no info. on the sub floor moisture levels over time, but is the OP asking the right questions?
    • CommentAuthorMatBlack
    • CommentTimeJan 26th 2020
     
    Posted By: GreenPaddyI've used this before (plenty of similar products once you know roughly what you're looking for), to block/reduce the moisture from the concrete, as it hadn't cured long enough. This supplier also has adhesives for gluing the timber floor on afterwards

    www.flooringsuppliescentre.co.uk/products/paints_primers/primers_treatments/wakol_adhesives/5942/wakol_pu_280_polyurethane_primer_dpm_11_kg.html

    I've sort of slightly lost the track of this thread, as it seemed to start off about having a breathing floor, with limecrete, but is now at a fully DPM'd concrete floor.

    Making no comment about appropriateness or otherwise of either approach, as I've no info. on the sub floor moisture levels over time, but is the OP asking the right questions?


    Hi GreenPaddy, I think I have got lost with it all too, as well as slowly losing my mind:)

    Just to explain then if I may:

    I want to do the best thing for our house, and I do believe in my very limited experience that keeping things as breathable as possible must be the best option for the type of property. (edwardian solid brick semi)

    I have stripped a lot of it back, every old lath ceiling, rotten timber suspended floors, uninsulated concrete floors at the rear, sunken tiled hallway, tanking plaster all gone, with lots of remedial works too - doors, wiring, boiler, ufh etc. (I'm doing most of it myself if I can, getting trades where I've got no chance - roof,boiler,screeding, plastering)

    And now looking at it all with my budget and now only 7-8 months to do it all and move in, I'm a bit intimidated by it all I guess. so Ive been trying to see if I can get a balance with time,cost and what is best for the house.

    So as much as I think the glass/limcrete is the best option, I was questioning how much damage would a standard concrete floor (+ufh) throughout do, seeing as I am going to reinstate the lime pointing and plaster, use woodfibre (and maybe some external eps) - keeping the rest breathable. The concrete could be poured in quicker and cheaper. Wondering if this could be a viable balance of cost, time and moisture control.

    Apologies for the long sprawling reply!
    • CommentAuthorMatBlack
    • CommentTimeJan 29th 2020
     
    Posted By: jfbI went for EPS/concrete floor with woodfibre IWI/lime/limewash in the end. Mostly for cost reasons and a general assessment that it wasn't too damp. Also put french drains round edges where I could. More choice for floor finish a factor as well. I also had a large area to do and used a pump for the concrete pour - would have been a lot more work doing the limecrete floor.
    Has worked very well - a couple of areas with a little discolouration/salts near the bottom of internal wall but not bad.


    What order was your floor build up, and did you have a screed on top too?

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