Hairline cracks in new plaster

Discussion in 'Builders' Talk' started by shefmarkh, Nov 29, 2017.

  1. shefmarkh

    shefmarkh New Member

    Hello,

    I had some walls replastered (in some places just reskimmed, and in others plastered all the way up from the brickwork). Now I am soon to paint the room and on close inspection I see a lot of very thin hairline cracks which run approximately horizontally across the walls (mostly no more than half length). They are so thin you cannot see them unless you look at the wall from around 5-10 cm away.

    Is this anything to worry about or is normal for new plaster?

    Thanks,

    Mark
     
  2. shefmarkh

    shefmarkh New Member

    Can add some photos this evening if that helps!
     
  3. That might - we love photos...

    Is there anything in that wall that could make this happen? Are there plasterboard sheet joints where these lines are?

    Were there any cracks/joints there before it was skimmed?
     
  4. KIAB

    KIAB Well-Known Member

    Heating!

    Suction in brickwork!
     
  5. nigel willson

    nigel willson Well-Known Member

    Dried too quick!
     
  6. shefmarkh

    shefmarkh New Member

    Photos attached.

    The work was done end of August, so heating would not have been on. Obviously it is now we are into winter. Some new cracks have appeared in last few weeks.
     

    Attached Files:

  7. shefmarkh

    shefmarkh New Member

    Based on the photos is this a major worry? If so I suppose I should contact the firm and ask them to take a look, though if it just dried too quick is not really their fault? But its not mine either because I was not running heating until October (work was done in August), and they did not tell me to keep heating off for months on end.
     
  8. shefmarkh

    shefmarkh New Member

    "Is there anything in that wall that could make this happen? Are there plasterboard sheet joints where these lines are?"

    The wall has had a damp proof tanking system put in up to 1.4 m. The cracks are both below, at and above this height. So it does not appear
    to correlate.

    "Were there any cracks/joints there before it was skimmed?""

    None at all that I can recall.
     
  9. I'm stumped, Shef. I don't really know enough about plastering to say much more.

    Also I can say is, it's nothing you've done.

    Was it particularly warm and dry in August (I can't remember that far back...)? If that was the cause - it drying out fractionally too quickly - then I think that's probably a good thing 'cos it's nothing more sinister!

    I would certainly contact them and ask about the best way to fill these cracks successfully. Personally I would like to do something to 'bond' the crack sides together first before filling. Not sure what to use, tho'...
     
    KIAB likes this.
  10. KIAB

    KIAB Well-Known Member

    Definitely get them back to have a look.

    You can get cracks when the block/brick, some (some bricks are vampires) sucks the moisture out of the plaster, this is solved by priming the wall before plastering with pva diluted 4 to 1.
    There is a chance the plaster might have failed & not properly bonded to the brick work, so it part company with the wall.
    Use to use Knauf high suction pimer some years ago to combat the high suction of some brickwork.
     
  11. shefmarkh

    shefmarkh New Member

    ok thanks, yes have sent all the pictures to the firm and await their advice!
     
  12. shefmarkh

    shefmarkh New Member

    So the plasterer said these cracks are common when drying, and should be covered easily with a base paint coat. They advised filling lightly with Easifill if they still show through after that.
     
  13. KIAB

    KIAB Well-Known Member

    Total bs, yes you can get fine hairline cracks, but those ain't,background has sucked the moisture out of the plaster too quickly, drying too quickly due to heat,even using out of date plaster can causes problems.
     
    GoodwithWood, stuart44 and facilities like this.
  14. facilities

    facilities Guest

    June & July were the hot months this year DA, I remember that cos I was in your lovely neck of the woods in August for a couple of weeks and the weather could have been a lot better
     
    Deleted member 33931 likes this.
  15. koolpc

    koolpc Well-Known Member

    Plasterer did a naff job.
     
  16. stuart44

    stuart44 Active Member

    Spot on. Being a bricklayer I'm not the best spread in the world, but I have learnt a few things about suction and old plaster over the years. Can remember doing a few plastering jobs when I was a lot greener and thinking I'd done a half decent job, and then suddenly all the cracks started appearing as fast as i could trowel them away.
     
  17. CGN

    CGN Well-Known Member

    Any hollow sounds when you tap the wall?

    When they re-plastered from the brickwork, did they dab on plasterboard or wet plaster with a backing coat?

    What did they plaster over on the re-skim parts? Was it wall papered before, any silk paint etc?
     
  18. Dr Decorator

    Dr Decorator Active Member

    Looks to me like it’s been skimmed over old lath and plaster which is dead!

    Or unstable substrate underneath
     
  19. shefmarkh

    shefmarkh New Member

    "When they re-plastered from the brickwork, did they dab on plasterboard or wet plaster with a backing coat?"

    I'm afraid I have no idea, beyond knowing up to 1.4 metres cementitious tanking was added.

    "What did they plaster over on the re-skim parts? Was it wall papered before, any silk paint etc?"

    Matt emulsion paint I believe. My understanding is the re-skim was only done on a small fraction of the wall, the rest
    was fully replastered to full ceiling height (due to the old plaster being damaged from a water leak, which was first fixed
    my plumber).

    "Any hollow sounds when you tap the wall?"

    No it doesn't sound any different to any other wall I have tapped. This would be a very obvious sound difference to hear (i.e not so subtle an amateur might not spot it)?
     
  20. Iron_Mike

    Iron_Mike Active Member

    You need to get them back fella
     

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