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Ask your QuestionMy kitchen floor has developed bumps. There is a concrete base which appears intact but a new (4 yr old) screed has cracked and 'erupted'. I have had it checked for damp and a builder has looked at it too and can't identify the cause.
Asked by Anne on 15th Oct 2020Best Answer
"Need to lift the floor ,brake the old concrete, screed again and lay a new floor."
Answered on 15th Oct 2020 - Member since Oct 2020 - report"Hi the floor screed seems to have blown. It happens if there is air bubbles still in the mixture, and when it gets warm and cold, the air weakens the middle it can take days to years to cause a problem"
Answered on 15th Oct 2020 - Member since Oct 2020 - report"It’s sounds like the latex could of blown by the sound of it, could be that whoever latex the floor didn’t prime it"
Answered on 15th Oct 2020 - Member since Oct 2019 - report"The cause could possibly be that the subfloor wasn’t primed before the screed was installed. This would then crack and break away as not bonded to the concrete subfloor."
Answered on 3rd Nov 2020 - Member since Oct 2020 - report"Presumably, the screed has been made weak (as in cement ratio ) and has cracked
overtime becoming uneven."
"hello to understand where the problem comes from it is good to do a test, that there may be gaps from below, and from it you create lumps and cracks, and from somewhere there may be moisture and it does not appear"
Answered on 15th Oct 2020 - Member since Jul 2020 - report"If it has 'erupted' or blown then it simply needs to be taken up.
It can then be established why it blew. It could be one of several reasons:
1) it wasn't primed first
2) it was laid when the floor was too damp
3) the wrong 'screed/smoothing compound' was used.
Caveats: someone else might add another reason but those 3 are the most common"