cracking screed at edges abutting patio doors

31 Aug 2020
Reaction score
United Kingdom
I apologise if this has been posted many times before but I did try and search for the original advice but couldn’t find it
We bought a new build property and the screed is cracking - the builders came, dug it out and relayed it and it crumbled a matter of days later again even in dry weather (not wet conditions outside) they are now saying they’re stumped and don’t know what to do. Please can someone help/advise it’s really getting me concerned


  • 6B023ABB-6EB0-40C2-B720-6A7DB8EB008F.jpeg
    334.8 KB · Views: 312
  • 710C261A-C1B5-47A8-BDE9-21E9D98DB936.jpeg
    266.2 KB · Views: 348
  • B475D0C8-C2C1-462E-B11C-ED1427891DCA.jpeg
    297.7 KB · Views: 308
Sponsored Links
Your Dpm sheet is ripped and there is a void so it needs digging back a few inches. The sheet repairing then making sure no air pockets behind it then fill in with rapid repair.
Sponsored Links
Is this a conservatory?
How high is the door sill above the outside ground level?
There's damp showing on the screed surface.
What's under the membrane?
Hard to tell but the screed looks like SLC? Is it SLC or S&C?
What exactly did the builders dig up - the whole floor?

The membrane is wrongly laid, & appears to be in the wrong position - somehow, moisture is getting under the screed.
The screed is far too thin, & shouldn't have been laid direct on a DPM.
If the whole of the screeded floor is like you show then the whole floor stands a good chance of crumbling.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local