First time poster so apologies if this is in the wrong place.

i have recently moved into a first floor flat and upon pulling up the carpet in my hallway I’ve found a fairly wide crack in the screed. I’m wondering firstly,  if this is anything to be concerned about (structurally) and secondly, what’s the best way to repair? I plan to put down new carpet once sorted. 
crack seems to be through the full depth of the screed at least in places but stable and level on both sides (maybe 1mm difference between sides). Crack is 4/5mm wide, on top of underfloor heating and the flat is a fairly new build around 15 years old. No other cracks in walls or skirting.

Edited June 29, 20251 yr by Ma3667
Added context

Hi. 
That’s just a shrinkage crack in the screed, not structural as the structural subfloor will be below the insulation under the screed.

 

Just buy a small 10kg bag of flexible tile adhesive and make it into a mix like soup. Pour that in, leave for an hour, then scrape flat with a metal decorators scraper. End of problem. 
 

Wet the joint before putting the adhesive in, so the porous suction of the screed doesn’t dry it out too quickly. 

 

You won’t need 10kg btw, but that’s the smallest bag you can buy. 

Thanks Nick, appreciate the advice

2 hours ago, Ma3667 said:

Thanks Nick, appreciate the advice

No worries. Just scrape the joint and hoover out any loose debris / dust before filling it back in.

 

This is just cosmetic tbh, and the crack from the doorway corner across is pretty much predictable.

 

Zero drama here