Screed disaster - laid to wrong levels - options?

[amsie]

Hi all,

Without going into all the details, a friend of mine helped me screed my floor on my extension. I was going to do this myself but as he was a plasterer and had done screeds before, I done the mixing and donkey work and he done the screed.

However, and I am baffled how on earth he did this, he laid the screed 40mm out of level. That is, the screed slopes 40mm from one end of the room to the other. Additionally, he started the screed 20mm lower than he should have done.

The area is 3.5 x 5m so latexing to get over this monumental cock up will be expensive. Even adding in Sharp sand I think it would still cost a packet. What options are available to me? Would an SBR screed get over this? Id rather not gun the lot up if possible.

No comments regarding the person in question please, he knows he's cocked up and I know he's cocked up and I don't need reminding on a forum about it. Were not best pleased about the situation, and he has offered to come and help out but i've declined his offer!

Thanks in advance

Paul

 

[dann09]

Whose to say that you wont cock-up the next layer of screed if you didn't know how to lay the original screed? Do you have fresh knowledge, or a new helper?

You must work to a bench mark: your bench mark is, typically, the FFL of the main house.
You must also be aware of the relation of the finished screed to your DPC, and the threshold at the kitchen door.

Stretch a line from your FFL to the threshold and measure the gaps - then come back here.

What material will your finished floor be? Tile, wood, vinyl etc?

 

[amsie]

Dann,

Done all that already, have already mentioned that the floor is out by 40mm, so were looking at 20mm low at FFL and 60mm low at the Kitchen door. Finish will be tiles.

Forgot to add my trade is plumber and before that wall & floor tiler so im used to levelling up screeds with latex but never seen one this much out and didnt ever expect to have one so much out in my own extension.

Paul

 

[noseall]

Short of say double tiling i don't know what you will do other than re-screed.

The whole thing is unacceptable and should be fired up.

 

[amsie]

Cheers Noseall,

So you don't think a 20-40mm SBR Screed will do?

Regards

Paul

 

[noseall]

Cheers Noseall,

So you don't think a 20-40mm SBR Screed will do?

Possibly but it is risky. There ia a chance that it will delaminate and sound hollow.

 

[amsie]

True. I'll have to think about this one.

Thanks for the advice.

Paul

 

[theoldun]

You can safely get down to a modified 12mm thick screed with Sovereign SBR Bonding Agent.
Google Sovereign SBR Technical Information Sheet, read it very carefully and follow their instructions.
Use the cement slurry SBR as bonding coat, and the mix all as stated for 12mm screed. Change your mix when screed gets deeper all as technical sheet.
Do two other things that are not in their technical sheet.
1 With angle grinder, grind 150 to 200 grid in existing screed 6mm deep. On completion ensure all dust on existing screed and in grooves is vacuumed out before applying bonding slurry.
2 Throw a small hand full of PP fibre into each gauge.
Screed will not delaminate or crack if done as above.
Regards oldun

 

[amsie]

Thanks Oldun, that could save me a lot of hassle ripping out the existing screeded floor.

Im gonna try that next week and i'll post back the results.

Thanks again, really appreciated it.

Paul

 

[amsie]

Hi all,

Just wanted to say thanks again to Oldun the screed top been down a few months now no problems it went off as solid as a rock.

Thanks also to Noseall who provided me some good advice throughout the build on the bits I was unsure of.

Cheers again

Paul