Problem with Mapei Renovation Screed and Wunda Overfloor panel

[DHTiling]

Hi..

Is there any deflection under the panels?

Was the Renovation screed mixed with the correct amount of water.?

Was the renovation screed laid to min 5mm depth ..?

Lastly , is the heating on. ?

 

[Ajax123]

Hi Ajax123 and thanks for your reply. I will take some photos

just thinking ahead, once the air pockets are resolved, if there are areas where the floor levels are still not right for laying our laminate floor tiles, can further layer of screed be laid on top?, should more primer be applied?

yes and yes but the primary issue is whether or not the Mapei gear is suitable for the application. You could end up just throwing good money after bad and still have a system that is not suitable. You need a conversation with Mapei technical before doing anything further. The "air bubbles" are classic symptom of reaction between hydroxide and alluminium. Pics will confirm if this is a correct diagnosis. N further reaction will occur once the screed has hardened and dried.

 

[Clifflev]

i spoke with the mapei technical guy today. i explained about the Wunda under floor heating product (the overfloor system) and that it has an aluminium top to which he acknowledged he knew the product and what i was referring too. I explained the air pockets with cracks and that they had occurred in a few areas and he said its likely happened because the screed is too thin in those areas. He agreed an extra screed can go on top but must put down the Mapei Eco Primer Grip first - he said the primer was quick drying.

I'm pleased the mapei guy knew the product i was talking about and gave me no reason to be concerned that we have used the wrong mapei products on the Wunda overfloor heating boards with aluminium top.

My view is that an extra screed layer is needed as i recall counting 14 bags of renovation screed which covers 84m2 at 3mm thickness whereas i have 75m2 and needs 5mm thickness.

I'll speak with the flooring company tomorrow and see what solutions/options they propose as they have to lay my new laminate flooring and do a proper job - after all I am paying them money to do this!

 

[Clifflev]

Hi All

Just to give some positive feedback. Had a few phone conversations with Mapei Technical support between xmas and new year, and to my surprise they made the trip down from Birmingham to my home in Hertfordshire to see what the cause is with the screed (I didn't realise they look at these forums!)

The promptly arrived when they said they would (approx 3 hour trip!) and confirmed that the screed was applied too thinly and that the primer wasn't given enough time to dry - this is what many areas had "blown" and not adhered to the subfloor. They also waited for the person who did the screed to advise him how he should correct the issues which the floor company are now putting right

So i just wanted to say a *big* thankyou to the tech guys from Mapei for taking the time to understand the issue and coming all that way to see us and giving us reassurance that it can be resolved 🙂

Regards,
Cliff