Plastic overlay ufh!!!! - Tile Advice

[Bopster]

well that’s not good, kitchen I started this week I was supposed to be installing electric ufh, now the customer has given the job to the plumber who is putting down this crappy plastic system with no room control, just a trv off the heating system!!!
As I’m doing the floor tiling looks like i now need to Slc the floor instead of ditra matting the plastic boards will Be screwed down to the concrete base.
Which slc would you guys recommend, the boards are 18mm thick

 

[Uheat - Jake]

This is a ProFix system (Ultra Low Profile Underfloor Heating Panels - Floor Insulation Panels - http://www.profixpanel.co.uk/profix-panel.php) which is recommended to be used with there own SLC compound which should be supplied along with the panels. If you don't use there own SLC then they have said a Mapei Renovation screed can be used.

 

[Bopster]

Ok so unsurprisingly the plumber didn’t supply the slc, I’m happy to us the mapei renovation screed. Floor area is 10sqm and I guess will need 20-25mm depth so 12 bags?
Also it states walk on hard 4-5hours, presumably that’s at a thin depth. Would it be safe to tile the following day if done in a morning,

 

[Uheat - Jake]

ProFix state that either 15mm or 18mm of SLC is suitable to go on these panels. Walk time and tiling time would be what Mapei recommend for that product, just make sure the UFH isn't turned on before pouring the SLC or it's not used to help dry the SLC out

 

[Bopster]

Thanks for that Jake, out of interest the plumber doing this install isn’t using a manifold or separate control to the rest of the house. Just connecting to the existing heating via a trv which will be buried behind one of the new tall larder housings in the kitchen.
I’m no ufh expert but will this work as the floor will only be heating for couple hours in morning and evening and have no real heat control?

 

[ShaunCorbs]

No that’s a big no no needs it’s own separate controls and really it’s own run from the boiler as with the set up you describe the floor will be around 30-40 Dc also will have to come on with the heating

Needs a mixer else the floors going to get too hot will cause problems with your tiles

 

[Waluigi]

A Plumber suggesting that isn’t a Plumber let alone Heating Engineer.

 

[Bopster]

His words to me was it’s the cheap way!! He was meant to do it last week, then twice this week now it’s maybe next Saturday afternoon or week later! He doesn’t even reply when u leave messages on his phone. He’s just installed an outside oil boiler for them, I wouldnt like to guess what maybe wrong there.
I’m going to have to speak to the customer and raise my concerns about what he’s planning on doing, if they still go ahead I’ll refuse the tiling job as it’s not fit for purpose and the tiling will fail over time.
I don’t want to offend my customer and them thinking I’m trying to push him out but surely what he’s proposing is incompetence. Once this project is finished there’ll be further works refitting cloakroom and bathroom which I’d like a shout at

 

[Boggs]

“Don’t worry love, I do it the cheap way, it’ll be fine”

 

[Waluigi]

Bopster, I would try to be as diplomatic as possible and make it your duty to inform them.

Not only are you saving your customer from a potential disaster, you also save face when your tiling doesn’t fail due to a poorly installed UFH system.

 

[Sean Kelly]

I walked away from a job last year when the builder attached plastic ufh pipes to a radiator and then buried the pipes in the floor.

 

[Bopster]

Well the deed has been done and I’ve informed my customer of the issues, they were really grateful and have put the issue to the plumber concerned in writing. They have stated to him to do the job correctly or walk away and I’ll do it for them. I still dread to think how much more he will try to charge, though this shouldn’t be my concern if they are happy to pay
Who Thinks I may have upset the plumber with this lol

 

[Waluigi]

You’ve done the right thing. No Plumber worth his salt would be running an UFH system off a TRV. The idea is just demented.

Being honest, why on earth would the customer be entertaining the idea of using that guy, now that you’ve pointed out the flaws in his methods. Hopefully they trust in what you’ve said and make the right decision

 

[Boggs]

Well the deed has been done and I’ve informed my customer of the issues, they were really grateful and have put the issue to the plumber concerned in writing. They have stated to him to do the job correctly or walk away and I’ll do it for them. I still dread to think how much more he will try to charge, though this shouldn’t be my concern if they are happy to pay
Who Thinks I may have upset the plumber with this lol

It’s ok I know where you live.....

 

[Bopster]

I know they have trusted me on this but I have backed up my case by attaching in my email the manufacturers installation video showing what’s required and another link to an manufacturer showing why and how each part is required.
I’ve well and truly shot his method to shreds