Floor tiling advice needed please

[beech1948]

I'm stripping a smooth concrete floor of 50 yr old Thermoplastic tiles which have been stuck down with contact adhesive. Probably the peel and stick type`.

To my surprise the contact adhesive is still "wet" that is not fully cured and is drying rapidly after lifting the first 12 tiles.

Can I just set the porcelain floor tiles on top of this using the normal tile cement or must I remove the contact adhesive first....one hell of a job to do. I have cleared two 12" square areas tonight before leaving work and it took forever even with my Fein multimaster on top speed and the blade at a 70 degree angle or so....removed maybe 80% of the adhesive.

I guess I'm looking to see if I have to clear this before tiling or the job will cost so much it'l just about break even. Its not my usual line of work just trying to help out a very good customer.

Thanks in advance

Al

 

[Doug B]

Can I just set the porcelain floor tiles on top of this using the normal tile cement

You`ll be fine going over the contact adhesive with any normal floor tiling adhesive, if the CA sticks like it normally does it will act as a good sealer for the concrete, but you want an adhesive with something like porcel bond in it if they are fully vitrified porcelain tiles

 

[Noel]

As it happens came across a similar situation some months ago. I lifted a few lose tiles and ensured the rest were firm and laid the new tiles on top using regular tile adhesive (the Bostik stuff in the green bag). All was well. I wouldn't worry about the sticky stuff you've encountered, slap (technical term....) the adhesive/cement on and tile away.
Doug may have a point about the porcel bond, I was just using ordinary ceramic type floor tiles.

 

[beech1948]

My tile shop staff just sucked their teeth and said No when I asked about tiling over the thermoplastic...said it was too shiny to stick.......but your experience contradicts this. Uhmmmmmmm

Al

 

[Doug B]

Al,

This stuff http://www.bal-adhesives.co.uk/products/rapidset will stick to mastic asphalt so I don`t see dried contact adhesive being a problem.

In fact if you look at the product data, in the background & bases table it`s suitable to use to tile over vinyl tiles.

In all the time i`ve used it I`ve never had a problem & I`ve tiled asphalt exterior verandahs.

A thought does cross my mind though, some tile shops only stock fairly limited standard cement based floor adhesives which have quite a limited use, they could be meaning that any adhesive they stock wouldn`t be suitable.

Your best course of action would be to ring Bal technical if you`re in doubt, they are the experts & their adhesive is the only one I`d use if i was tiling on a background I had any doubts about.

 

[beech1948]

DougB,
Many thanks. I've just talked to Bal Tech support and looked at the product data sheets from Balset Rapid. They recommend the Rapid product for tiling over the shiny Thermoplastic tiles providing they have a bonding agent applied first.

Interesting but they recommend ordinary Balset to tile over the dried contact adhesive, with any thicker patches removed.

Seems I need to choose my surface -themoplastic tile or dried adhesive and get on with it.

Many thanks for the prompt Doug.

Al

 

[beech1948]

Just thought I would close this out with the end story.

I removed the 28ftx18ft area of thermoplastic tiles. A hard and heavy task but made easier with a spring steel floor scraper.

I spread a very thin layer of Thinners Type 3 ( boat anti fouling remover) over the adhesive, donned my newly bought anti-organic vapours mask and goggles and after 2 hrs of waiting I used the floor scraper to get 85%+ of the adhesive off the floor. Only took an hour and it dried overnight. I kept a fan blowing overnight out of an open window to remove any remaining fumes.

Next day I simply applied the Balset and started tiling or rather my sub contractor tiling expert did......turned out really good.
Floor has gone off now and we can carry on with painting the walls.

Thanks to you all

Al