tiling over paint (yet again) - TilersForums.com

[doug boardley]

tough one goatboy, tempted to say "when it's dry lol" but that's not an answer. If you have access to a dehumidifier, stick that in the room (make sure doors and windows are closed) for 4 or 5 days.

 

[goatboy]

and without a dehumidifier? just havnt got one and i remember at our last rented place the owner did that when he rendered the bathroom and it caused the render to crack as it was drying too fast :S

 

[doug boardley]

are you sure it was a dehumidifier? a heater will crack fresh render, (fan or convection), a dh can be hired from HSS or a plant hire depot local to you

 

[goatboy]

positive because I had to empty it about 5 times a day when it was first put on lol

 

[White Room]

Can you leave the render for a couple weeks for it to cure

 

[goatboy]

yes can leave it for as long as it takes but was wondering how long it takes because with render then plaster on top it takes near to a month+ was wondering if it would be quicker with just a cement render.. and basically you can use a dehumidifier but it cant be in close proximity to the plaster.. same with a heater.. in a room that is 1m x 2m that is near impossible... if you put a heater or dehumidifier next to a wall and that bit dried out faster than the rest then it would cause it to crack.. also wondering if the cement render should have any lime in it to perhaps stop any cracking or is that me just going ott?

 

[doug boardley]

I'd use a rendering sand mixed 4.5:1 with cement, rather than using lime, I'd use cementone waterproofer as a plasticiser(no skimming, tile straight onto render)

 

[goatboy]

ok well its definatly not comming off the wall as i said earlier its going to be having a mesh backing bolted to the wall for it to adhere to.. just hoping that is enough not to have to blast the paint off that is behind it.. will be grinding out some of the mortar between the bricks to give it an even better key... only want to be doing this the once lol

 

[White Room]

Do a scratch coat first on eml then render

 

[jay]

the renderer should put a dash coat on first to provide a key for the render at least 95% of the paint should be removed and depending on how thick it needs to be let the render dry slowly some old bricks suck the guts out of render and you need to wet render as it cures norm after one days drying get a bucket and a drinking cup and pour water at the top of render letting it run down face of render also were render meets floor a small v should be left at base to stop any rising damp :8: also dont recomend ataching expanding metal over painted bricks as render will only be held by whatever you use to fasten metal with