screeding advice please

[saintdom]

evening all

i have a query which is not really tile related but you guys have always come up with very good answers so here goes.

my inlaws had a double garage built with a flat roof which was beam and block, the guys then just screeded it and tiled . well guess what it failed miserably, water pouring into the hall way, tiles lifted and screed turned to dust (was only about 15mm deep

anyway they have moved to the states recently and asked if i could find someone to check it out and find what the best options.

some people have told me to membrane and screed no less than 70mm, leave for a day a mm which i sort of knew about

others have reccomended a concrete slurry , bitchumen, prime, screed.

could someone on here please point me in the right direction, i cant find a clear answer anywhere. the roof will eventually be re tiled by myself

if anyone has any ideas id be most grateful

cheers

dom

[jay]

hi whats the make up of the roof ( cement sheet steel ect)

[cuttintiles]

i would check out a product called Mapelastic or Mapelastic smart.

you will need to take it back to the beam and block to sort it!

best wishes

[saintdom]

hi

the only info i have been given is that its concrete beams with block in between.
im sorry im no builder and as the old screed is still down i havent even seen it yet. i do know there is a fair bit of movement

all i can tell you is there are some pretty nifty stalectites hanging from my bro in lawsa surf board

[jay]

need more info let us know when you find out the movement will be an issue

[cuttintiles]

if you go back to block and beam there should be no movement in that structure.

then apply either mapelastic or mapelastic smart (its a cenmentous waterproofer)

then if i am not mistaken you can apply tiles to it, that said you would need to check the situation with Mapei!

but they sell it as a tilable tanking system for swimming pools!

best of luck!

[Phil Hobson]

15mm is way to thin for any sand and cement screed, Ajax is your best man to ask

[saintdom]

cheers cuttintiles

if i scrape back the old screed and get it back to the original block and beam wont it be a bit rough or uneven to just roll on mapelastic and tile straight over, would i not need a screed down to get a flat level

cheers

[cuttintiles]

mapelastic is a "sort of screed come render" mapelastic smart is acementous paint on thingy.

my money is on Mapelastic.

call mapei, they will give you the low down and you can get it from tile giant... a forum sponsor.

[saintdom]

cheers chaps

much appreciated