Cracked red screed ??

Search the forum,

Discuss Cracked red screed ?? in the Australia Tiling Forum area at TilersForums.com.

L

lewie

TF
0
111
Seaton
I've been asked to tile what looks like a cracked red screed. It could be some sort of water proof membrane and is about an inch thick which has been laid over the original floor. The building is hundreds of years old. It's mostly solid although it's fair to say that some of it is 'floating' where it's cracked although it's not disintegrating.

My thoughts were to tank the cracks and then over lay with no more ply with flexible addy. Seal the joints and then tile.


The alternative would be to use a decoupling membrane and then tile.

Any thoughts/advice ?

Lewie
 
Last edited:
Sort by date Sort by votes
A

Ajax123

TF
Esteemed
Arms
931
1,213
Lincolnshire
Based on your description it could be a magnesite screed... Don't see them often these days. If it is it will be red right through (some were green) and they were used up to about 25years ago especially in old council properties. They don't stick to concrete hence they can delaminates and crack. You will find it almost impossible to stick anything cementitious to it and most primers will fail to work as well. Best thing to be done if it is magnesite is break it out and reinstate it with something else.
 
Upvote 0 Downvote
W

White Room

Ajax123 said:
Based on your description it could be a magnesite screed... Don't see them often these days. If it is it will be red right through (some were green) and they were used up to about 25years ago especially in old council properties. They don't stick to concrete hence they can delaminates and crack. You will find it almost impossible to stick anything cementitious to it and most primers will fail to work as well. Best thing to be done if it is magnesite is break it out and reinstate it with something else.
Click to expand...

In about 43 years in the game i have never seen these screeds laid...
 
Upvote 0 Downvote
S

Stef

Ajax123 said:
Based on your description it could be a magnesite screed... Don't see them often these days. If it is it will be red right through (some were green) and they were used up to about 25years ago especially in old council properties. They don't stick to concrete hence they can delaminates and crack. You will find it almost impossible to stick anything cementitious to it and most primers will fail to work as well. Best thing to be done if it is magnesite is break it out and reinstate it with something else.
Click to expand...

Alan I had one of these a few years ago in an old council property, it was a really dark green almost black & had a few cracks in it, I gave it a couple of whacks with a hammer & it all lifted out in sections.
Cleaned up the floor & levelled it out with renovation screed.
At the time I thought it was a tar like substance.
 
Upvote 0 Downvote
A

Ajax123

TF
Esteemed
Arms
931
1,213
Lincolnshire
Stef said:
Alan I had one of these a few years ago in an old council property, it was a really dark green almost black & had a few cracks in it, I gave it a couple of whacks with a hammer & it all lifted out in sections.
Cleaned up the floor & levelled it out with renovation screed.
At the time I thought it was a tar like substance.
Click to expand...

Yep that sounds like magnesite. They were generally either green or red. I beleive they were actually banned or at least fell from grace about 25 years ago.they were generally used in council properties but I have seen one or two in private builds.
 
Upvote 0 Downvote
A

Ajax123

TF
Esteemed
Arms
931
1,213
Lincolnshire
Stef said:
Alan what was this actually used for at the time?
Click to expand...

It was used as a simple levelling screed. It was one of the first thin screeds available. If you have a moisture meter (electronic style) it will show up as off the scale wet cos it is conductive. That is one of the identifying tests.
 
Upvote 0 Downvote
L

lewie

TF
0
111
Seaton
Apologies. Long day yesterday and completely forgot. Here are some pics red screed1.jpg red screed2.jpg red screed3.jpg
 
Upvote 0 Downvote
A

Ajax123

TF
Esteemed
Arms
931
1,213
Lincolnshire
Upvote 0 Downvote
A

Ajax123

TF
Esteemed
Arms
931
1,213
Lincolnshire
lewie said:
What's your thoughts on tiling it ?
Click to expand...

Personally think it dangerous. It's thin, bonded so may get damp. It's also failing and if it's drum my it will fail further. I would recommend removal and reinstatement with an equivalent depth of suitable insulation (marmox etc) and tile that instead
 
Upvote 0 Downvote

Reply to Cracked red screed ?? in the Australia Tiling Forum area at TilersForums.com

There are similar tiling threads here

Tile Marble Granite
    • Like
  • Sticky
  • Question
Water damaged shower repair
Water Damaged Shower Repairs Shower tile repair – water damage – tile waterproofing Do you have shower leakage that goes downstairs leading to either your main floor or basement? Read this blog...
Replies
0
Views
2K
Tile Marble Granite
Tile Marble Granite
Posting a tiling question to the forum? Post in Tilers' Talk if you are unsure which forum to post in. We'll move it if there's a more suitable forum.

Advertisement

Birthdays

Top