Membrane over concrete w/o cracks

[pitterpat]

How many are using some type of membrane over concrete that does not have cracks? What kind and why?
Pat

[Ken]

I use different products, what ever the store provides. Whatever the case, its always been on concrete with or WITHOUT cracks, basically because the architect spec'd it or the store I did the work for sold the client on it.

I've use Laticrete 9235, TEC Triple Flex, along with DALtile CIS as anti fracture membranes.

I think its cheap insurance if you think about it, in case the concrete ever breaks. I live in Michigan so there is a LOT of expansion and contraction to be expected. I'm not sure how many times it's saved us from hairlines telegraphing though the face of the tile, but i'm sure quite a few.

[T_Hulse]

I use Ditra. A crack-free slab is just one that doesn't have them yet.

[Ken]

I didnt think ditra had crack suppression support?

[Dave Taylor]

From Custom's web site.......
*************
RedGard®
Waterproofing and Crack Prevention Membrane
*****************

I have associates who swear by this product when used as (Kurgon says) " as insurance" before laying tile on a crack free slab.

Tom H is right..... a crack free slab is just waiting (itching) to fracture somewhere, sometime.

Ceramic coverings I've seen over a slab (where this product has been used) look fine and --so far-- remain crack free.

Other paint on membranes advertise crack suppression properties too.

Hope this helps

[ceramictec]

Hey Dave,

RedGard is a good product but CBP makes a cheaper crack membrane only without the waterproofing properties. its called "FractureFree".
Hamilton turned me on to this a while ago and I like it.

there's also Mapei 315 & Noble CIS

[matman]

Hi Pat,
I just installed a crack membrane over a crack free slab, cheap insurance. At the least I think you should offer it. You don't want a crack showing up a few years from now and your customer claiming you could've done more, eh?

[284]

I was wondering about the insulating properties of putting one down on slab on grade.

[ceramictec]

I don't think a liquid membrane would offer any insulating properties.
on slab it would probably be zero.
ona wood subfloor it would have to be done underneath with insulation as the norm.

[T_Hulse]

Kurgon crack isolation is intended for cracks that have already happened, which is not really what we're talking about. Ditra is advertised as an uncoupling membrane, which isolates the tile from all kinds of movement stresses.

[Scooter]

Everytime. But we live in CA where there is earth movement.

[nforcer2]

How about a mortar that meets the standard for us as an antifracture membrane?

[Dave Taylor]

Robert G said: How about a mortar that meets the standard for us as an antifracture membrane?

Splain' that one to me please Bob. I think I just fell of this thread train and I'm workin' my way back on :---)

[INtilesetter]

Going to try some new laticrete 125 thinsette on thursday,usually use ditra, but want to give this 125 a try.........1 step process with the 125

[tilemanct]

Whats the price per bag of the 125? The TEC stuff was priced into the stratsosphere!