Scratch Coat Questions - Concrete, Stone & Masonry - DIY Chatroom Home Improvement Forum

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Concrete, Stone & Masonry


Thread Tools Display Modes
Old 10-23-2013, 08:42 PM   #1
Join Date: May 2011
Location: Vancouver, Canada
Posts: 39
Rewards Points: 29

Scratch Coat Questions

This pertains to applying stone veneer to the fireplace surround sheathed in concrete board.

When making up the scratch coat is there a time limit with respect to how fast should the stone veneer should be laid before I lose any structural value from the mortar to scratch coat adhesion.

Because the stone lay up will take me a few weeks I was thinking that the scratch coat drying completely may have some adverse affects.



Paul8434 is offline   Reply With Quote
Old 10-26-2013, 08:13 AM   #2
Cruising into the sunset
JulieMor's Avatar
Join Date: Apr 2012
Location: Punta Gorda, FL
Posts: 611
Rewards Points: 518

I'm in the middle of doing the same but outside. Everything I have read from the stone and the mortar manufacturer say the scratch coat should be allowed to set for at least 24 hours. There was no limit to how long it can sit after that before setting the stone. Some suggest using a spray bottle and wetting the surface of both the stone and scratch coat before applying the mud and setting the stone.


JulieMor is offline   Reply With Quote
Old 10-27-2013, 06:22 AM   #3
Join Date: Jun 2009
Location: atl & hilton head
Posts: 4,607
Rewards Points: 4,796

wetting an existing surface helps prevent existing dry surface from sucking the needed water out of the freshly applied ' stuff,,, were that to happen, it would weaken the new 'stuff ',,, there are specific bonding mtls but few actually use 'em,,, the condition you want is called ' surface saturated dry ' - the surface's wet no standing water's evident... obviously MUCH easier on vertical & overhead surfaces.

we usually use a water hose + leaf blowers for flat work
stadry is online now   Reply With Quote
Old 10-27-2013, 07:05 AM   #4
ddawg16's Avatar
Join Date: Aug 2011
Location: S. California
Posts: 11,481
Rewards Points: 2,116
Blog Entries: 2

I'm not the expert....but have done it.....after a couple of pieces it becomes obvious what is the right amount of water.

isitreallyconc covers it pretty good....

Me? I use a hand spray bottle. I get the spot I'm about to cover wet...but not so wet that it runs down. I find that a moderate first spray before you start mixing up your mortar....then followed up with a as needed spray seems to work well....The color is a good the surface starts to dry, it gets lighter....

The key is that you don't want it so wet water runs down. What is really cool is that you can experiment with the water seeing how much it takes before you do the actual mortar....if you put too much...dab it off with a towel....or just let it air dry....

Don't be afraid of will get the hang of it quickly....

One thing you don't want to be lazy with....scraping out the excess it before it starts to set.....since us DIY guys take for ever to do these kind of jobs....clean as you will be glad later.
Even if you are on the right track, you will still get run over if you just sit there.

My 2-Story Addition Build in Progress Link ... My Garage Build Link and My Jeep Build Link
ddawg16 is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Hardwood refinish questions, removing part of old coat only before re-coating? Dimeron Flooring 2 05-17-2013 07:54 PM
Need advice using Insl-x Cabinet Coat ladydub Painting 13 06-29-2012 03:22 AM
Fireplace Reno - Scratch Coat Branden Building & Construction 7 01-05-2012 08:09 PM
Please help (again):Why is my SW Pro Classic paint sagging on the second coat? Fun2Learn Painting 7 12-05-2011 10:12 AM
Two questions about Terpolymer Elastomeric Waterproofing Paint ohman Painting 2 11-10-2011 06:04 PM

Top of Page | View New Posts


Search Engine Friendly URLs by vBSEO 3.6.1