[mmc66]

I will be installing an 8x12 custom mural. The substrate is drywall over block. The client wants it installed so it could be removed (not easily) in the distant future and reset at another location without damaging the individual tiles. It is considered a work of art and falls into a different category than field tile. My plan was to attach CBU using countersunk Tapcon screws placed along grout lines and areas where they can be accessed by removing the grout, and then provide a diagram of their location for future removal.

Two primary questions:

(1) Are mechanical fastener (blue screws) enough to hold CBU to a block wall for a large tile mural with heavy tiles?

(2) Some of these tiles are huge. Should I switch to medium-set for tiles that weigh as much as 20lbs and 17” diameter? They are high-relief, not perfectly flat and have deeply recessed areas on the back that prevented them from cracking when being fired. Do I fill them with medium-set to be flush with the rest of the tile before setting, to create one bonding surface?

 

[mikeswoods]

There is a tile forum that may help if no one here has an answer,www.johnbridge.com

Good luck,Very unique situation ,I have no suggestions.

 

[Cdat]

Make a medallion totally seperate from the wall surface. Create a back plate to mount it on. As for what the wall will hold, I'd be anchoring it to the block with some heavy duty bolts. Depends on the total size/area of the 'art form'.

 

[Aframe]

If they really think they will move it at some point, I would consider making individual panels (2'x3'?) that hang on wall surface like a large picture. Add clips or maybe twist locks that will keep the panels in line with each other. You could locate/map them as you described.

Digging for screws in grout lines would be awful. The backer will have to be rigid enough to keep its form while being removed and I can not see that happening with just a CBU panel

 

[mmc66]

This is 8 x 12 feet and runs floor to ceiling and wall to wall at the end of a hallway. It is a very old commercial building, plaster/drywall over block. Making one huge panel to mount is virtually impossible. Making a series of panels seems reasonable. But, the seams of the panels would have to align and match solidly and be positioned behind tiles and not grout lines. If disassembled, everything that straddles the seams would be ‘sacrificed’. Not damaged, just popped off and removed.

I’m wondering if making separate panels and grouting them as one might be a slow-motion recipe for eventual cracking. Unless there is a way to make 3, 4x8 panels that were stable enough when mounted to allow stable grouting across them. Would just not want the seams of the panels to line up with grout lines. Also, this is not a grid, but contains pieces of varying sizes and dimensions that go all over the place.

Still leaning toward screwing durock to the wall with Tapcons and giving them a treasure map of the screw pattern.

 

[Tscarborough]

If it may be moved, then the underlying structure must be built as a unit that is capable of being moved as whole. Unless by some miracle of design it is able to be broken into smaller pieces, i.e. linear joints, then it is no problem.

 

[Aframe]

"Still leaning toward screwing durock to the wall with Tapcons and giving them a treasure map of the screw pattern."

Your durock base won't be one piece anyway, so without any type of frame it won't be stable enough for them to move it.

Even if the successfully were able to locate screws and remove it from the wall as one panel, Would they be able to get it out of the space/building.

If your going to try it, make up a sample with one 3x5 sheet of durock and some tile leftovers. Wait one week and then have a friend use your treasure map to locate screws and reinstall it on another wall.

 

[mmc66]

Thanks to for submitting suggestions. Sorry to disappear. Got distracted by other jobs. The final approach to this dilemma involved convincing the client that making the mural able to move was going to be extremely difficult, expensive, and might compromise the piece.

We agreed to go forward with a standard installation and worries about relocating it will have to be solved by future generations.

The wall turned out to be block with scratch and plaster coating. I'll be installing backerboard with thinset and tapcon screws to prep the wall, which is an interior wall. No need for water or vapor issues.


Thanks again.

 

[angus242]

Thanks for the update and glad to hear it has worked to your favor!

Good luck the rest of the way.

 

[reveivl]

Yeah, can you imagine the call back in ten years? " I can't find the screws!"