Hearth Rebuild - Any Tiling Experts?

[Waulie]

I'm getting a new stove real soon and need to update the R-value of my hearth. I discovered my current hearth consists of about 1.5 inches of mortar and ceramic tile, which has a shockingly low R-value.

So, I'm planning on adding 0.5 inch Durock and new tile. I'm wondering how I should fix the Durock to the exisiting tile. On another thread, BeGreen suggested I drill into the tile/mortar and set anchors which will accept the screws for the Durock. While I'm sure that will work, I was wondering about just using thinset between the old tiles and the Durock. Wouldn't that be just like tiling in reverse? I could place heavy weights on the Durock until the thinset dried.

Any opinions?

Thanks!

 

[bluedogz]

So you'd want the thinset to bear the weight of both the Durock AND the new tile?

This would expose you to the risk of the slightest error on your part in choosing, mixing, & applying the thinset would bring the whole thing crashing down.

+1 vote for the anchors.

 

[Waulie]

So you’d want the thinset to bear the weight of both the Durock AND the new tile?

This would expose you to the risk of the slightest error on your part in choosing, mixing, & applying the thinset would bring the whole thing crashing down.

+1 vote for the anchors.

Sorry, I should have been more clear. This is only going on the floor not on the walls. So, nothing can crash down. My only concern is if I would get a solid enough bond so the durock can't move and crack the new tile.

 

[scotvl]

Yes you can use thinset to attatch the durarock, just make sure it's good thinset. Tell the clerk at the tile store what you're doing and he will give you the right one.

 

[Wade A.]

Shoot....you could probably just dry bond it and it wouldn't shift in a thousand years, but, yeah, thinset: Not so much for adhesion, because you'll have no shear force to counter, just to provide an even bed to prevent cracking. If you did want to screw the durarock down, you could shoot your screws into the (presumed) mortar joints of the existing tile. It would take some precise measurements to hit those, but the mortar is soft and will bite on a screw pretty well. You can also just sink screws through the durarock at random points until you find a mortar joint. (You'll not have to wonder if you've found a glazed tile instead..you'll feel it) . Extra holes in the durarock won't make a difference, they'll be mortared over for the new tile.

 

[Waulie]

Shoot….you could probably just dry bond it and it wouldn’t shift in a thousand years, but, yeah, thinset: Not so much for adhesion, because you’ll have no shear force to counter, just to provide an even bed to prevent cracking. If you did want to screw the durarock down, you could shoot your screws into the (presumed) mortar joints of the existing tile. It would take some precise measurements to hit those, but the mortar is soft and will bite on a screw pretty well. You can also just sink screws through the durarock at random points until you find a mortar joint. (You’ll not have to wonder if you’ve found a glazed tile instead..you’ll feel it) . Extra holes in the durarock won’t make a difference, they’ll be mortared over for the new tile.

Sounds good. I guess I'll do thinset and some screws right into the mortar joints. They're actually pretty fat and in straight lines so I should be able to hit them.

Thanks!

 

[HollowHill]

Have you heard when your stove is coming definitely yet?

 

[Waulie]

Have you heard when your stove is coming definitely yet?

Not a peep. You?

 

[HollowHill]

Called last week and said it would be this week, but have heard nothing since. Good luck with the hearth!

 

[rwhite]

Here is how I did it. I was face with the same issue and the wife wasn't convinced I should be cutting into the floor. This is a free floating extension but weighs 100 or more lbs and the front of the insert sits on it. It's nt going anywhere.

https://www.hearth.com/econtent/index.php/forums/viewthread/83582/