Heat shield behind wood stove - tiling advice

[ururk]

(I'm cross-posting this from forum.doityourself.com, just FYI, modified based on some responses I got over there)

## Intro

Back in 1999 we had an Encore catalytic stove installed. We had a 1" hearth pad put down, but no rear heat shield. The stove has rear, bottom, and front heat shields. The pipe exiting the stove is double-walled.

For the last 10/11 years, we've used metal shelves hung on the wall (temporarily, during the winter), but want to move away from this to a more pleasant solution.

I know the rear shield needs to be spaced 1" from the wall. I was planning on using ceramic spacers, but will probably use metal conduit. The other option would be metal hat channel (I'd prefer to use this).

## Questions

1) Is hat channel appropriate for this application, or should I use ceramic spacers?

2) What backerboard should I use, and how will I know if it will flex under the load with metal standoffs? Will I have the same problem with hat channel?

I've selected a product - a natural stone 'tile' - specifically, this stuff: http://www.tileshop.com/product/productdetail.aspx?familyID=359

It weighs 10.57 lbs/sq ft (based on the sample I got).

3) Should I double the backerboard?


## More info (diagram)

It will be covering an (approx) 4' x 8' area. Approx 338lbs of material (tile alone).

I posted a diagram (PDF) here:

http://ururk.com/house/wall-stove-schematic.pdf


The diagram shows (in brown) where the hardiboard will be placed. It might be difficult to see in the diagram, but the stove partially blocks a large (118" wide) "archway". We debated about adding additional drywall to the wall to extend it to the end of the hearth... but decided not to. The lighter shaded piece is wood moulding, and the large dark grey shape is the hearth.

Thanks!

John

 

[fossil]

Hello and welcome. Is a wall heat shield required in this installation because you reduced the stove's basic clearances to combustibles vis a vis the wall behind? Was the stove installed by professionals? What was said about the requirement for shielding behind the stove? Rick

 

[Chad S.]

I am doing the same thing and used metal studs for the spacers. the Studs are 1 1/4" wide when you put them sideways. I put durock on them with a lot of screws (3 1/2" screws through the studs, drywall then into the wood studs) And plan on putting ledgestone on it @12-16lb per sf. I have pics floating around here with the durock waiting for the ledgestone. I think it would be a nightmare using the spacers. If you go on durock's web site they actually have instructions on how to do it an suggest cutting the durock into 3" strips laminating 2 together for the spacers and putting the durock on that. Hope this helps.

 

[ururk]

I attached a photo of the space in case the diagram isn't clear.

 

[ururk]

Hello and welcome. Is a wall heat shield required in this installation because you reduced the stove's basic clearances to combustibles vis a vis the wall behind? Was the stove installed by professionals? What was said about the requirement for shielding behind the stove? Rick

It was installed by "professionals". It was a fireplace store, and the fireplace store installers installed it. When the house was originally built, a metal chimney had been installed - it was inspected by professionals, and we had to add additional chimney to meet current-day code (chimney opening was too close to roof).

From the specs, the stove is installed a safe distance from the wall. However, they suggested we put the rear shield in.

 

[fossil]

If the stove as installed meets or exceeds the manufacturer's required minimum clearances to combustibles, then no additional shielding is required. Some folks choose to add some sort of non-combustible decorative panel for additional peace of mind, but it just might be more trouble and expense than it's worth if there's no requirement for it being there. If you have the owner's manual for the stove, you can easily verify the clearances. If you don't have the manual, chances are good it's available somewhere online. Rick

 

[ururk]

If the stove as installed meets or exceeds the manufacturer's required minimum clearances to combustibles, then no additional shielding is required. Some folks choose to add some sort of non-combustible decorative panel for additional peace of mind, but it just might be more trouble and expense than it's worth if there's no requirement for it being there. If you have the owner's manual for the stove, you can easily verify the clearances. If you don't have the manual, chances are good it's available somewhere online. Rick

Hi Rick,

The stove, with rear heat shield, is 20" away from an unprotected wall. The manual says this number should be 19" - so it is 1" further than it needs to be ("luckily" the installed chimney was located in the right spot).

The trouble is, if I were to simply apply the stone directly to the wall, due to its thickness, the wall would then be 18" away, and not to spec - correct? The stone/backerboard would be touching the drywall, and conducting heat through it.

Additionally, the fireplace store recommended we install the heat shield on the wall when they installed the stove.

 

[ururk]

It just occurred to me that it might be helpful to know what I have installed:

1999 Vermont Castings Encore, Catalyctic

 

[fossil]

Personally, I don't think I'd bother doing anything with it. If you want to decorate the wall, I don't know why you couldn't just put the stone veneer right on the wall...you haven't changed the dimension from the stove to the nearest combustible material. If you're just dead set on building a vented shield, then I'd recommend just using doubled up strips of Durock behind the base sheet to create the 1" ventilated air space, and supporting the weight of the thing directly from the floor. Rick