Recommendations for sheet metal heat shield & hearth for a Fisher Grandma

[MuskieMasta]

This is my first post on this forum, about my first wood stove in our first home.... So many firsts!!

I'm just looking for advice on reducing clearance to our drywall walls for installation. What I have been told so far:

• The sheet metal would need to extend 18" on either side of the stove and 20 " above the height of the stove.
• 1 " space between sheet and wall
• 1 - 3 " between the sheet and the combustible floor (guessing a non-combustible platform of brick or concrete needs to be built to achieve this)
• Minimum 29 gauge sheet metal

Any advice on this topic or even general wood stove advice and considerations are much appreciated. I always grew up with a wood stove but this is my first time ever having to install and actually operate one.

I apologize, as I'm sure I've missed some critical information that would aid in providing a response but hopefully I should be able to come up with it.

 

[coaly]

Welcome to the Forum;
Since this is a Canadian stove, I assume you are in New Brunswick Canada and not New Brunswick NJ?
Completely different codes.

If Canada, did this information come from a certified WETT inspector in your specific area? Do they require a manual?

Is the tag mounted on a rear shield? You then use the left side of tag "with" shield for clearances.

Your hinge pins are upside down! Are they peened over on the top to prevent them from falling out??? They should drop in from the top, be greased, and are removable by hand. Sometimes a tap with hammer and punch is needed to remove, but yours are defying gravity !

 

[MuskieMasta]

Thank you! Yes NB, Canada.

Info came from two different local wood stove suppliers although I can't be sure who I spoke with were actually inspectors. They did not ask about a manual and I don't actually have one for this particular stove. They phrased it as though it was a generalization for all wood stoves that clearance could be reduced by 66% by installing sheet metal 1 inch off the wall. They said cement board or tile would give a clearance reduction of only 50 %. They also mentioned that the heat shield values on the tag were only applicable for a heat shield installed on the back of the stove itself.

That's too funny about the hinge pins! I bought it that way and they supposedly had been using it for multiple seasons. Must just be the friction holding it in place. Will definitely fix them before the install though

 

[coaly]

Yes, the stoves were built with 1/4 inch steel plate and no shields for hearth installation in front of a fireplace or non-combustible wall such as masonry basement or solid brick. Shields were added for free standing in a room without sitting on a hearth in front of a fireplace. Below is a picture of a rear shield with tag; Most had a bottom shield as well with an opening across the front under ash fender for intake air. The air flow moves across the bottom, up the back and out keeping the floor directly under the stove much cooler.

If your tag is affixed directly to the back of stove body, it has no shield.

Here is a very good page giving you the basics of clearance reduction.
https://wett-inspection.com/clearances-for-combustibles/

Notice it gives details of heat shield construction such as where wall supports can go (none 8 inches from center line of stove) and how much vent space is required under and over it. The theory is to allow 1 to 3 inch air space below shield so hot rising air behind it has an intake of cool air at the bottom.

66% is the rule in the US as well, (for unlisted, which means untested stoves to UL testing criteria) but we start at 36 inches clearance, where you start at 48 inch clearance. So shielding reduces by 66% for us, or down to 12 inches minimum. You can't get any closer than the minimum. Brick in contact with wall gives us 33% reduction, or down to 24 inches from the original 36.

More installation guides;
https://wett-inspection.com/woodstove-installation-guides/

Gravity is your friend to keep the hinge pins and doors on your stove. I use silver anti-seize instead of high temp grease since it is higher temperature rated and seems to last much longer. Once a year keeps them moving easily.
(The older flat top door pictured above was not available with nickle plating, this is a custom nickel plated door and hinge pin)