Overly Cautious? Hearth Meets Clearance Wall Questions

[TinasArk]

My non combustible (NC wall) metal stud frame for clearance wall, is currently set up and spaced out 2" with clearance on all four sides (top, bottom, left and right). We’re going to put up sheets of durock over that and seal the seams with fireproof (1200F) compound. The NC wall is 5 feet wide.

We plan on a hearth deck which is 4 feet wide. That leaves 6” of exposed NC wall on either side of the hearth to the ceiling. When we build our hearth deck (studs, plywood, Durock, and brick w/mortar) is it alright to have it meet the NC wall? Like actually join it with fireproof compound to make a seal, so no chance of any embers or sparks creep down under the hearth? That would leave the sides and top of the NC wall open for air circulation. My guy wants to put vents in the front of the elevated hearth he builds for air to pass under it and up the 2” NC wall space. Is this correct…sound right?

I’ve been on this site for 2 days now going through threads and pix trying to see that place where the hearth meets the NC wall, and haven’t had much luck.

Tina :/

 

[Backwoods Savage]

We plan on a hearth deck which is 4 feet wide. That leaves 6” of exposed NC wall on either side of the hearth to the ceiling. When we build our hearth deck (studs, plywood, Durock, and brick w/mortar) is it alright to have it meet the NC wall? Like actually join it with fireproof compound to make a seal, so no chance of any embers or sparks creep down under the hearth? That would leave the sides and top of the NC wall open for air circulation. My guy wants to put vents in the front of the elevated hearth he builds for air to pass under it and up the 2” NC wall space. Is this correct…sound right?
Tina :/

Tina, no worries there. Sounds like you have it figured out. It's sort of like where the hearth meets the combustible floor. The only part I don't understand is the need to put vents in the elevated hearth.

We also elevated out hearth (16") and the only thing I would do different would have been to put a small space for stacking wood under the hearth. Other than that, we love it. We built it large and it works great for drying boots and gloves.

 

[TinasArk]

Dennis,

So are you saying that you think it's okay to ease my guys concerns about straying embers, by using the joint compound to seal the place where the hearth and the NC wall meet? The joint compound will seal the 4 ft where the hearth and NC wall meet (even though the NC wall is 1 foot wider than the hearth)...which leaves 6 inches on either side of the hearth open for NC wall air circulation. That's why my guy is thinking that the elevated hearth with a vent in front will allow more the cold air to flow under and up the NC wall.

Thanks,
Tina

[quote author="Backwoods Savage" date="1226434686"][quote author="TinasArk" date="1226414937"]

Tina, no worries there. Sounds like you have it figured out. It's sort of like where the hearth meets the combustible floor. The only part I don't understand is the need to put vents in the elevated hearth.

 

[fossil]

Tte proper way to construct and install the rear wall is to provide for free airflow along the bottom. Typically, such a wall shield is intalled with its bottom edge 1" above the floor. If the wall were to be built of brick, then the joints between bricks in the bottommost course would be left free of mortar. The wall can be supported from the floor, but not continously across the bottom edge. The idea of venting the raised hearth isn't bad, it'll improve the performance of the hearth, I'd think. But I recommend against completely sealing the rear shield to the hearth...let it breathe. Rick

 

[TinasArk]

Thank you Rick,

Your advice/suggestions are always welcome.
My guy is breathing a lot easier after hearing these two replies.

Tina

 

[TinasArk]

Hi All!

A small update for all you kind people who took the time to help us out with our Vogelzang Boxwood BX26E (or insert your favorite “slam” term for this cheap little stove) woodstove install…

I wanted to let you know that we’re doing our first burn today. While it does have a smell like ironing a Polyester or Rayon shirt it’s tolerable. I have an exhaust fan in the window 4 feet away drawing the odor out, for the most part.

We’ve taken over 300 photos of building the entire set-up. I’ll post in the photo thread later.

Thank You All Once Again,
Tina