Cost vs benefit of thermal mass design for hearth and wall protection

[michaelthomas]

I am going to be installing my englander 30 sometime soon and am wondering about the cost vs benefit of trying to design the install with some thermal mass in mind. Part of me thinks that I should just get the chimney in and put the stove on a prefab hearth pad and protect the wall behind it with micore and call it good. I would have the stove installed and it would be heating for me for under $2000. The other part of me thinks that I should carefully plan this out with long term benefits in mind. If I had some thick masonry installed behind and possibly on 1 side I would have some stored heat released into the room after the fire went out. But masonry is pretty pricey? Is it worth the cost for thermal mass? If the heat is stored into the brick will less of it be radiated out into the room at the time of the fire? Am I overthinking this whole thing?

Thanks

 

[cbrodsky]

This subject often comes up on here.

A few basic thoughts come to mind...

You need substantial mass - thousands of pounds - because it will not get much over 150-200 tops

If it gets anywhere near 150+, it needs to be isolated from wood framing with ventilated airspaces or other approved methods of protecting walls/floors - prolonged exposure to those temperatures will be a fire hazard

Stone/masonry is probably too expensive - but sand or other bulk material might be cost-effective, and could be encased in a more decorative stone/masonry/tile facade

Will need a lot of support for those thousands of pounds of mass

This mass can't be directly on an uninsulated basement slab or connected to an outside chimney or any other heat sink if it will be effective

This makes the problem quite a bit more challenging, but not impossible. For me, I have about 1000 lbs. of thick slate tiles surrounding my stove - previous calculations suggest to me that it's not doing a heck of a lot in terms of smoothing out heat load, but it looks nice

-Colin