Building RMH in existing basement

We are wanting to put a RMH in the basement of a regular stick built house that has a poured concrete floor and cinder block walls. If we build the RMH coupled to the floor and walls - won't we be heating the ground underneath? Thanks

I did the very thing, building in the basement, but I didn't couple the heater to the walls. The burn chamber floor is a layer of kiln bricks directly on the concrete floor, so the floor heats up pretty nicely, acting like a thermal battery. After the fire is out, even eight hours later the floor around the base of the heater is still warm.

I keep the heater running all day so the entire basement acts as my battery, then the stored heat just kind of emanates [convection] upwards through the night, keeping the second level around 65ºF even when it's well below freezing outside.

Hi, I know it's been many years since your post, Jeff, but I'm curious what size house you're heating, what size RMH you have, and which part of NH you're dealing with in terms of winter temps?