Fire bricks for heat storage

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New Member
Oct 4, 2021
Glasgow, Scotland
I see. The point of spacebus was that it is more efficient to move cold dense air to the stove than warm air from the stove.

Not to belabor my point, but the stone will be hot too (dogs). Moreover, water has a volumetric heat capacity of 4.18 J/cm3 K whereas soap stone has about 3 J/cm3 K. This means that moving the same volume of water )and at the same temp) upstairs gets you about 40% more heat upstairs. AND by only carrying 1/3 of the weight.

So, carrying 1/3 of the mass gives you 40 % more heat. And you'll likely have to pay for soap stone when water is comparably cheap (almost free for the quantity you would be using).

You're free to do as you wish, but I wanted to make clear that at the same temperature (and same danger level), the physics dictates that the most efficient solution is not soap stone. Convenience is of course an aspect that is hard to quantify.
Understand though I can put stones on top of my radiator where I can’t with a bucket. I’ll have a think and see what I could do.
Thanks for all your help and patience.
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Minister of Fire
Nov 17, 2019
Long Island NY
One remark; I assume "radiator" is in your upstairs room (and not a misnomer of the stove).

Be careful with that too; soap stone is heavy and slippery. I know radiators from "the continent" across from the small pond East of you, that are rather narrow. Falling heavy stones are (also) dangerous. If your dog puts his paws on there (e.g. to look out of a window ), this may be an issue. Maybe you have wider enclosures that mitigates that hazard.

In any case, let us know what you do (e.g. with some pics), and how it works out. I'm curious to learn whether this will work, as it is another avenue (from airflow/convection) to get the heat to spread. Good luck!


Minister of Fire
Can you up your insulation? That's one of the most cost effective things to do.