Rocket mass heater alternatives

Hey there,
I want to build a rocket mass heater fully with bricks only, I mean the entire system without the steel drum.
Cause I think that there will be much rapid heat loss from the steel one.
Would anyone direct me why not to do so? I'm not an expert but please, because I think it's gonna work fine and remain warm for longer hours.

Hi Keshab;
That is called a brick bell, it has become a very common design.
You are correct in that it will hold heat longer.
It also will take quite a bit longer to heat up.

The barrel's purpose is to provide instant radiant heat.  If your RMH is kept warm all winter long, then you will not miss that radiant heat.
However, during spring and fall, you might wish you had some radiant heat rather than waiting several hours for your brickwork to warm up.
After it has warmed up, you may find it is now way too hot indoors.

You can build a brick bell and then place a steel plate above the riser.
This will give you quick radiant heat and a spot to set a kettle but will have much less surface area than a barrel.
An RMH is not burned like a conventional wood stove.
In an insulated home, you do not need or want your RMH burning non-stop.
A fire in the morning and another in the evening is the only time your stove is lit, the rest of the time it sits there releasing all the heat you just added.

Thanks for responding almost instantly. Now I'm sure what to do without any doubt.

Yes the plate idea was on my mind but is thickness of the plate an issue or any thickness will do.

Thank you so much.

The very best choice is cast iron.   A thicker cast iron griddle would do the job.
My next choice would be a carbon steel plate,  I would use 1/4" thick and expect it to warp or spall at some point in the future.
By using a clay sand mortar it would be easily replaced.

Much appreciated for your kind support.

Thanks and regards. See ya