| January 6, 2002
What's a Rumford Fireplace?
"Rumford fireplaces are tall and shallow to reflect more heat, and
they have streamlined throats to eliminate turbulence and carry away the
smoke with little loss of heated room air.
Rumford fireplaces were common from 1796, when Count Rumford first
wrote about them, until about 1850. Jefferson had them built at
Monticello, and Thoreau listed them among the modern conveniences that
everyone took for granted. There are still many original Rumford
fireplaces - often buried behind newer renovations-throughout the
country."
Below is a description of how a first-time amateur is building a
Rumford fireplace to comply with California seismic code. Since
Rumfords stack straight up, if you can lay a brick column, you can build a
Rumford.
When we're done, we'll publish plans to show optimal dimensions and
tips for the first time builder. |
Click to go to the Count Rumford Website:
www.rumford.com
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Rebar is epoxied into the house footings, and the
upright rebar is braced into position. Set the forms to the outside
dimension of the fireplace. Remember that the framing must be kept
2" away from the fireplace all around, and the gap will be covered
with flashing.
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| The concrete is poured to ground level. Since the
footing still needs to be built up to the level of the house slab, brick
will be laid around the edge, and filled with concrete. We did this
so only brick would show above ground. |
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| The firebox is laid up with Refractory Mortar (1 part
fireclay, 2 parts cement, 6 parts sand) and firebricks. The joints
are kept very small. Some masons even omit the joints on the floor,
just butting the firebricks up to one another. Small black thing in
the right-hand corner is the outside combustion air vent. |
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| Outside shell is built up with common brick. (Robinson Watertown
clay brick) and SpecMix type "S" mortar. |
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| The space between the shell and firebox is filled with
concrete. Notice the cheap brick on the inside face that will get
covered up. |
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| The 30" Rumford throat is set on top of the firebrick
with refractory mortar. |
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| A 3" angle steel lintel is set over the face of the
throat to support the brickwork above. The throat itself is strong
enough to support the brick, but code calls for the steel lintel, and it's
easier just to put it in than to argue with the inspector. Leave a
little bit of it showing for inspection after you laid the other brick
up. The stainless damper is sitting temporarily on top of the
throat. |
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| Felix stopped by just to see how things were going, and
quickly got drafted into learning all he ever wanted to know about
brickmasonry. |
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| Continue laying brick up to the top of the throat. The
brick with holes in it is called "kored", and the holes lock
together the bricks and makes them lighter. However, you end up
using more mortar. Solid bricks are used where the face shows. |
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| Fill the box up with concrete to the top of the throat. |
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