Rumford Technical Discussion
How it Really Works in California
NOTE: This is not a strategy that we advocate. Rules and rule makers may be misguided but we advocate following them if they don't matter and appealing those that do matter based on reason, logic and science.
10/17/03
To: "No Name"
From: Jim Buckley

"No Name",

Thanks for the feedback. It's interesting to see how regulation actually works in the real world. I'm surprised that you had trouble with the 20". The code is pretty clear both in the 1997 UBC (still in effect in California) and the new International Residential Code. Here is the language:

    R1003.6 Firebox dimensions. The firebox of a concrete or masonry fireplace shall have a minimum depth of 20 inches (508 mm). The throat shall not be less than 8 inches (203 mm) above the fireplace opening. The throat opening shall not be less than 4 inches (102 mm) in depth. The cross-sectional area of the passageway above the firebox, including the throat, damper and smoke chamber, shall not be less than the cross- sectional area of the flue.

      Exception: Rumford fireplaces shall be permitted provided that the depth of the fireplace is at least 12 inches (305 mm) and at least one-third of the width of the fireplace opening, that the throat is at least 12 inches (305 mm) above the lintel and is at least 1/20 the cross-sectional area of the fireplace opening.

How did you spend the $1,000 and why didn't you let us try to reason with your building official?

Anyway, glad the fireplace works and that you seem pleased.

Warm regards,
Jim Buckley


Here in California, glass doors are required to get an occupancy permit for a new house. Our solution was to rent them - there are people here who do this! We fastened them in place with a few screws in the masonry joints of our surround, got our permit, and took them out. The screw holes were easily repaired. Another big problem here is the minimum firebox depth requirement of 20in. We spent about $1000 trying to get this waived by the local building inspector, but finally gave up and built the 20in. depth. In spite of this, our 2 fireplaces work just great.

There is surprisingly little smoke residue on the firebox walls, and we use castiron firebacks. Other than the depth, they are true Rumford designs, 36in. width and 34in. height. Our brick is "Rose Red", from Maryland, and the hearth is laid without mortar into the firebox floor.

"No Name"

and, subsequently...

I didn't mention that our house was being built in 1991-2 and that we did communicate with you at that time - you were just getting started, I think. I found the information that we got from you very helpful. I also was using Vrest Orton's book on Rumford fireplaces. The $1000 was spent on architect's fees in documenting the history of the design and making a presentation and appeal to the local building official*.

[Back to Technical Discussion]

Buckley Rumford Fireplaces
Copyright 1996 - 2010 Jim Buckley
All rights reserved.
webmaster