Buckley Rumford Fireplaces
Outside Air
Causes fireplace to smoke

From: "Geoff Metcalfe"
To: buckley@rumford.com
Subject: Smokey Fireplace
Date: Mon, 14 Feb 2005

Dear Jim,

I am sending this email per your request as a record of our experience with the smokey fireplace in a project we just completed in Schenectady, New York.

First of all let me say that I have thoroughly enjoyed speaking to you on multiple occasions reguarding this fireplace starting with the design of a true Rumford, and also diagnosing a problem with smoking once the project was completed. It is a joy to speak to someone who not only takes pride in his work, but is also so knowledgable on the subject in which he works.

We experienced a smoking problem with this particular fireplace where the fire would smoke at the conception of the fire during the time that the flue had not been warmed yet and didn't draft as strongly as when the fire reached its full potential. This lead us to the conclusion that there must be a negative pressure as discussed on you website.

After extensive testing with opening and closing doors and windows there seemed to be no change telling us that our first conclusion was incorrect.

The most unusual thing about the "draw" of the chimney was that it seemed to work fine approximately 18" above the hearth. Once the incense stick went below this line the smoke would simply float into the room and get blown around by the air coming in the fresh air intake.

The next step was to tape off the intake on the floor of the firebox which seemed to be making the hearth area about 15 degrees cooler than the air above it, thus not allowing the air to rise. Being that we are in a cold climate the air coming into this intake can be very cold. Well, taping off the intake did two things, first it cut the turbulance out completely, it also allowed the hearth area to warm up substantially almost immediately. After checking with an incense stick, then a small Georgia Fatwood fire (which smokes a fair amount) the problem with smoke in the living space completely disappeared.

In conclusion, we found that the fresh air intake on this particular fireplace was the cause of a fairly serious problem and could only be solved by sealing it all together. Unfortunately this is another case of Code requiring an item that isn't a good solution for all applications. With houses being built tighter all the time whole-house fresh air intakes are becoming more common and are truely a flexible, foolproof way to be sure you get the number of air exchanges necessary, and keep the pressurization of the envelope where it belongs. These systems really do make many other items such as fireplace intakes obsolete.

I have attached photos of said fireplace as well as the intake (on the exterior of the chimney) taped off for testing purposes.

Geoff Metcalfe
Keefe & Wesner Architects, P.C.
802-447-1724

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