Chimney Services in Deptford, NJ

What the numbers suggest for chimneys in Deptford

Census estimates spread Deptford's 12,502 housing units across several eras: about 21% from 1940 to 1959, 28% from the 1960s and 1970s, 23% from 1980 to 1999 and 22% since 2000, with 5% older. A chimney is sized and placed for the roof it was built with, so on the older part of that range the original roofline set the chimney's height.

About 83% of occupied homes heat with utility gas, 10% with electricity, 4% with fuel oil and 0.9% with wood. Fireplaces, wood stoves and gas appliances that vent into a chimney all depend on draft, and draft depends partly on what surrounds the top of the chimney. Our guide on why a fireplace won't draw covers the other causes.

About 73% of units are detached houses and 13% are in buildings of five or more units. These are township-wide estimates and describe no single chimney.

The 2-foot, 10-foot rule and what an addition changes

The International Residential Code sets a minimum height for masonry chimneys: the top must clear its own roof penetration by 3 feet or more and stand at least 2 feet above anything on the building within 10 feet (section R1001.6 in the 2003 edition). Wood stove manuals repeat the same test. The Jøtul F 400 manual adds a 15-foot minimum overall chimney height for that stove.

The words "any portion of a building within 10 feet" are what catch additions. A chimney that met the rule on a one-story house can fall short once a second story or a taller wing goes up beside it, because the new roof is now the part within 10 feet.

Our guide to how tall a chimney should be explains the rule in more detail, including how it applies to factory-built chimneys.

Raising the chimney, or changing what it serves

• Extend the masonry. Brick and flue tile are added to the top, and a new crown is formed. That only works if the chimney below is sound enough to carry the extra height, which an inspection settles first. Our chimney rebuilding page covers the work.
• Brace the taller stack. Extra height adds wind load. Guidance from the U.S. Department of Energy's Building America Solution Center flags tall, slender brick or stone stacks as more vulnerable and calls for tying chimneys to the roof framing.
• Check gas appliance vents separately. A furnace or water heater vent follows the termination rules in its own installation instructions, which the heating contractor applies.
• Change the fireplace. If the fireplace sees little use, converting to a gas fireplace that vents through the wall, or retiring the fireplace, can make raising the chimney unnecessary.

The easiest time to solve this is during design, before framing starts. An inspection before the addition records the chimney's condition and the height it will need to reach, so the builder and the chimney work can be planned in sequence.

Local questions

Sources

1. U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates (tables B25034, B25040, B25024), via Census Reporter
2. 2003 International Residential Code, Chapter 10, Chimneys and Fireplaces (text reproduced by Buckley Rumford Fireplaces)
3. Jøtul F 400 Castine wood stove installation and operation manual (PDF)
4. Pacific Northwest National Laboratory, Building America Solution Center: Chimneys Connected to Roof Structure