Chimney Venting Requirements: Does My Chimney Need To Be Relined?

By Mengning Heil

February 4, 2022

Water Heater Tips

Reading Time: 3 minutes

If you own a home older than 30 years old, you may be required by state law to reline your chimney (check with your jurisdictional code authority regarding local chimney venting requirements).

Several decades ago, chimneys were crucial to how the home functioned. Appliances such as your furnace, fireplace, and water heater produced a large volume of heat and gasses that needed to escape up and out of the home through the chimney.  The amount of heat produced historically by these appliances heated the chimney structure long enough to allow adequate venting without the gasses cooling, liquifying, and settling in your chimney. 

Efficient Appliances and Chimney Venting Problems

In our present-day, appliances are designed much more efficiently. More efficient appliances produce less heat and gas. Although the energy savings is a wonderful advantage, the lack of heat and gas can leave you with chimney venting problems.  Simply put, a chimney that does not warm up enough will not vent properly. In other words, newer appliances can be so efficient that they do not actually produce enough hot air to push harmful gasses up and out of your home.

Efficient appliances may save you money but will not save you a headache if they leave gasses and residue in your chimney, or worse, in your house. This is especially true if the chimney is an exterior masonry chimney or if there is only one appliance using the flue. 

Efficient Appliances and Chimney Venting Problems

Chimney Venting Requirements: Masonry Chimneys and a Type B Vent Solution

However, if you have a masonry chimney, you do not need to worry.  In order to correct the venting issue in a masonry chimney, a licensed professional can correct the situation by installing a “Type B vent” (or “B Vent” for short) and liner.

A “B vent” is a double-walled metal pipe that attaches to your water heater and furnace. Then an aluminum or stainless steel liner connects the vent to the top of the chimney. The metal lining of a Type B vent requires less heat than a traditional chimney structure to transfer the combustion gasses out of your home and therefore leaves you with an efficient exhaust solution to match the new, more efficient furnace or water heater you may be needing to install. 

Chimney Venting Requirements - Masonry Chimneys and a Type B Vent Solution

WSSC Chimney Liner Code: Montgomery County, MD

For homeowners in Montgomery County, you are required by WSSC chimney liner code to get your masonry chimney relined. Back in 2015, WSSC began to require relining wherever a new furnace or water heater was installed with the vent going out of a masonry chimney. Therefore, if you need to have either appliance replaced soon, you’ll need to factor in this additional expense.  Although most of us are never thrilled by additional home improvement project costs, ignoring local chimney venting requirements could leave you with an efficient appliance that does your home more harm than good.

Are you looking for an expert plumber in Silver Spring, MD or the surrounding areas? Heil Plumbing offers a range of reliable plumbing services, including drain cleaning in Montgomery County and water heater repair in Rockville.

Heil Plumbing is a family-run company owned by a third-generation master plumber. We can help you with a full range of plumbing services, including toilet installation and repair, leak detection and pipe repair, faucet repair and installation, water heater repair, and drain cleaning in Montgomery County and the surrounding areas.