Chimney dynamics and building techniques have changed over the years as the industry has learned more and safety and efficiency. Because of this, some older homes have chimneys that were built using now outdated techniques. One of the best examples of this is smoke chambers; if built using a corbeled design, they need to be parged in order to vent safety.
What is a smoke chamber?
Smoke chambers are located directly above the firebox. While all smoke chambers are designed to help the fireplace draft by directing smoke and gas up the chimney, building techniques have changed over the years.
Many older homes have smoke chambers that were built using a technique called corbelling; this stacked step design makes it quick and easy to build a smoke chamber but is ultimately unsuitable for long term use. Because of this, the jagged steps in the smoke chamber need to be smoothed over through parging.
What is parging?
Parging is the process that is used to create a solid, smooth surface over the surface of a corbelled smoke chamber. There are two main parging techniques that are used to smooth over the jagged edges: spray on and cast in place.
Spray on parging is easy to apply as it is sprayed directly onto the corbelled surface by a chimney sweep. This smooths any masonry edges or corners and creates a solid, seamless surface. Cast in place restoration creates the same smooth surface with a slightly different technique; instead of being sprayed on, the product is adhered directly to the corbelled surface. Cast in place restoration is often used in instances when the structure of the smoke chamber needs to be reinforced.
Why parging is important
Parging is not just a cosmetic repair; it helps your fireplace last longer, draft more efficiently, and burn safely. Below are four reasons why parging your smoke chamber is important.
1. Improves safety and efficiency. A smooth surface allows smoke, gas, and other byproducts of combustion to better draft up your chimney.
2. Reduce buildup in the smoke chamber. The corners, nooks, and crannies created in a corbelled smoke chamber leave plenty of room for buildup of soot and creosote; a smooth, parged surface reduces the risk of buildup in the smoke chamber.
3. Reinforce masonry. As mentioned before, parging the smoke chamber with a cast in place restoration can help reinforce the masonry of the smoke chamber. This is important as years of exposure to heat, smoke, and gas can sometimes weaken masonry joints.
4. Extend the life of your chimney system. Parging makes sure your chimney system meets modern safety and efficiency standards; doing so can ensure your fireplace can keep burning for years to come.
Parging your smoke chamber is about more than cleanliness and efficiency; it is a necessary repair that makes your fireplace safer and greatly reduces the risk of chimney fire. To schedule an inspection of your smoke chamber or for more information on parging contact Coopertown Services today!