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Smoke Chamber Parging

A very small portion of the chimney system is accessible without the help of special equipment or cameras. One of the difficult to see – yet extremely important – components of the chimney is the smoke chamber.

What is a smoke chamber? Smoke chamber parging image - Seattle WA - Pristine Sweeps

Located directly above the firebox, the smoke chamber is designed to help the fireplace draft correctly. Smoke, gas, hot air, and other byproducts of combustion flow up and into the smoke chamber before they are funneled up the flue and out of the chimney.

Most older homes with masonry fireplaces have smoke chambers that were built with a technique known as corbelling. This building technique uses stacked bricks to create jagged steps as the smoke chambers narrows up to the flue; while this quick and easy building technique is effective, it has several design flaws that make it unsuitable for long-term use.

Smoke chamber repair and parging

The jagged steps of a corbelled smoke chamber have a number of exposed masonry joints and create plenty of nooks and crannies for the accumulation of soot, ash, and creosote. If your smoke chamber was constructed using the corbelling technique, the jagged masonry steps can be covered to create a smooth surface. Known as parging, this technique repairs smoke chambers by covering the jagged, staggered steps with a single, solid, smooth surface.

There are two main types of parging technique: cast in place and spray on. A cast in place restoration involves adhering the product directly to the corbelled masonry. Cast in place parging is also a good way to reinforce the structure of the smoke chamber. Spray on products are equally effective and can be easily sprayed onto the masonry in the smoke chamber to create a smooth surface.

Why parging is important

Because the smoke chamber is not seen, parging is not a cosmetic repair; it is important to the safety, drafting, and functioning of your fireplace system. The following are four reasons why having your smoke chamber parged is important.

  1.  Improved safety and efficiency when venting. With fewer cracks, edges, and corners, smoke and gas can easily flow up, through, and out of the smoke chamber.
  2. Reduce creosote and soot buildup. Creosote is extremely flammable, and excessive buildup of it in your smoke chamber and chimney can significantly increase your risk of accidental chimney fire. With fewer corners and joints there is a smaller surface area for creosote and other byproducts of combustion to accumulate.
  3. Reinforce masonry joints. The corbelled design of many smoke chambers has dozens of masonry joints; over time, smoke, gas, and heat can weaken these joints. Having the smoke chamber parged reinforces these joints and makes the smoke chamber structurally stronger.
  4. Extend the lifespan of the fireplace system. Having the smoke chamber parged meets modern building standards, makes the fireplace safer to use, and can help the entire chimney system last longer.

Parging your smoke chamber is a necessary repair. Having the smoke chamber parged can make your fireplace burn more efficiently – as well as significantly improve the safety of your fireplace system. For more information about smoke chamber parging or to schedule an inspection of your smoke chamber, contact Pristine Sweeps today!

By Aaron Woodward | Tagged with: Tags: , | Leave a Comment

Firebox Replacement

While it is built to withstand extreme temperatures and keep the rest of your home protected against the flames of a fire, the firebox may be one of the most delicate chimney components. If damaged, the firebox cannot effectively protect the surrounding building materials from the heat, smoke, flames, and gasses produced when the fireplace is in use; because of this, it is extremely important to have the firebox repaired or replaced if it becomes damaged.

What causes firebox damage?

Great Home Fire burning in the fireplace. Seasonal and holiday fire

Firebox Replacement – Seattle WA – Pristine Sweeps

Fireboxes can withstand prolonged, direct heat from flames – but this does not make them impervious to damage. The following are three of the most common causes of damage to fireboxes.

  • Water entry: Withstand heat and withstanding water are two different things; exposure to even small amounts of water can be dangerous to the refractory masonry of a firebox. Chimney leaks or attempting to use water to extinguish a fire can all cause water damage to a firebox.
  • Settling: All homes settle as they age; the footing that your fireplace was built on affects how well a fireplace will settle. Without a properly constructed base, the fireplace and chimney can shift and crack as a home settles. Large cracks in the firebox are commonly caused by settling due to improper fireplace footings. Outside, settling can also cause a chimney to shift or lilt.
  •  Incorrect construction: If a firebox is not built correctly using the right materials, it can quickly deteriorate and need to be replaced. Good fireboxes should always be built by masons – not contractors – using high quality refractory bricks and mortar. Cutting corners during construction may save money, but it can lead to fireplace performance problems and safety issues in the future.

Replacing a damaged firebox

If your firebox is damaged but the rest of your chimney system is in good condition, there is no reason to stop using your fireplace forever. Instead, firebox replacement can help you get the most out of your fireplace – without the cost of tearing down and rebuilding the entire chimney system.

Instead of taking out the damaged firebox and building a new one, a fireplace insert is often the best replacement. Inserts are easy to use and efficient heating appliances; available in a number of sizes and styles – as well as with several different fuel sources – there is the perfect insert for every family. Inserts can also be easily installed into an existing firebox, even if it is damaged. Because of the existing venting and chimney system, no additional construction may be necessary when professional installed.

Manufactured fireplaces can also be repaired or replaced. If the damage is localized to one part of the firebox, new refractory panels can be installed. Doing this can help extend the life of a manufactured fireplace when the rest of the unit is still functioning and burning safely.

If your firebox is damaged, your fireplace doesn’t have to be shut down for good. Instead, have your firebox replaced and go back to enjoying your fireplace again. For more information on firebox replacement, contact Pristine Sweeps today!

By Aaron Woodward | Tagged with: Tags: , , , | Leave a Comment