Chimney Inspection

Jon LaBaron Chimney Check

Chimney Inspections have been around in Los Angeles for about 10 years. They are a specialized inspection that focuses solely on the Chimney. Due to the highly technical nature of Chimneys and the difficulty in inspecting them without the proper equipment (Telescoping Rods, lighting, and video camera), most General Home inspectors won’t be able to tell you much, if anything, about the condition of the chimney, and whether it is safe to use or not. 

I always recommend a chimney inspection if the property has a chimney (including condos). Chimney inspections are pretty common now, so expect your future buyer to have one when it is your turn to be the seller. Most people only use a chimney a few times a year during holidays, if at all. Sellers have caught on to this, and are not giving out big credits for $10,000 or $20,000 like they use to. You might see in listing remarks “fireplace is decorative only”. Sellers are excluding chimneys from credits and selling them as is. Even if you can’t get a credit for the chimney, it is good to know what is going on with it and to make sure it is safe if you want to use it. 

chimney-inspection

A Chimney inspector, will visually inspect the firebox, including the screens, gas connection (if present), the damper, and flue. They will elevate a camera through the flue chamber to check for cracks, gaps, or bad connections. Anywhere that heat can escape from the chimney into the walls is a potential fire hazard. The inspector will go on top of the roof and give a slight push to the chimney stack to see if it moves. They will also inspect the connection of the chimney at the roof line. This area needs to be properly flashed to prevent water intrusion into the house. They will inspect the chimney cap and spark arrestor, and evaluate the height of the chimney.  

Mike Rees the Chimney Guy inspecting a condo fireplace

Many single family homes in Los Angeles built between 1920-1940 have masonry brick chimneys that burn wood. These Chimneys have the most problems. They are coming up on 100 years old and almost always require maintenance and chimney repairs (the mortar that creates a fire barrier between the bricks and your house starts to turn to dust at around 100 years). 

 

1920s fireplace

1920s Masonry Chimney Diagram

Original Masonry Chimneys were constructed without flue linings which help support the weight of the chimney and prevent smoke escaping from grouting cracks within the stack.

Inside Chimney View

inside chimney

Masonry Brick Chimney with NO Flue Lining

chimney tile flue

Masonry Chimney with Clay Flue Liner

The chimney stacks on these chimneys are made of bricks, and are extremely heavy. This weight tends to make the chimney crack and shift or lean away and seperate from the house. A chimney that wobbles when light pressure is applied is a earthquake safety hazards- it could topple during a quake.

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This Chimney Wobbled when slight pressure was applied and needed to be replaced

As part of the clean Air act, beginning in 2009 the city of Los Angeles banned wood burning fireplaces from being built in new construction. Old wood burning fireplaces are grandfathered in, so if the property has one you don’t have to worry about losing it.

Technology has improved a lot since 1920s-30s. Chimneys are built smarter today. Back then, the chimney stack was made of all bricks. There are two problems with building a chimney like this:

1) The bricks are extremely heavy, which can make the chimney sag from its own weight or separate from the house over time
2) The heavy brick chimneys had no reinforcement and may be in danger of collapsing  during an earthquake

Chimney contractors nowadays build chimneys with a lightweight metal flue, and surround it in wood framing.

Metal Stack Modern CHimney

Metal Chimney Diagram

If you want the classic look of a brick chimney, worry not, you can have the chimney stack covered with brick veneers to give you that authentic brick look, without all the weight.

masonry chimney

This Chimney Stack was replaced by Parkstone Construction in a 1920s home Hancock Park. It has a metal Flue, and was covered with Brick Veneers. You can’t even tell the difference!

For a more affordable option, the chimney stack can just be stuccoed.

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Stucco Metal Chimney

The mortar that was used in Masonry Brick Chimneys in the 20s and 30s was a mix of lime and sand- Portland cement (also known as gypsum concrete) was added to mortar mix later for chimneys built in the 40s and 50s on and tends to weather far better. The old mortar in these chimneys turns to powder over time, and often requires a new parge coating to be sprayed within the firebox and/or a new liner, or heat shield installed to reinforce the brick chimney stack. Modern building practices no longer construct brick chimney stacks. Brick is fine for the firebox, but modern building techniques favor a much lighter prefabricated metal flue chimney stack contained within a framed chase covering. Home owners that desire a consistent brick look with a brick firebox can have brick veneers cut and stuccoed over the framed chase structure.

metal chimney

Inside framed chase of metal chimney

Gas fireplace systems like you find in condos tend to have much less problems and are less costly to fix. The main issues that come up with gas chimneys is improper installation. 

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