1) If my chimney is broken is it still safe to use?
2) How often should I have my chimney cleaned?
3) What kind of wood should I burn?
4) What is creosote and how does it form?
5) How do you remove 3rd stage creosote?
6) Why do I need a chimney cap?
7) Whats the difference between a spark arrestor and a rain cap arrestor?
8) Does extending my chimney make it draw better?
9) How do I know if my chimney is tall enough?
10) How do I get rid of smoke stains on my hearth?
11) Which chimney is better to have fires in: Brick Chimney, Gas Insert or Pellet Stoves?
12) My house has a tile/metal roof, how do you walk on the roof without breaking/denting it?
13) How do I know how pitched my roof is?

1) If my chimney is broken is it still safe to use?

Answer: NO!!!!!!! If your chimney is broken, no matter where it is broken, it is extremely unsafe to use. Once the chimney is broken and another earthquake hits your chimney will fall! Your chimney will either fall on the ground, on yours or your neighbors car, or possibly through the roof of your home and into a room. A broken chimney is nothing to take lightly. You chimney from the roof up weighs at least 2,000 pounds and a 1/2 inch plywood roof and drywall ceiling will not stop it breaking through!!!! The safest thing you can do besides rebuilding it is to at the very least tear it down below the roof line so there is no chance of it crashing through your roof and seriously injuring someone. 

2) How often should I have my chimney cleaned?

Answer: You should have your chimney cleaned at least once a year if you burn a lot during the burning season. 

If you are a Duraflame user then twice a year because Duraflame dirties a chimney faster than regular wood. Duraflame is an amalgamation of wood chips, candle wax and kerosene which burns cool compared to hard woods and creates more soot. Duraflame soot is lighter and more fluffy than that of regular wood soot (almost like powdered sugar). Duraflame soot is also notorious for creating downdrafts and puffing into your living room on a windy day.
Note: Once Duraflame soot settles on carpet, furniture or any other fabric it will stain! 

3) What kind of wood should I burn?

Answer: Not all woods are created equal. Depending on what you want in terms of sustained heat or quick heat is based on the type of wood you use. There are two types of wood: Hardwoods and Softwoods. Hardwoods are better for sustained heat and burn more efficiently. Softwoods are better for igniting a fire very quickly but don't burn as efficiently. When building a fire you want to use softwoods to prime (heat up) the flue and then put on a split piece of hardwood to keep the fire going. 

Here's a list of some woods and their available heat (million BTU/Cord):

- Almond = 24 
- Live Oak = 24
- White Oak = 23
- Red Oak = 21
- Walnut = 20
- Eucalyptus = 20
- Douglas Fir = 19
- Cherry = 19
- Maple = 19
- Cedar = 14
- Pine = 12
- Redwood = 12
- Willow = 12

* 1 Million BTU equals: 293 kilowatt hours of electricity, 12.5 therms of natural gas or 13.6 gallons of propane. 

4) What is creosote and how does it form?

Answer: Creosote is a flammable tar like substance. Much like how glass is created by melting sand, creosote is formed the same way by glazing over many years of unburnt wood residue (soot). The smell of creosote is very subtle to those who have it in there house but others will notice. Creosote smells like a barbecue gone very wrong. Not only is creosote extremely flammable but also poses a very dangerous health risk. Prolonged periods of exposure to creosote can cause severe neurological disturbances. Some symptoms include severe headaches, breathing problems, nausea, flu like symptoms, etc. If you notice that you have these symptoms in your house but not anywhere else then you may have creosote in your chimney. Contact a licensed chimney professional to determine if you have creosote.  

                                                                                                                Before Flue Fire                                       After Flue Fire

Creosote, as you can see, begins as a hard sticky glaze like substance that is very flammable. Once it catches fire it expands to the 'honeycomb' like conclusion which is very brittle. Note: Just because the burnt up creosote remain can be brushed out easily does not mean there is no more safety concerns regarding your chimney. In fact many more may remain. Your flue tiles may be split in multiple areas, creosote can form in tile voids, 3rd stage creosote may still remain underneath and so on. Call a licensed chimney expert to assess the situation.

5) How do you remove 3rd stage creosote?

Answer: The only way to remove 3rd stage creosote is to chemically remove it with Sodium Hydroxide. Sodium Hydroxide is a powerful cleaning and neutralizing agent that penetrates and dries out thick baked on creosote. Applying Sodium Hydroxide is very dangerous because of its extremely corrosive properties. Eye, face, hand and arm protection must be used when handling as it begins to burn skin on contact. Once the Sodium Hydroxide is applied the front of the fireplace must be covered up in order to prevent unpleasant 'rotten egg like' fumes from coming into your house. Sodium Hydroxide needs about 5 days to do its job depending on the outside temperature. The colder the weather the slower the reaction time. After 5 days the creosote can be roto-chipped out leaving the flue tiles looking near brand new. There may be some traces here and there where the roto-chains can't reach. After each job we leave ACS (Anti Creosote Spray) in order for the customer to neutralize the remaining bits and pieces of creosote that may be lingering in small places. This will also help prevent further build up of creosote if properly used.

​Note TSR stripping 3rd stage creosote does not guarantee your chimney is safe to use. Once the creosote is out and the inner flue liners are re-inspected the flue liners may be cracked in multiple places and rebuilding the chimney is needed. 

6) Why do I need a chimney cap?

Answer: The reason why you need a chimney cap is to prevent water from entering your chimney and causing hundreds of dollars in water damage to your chimney. Also chimney caps prevent any sparks from escaping your chimney and possibly catching your roof or any other combustible in close proximity on fire. It also prevents critters from entering your chimney and calling it home. Such critters include birds, bees, squirrels, raccoons, bats....


7) What is the difference between a spark arrestor and a rain cap arrestor?

Answer: The difference between a spark arrestor and a rain cap arrestor is pretty simple as you can see in the following pictures:

A spark arrestor is just metal mesh screening that covers the opening of your chimney allowing water to enter easily. 

A rain cap arrestor is a spark arrestor with a lid that covers the opening of your chimney preventing any water from entering.

8) Does extending my chimney make it draw better? 

Answer: No, extending your chimney does NOT always make your chimney draw better. This is an old wives tale. Your chimney is built to certain specifications from the very beginning so you don't have to extend it. For example, which is easier to siphon gas from: a 5ft hose or a 20 ft hose? The taller you make your chimney the harder you make the smoke have to work in order to escape. Remember smoke is very lazy and will find its easiest way out. And if you extend your chimney the easiest way out for smoke is unfortunately inside your house.

Here are some example of what to look out for:


If anybody suggests and/or tries to sell you something to extend your chimney beyond the code requirements say no and save some money and your living room.

The only times extending a chimney is needed is when the chimney is below the pressure zone (below the nearest roof eave) and air is pushing down on the top of the chimney preventing the smoke from exiting. Or if there's a tree or some other obstruction nearby that is causing turbulence that affects the smokes ability to escape. 

9) How do I know if my chimney is tall enough?

Answer: How you figure out if your chimney is tall enough is very easy. Measure out 10 feet from the chimney out horizontally to the roof. Where ever that point is your chimney needs to be 2 feet above that point. Now if your chimney is closer than 10 feet as long as it is 2 feet about that it is the correct height. if the chimney is at the ridge of the roof then it needs to be 3 feet above that.  

10) How do I get rid of smoke stains on my hearth?

Answer: If you see smoke stains on your hearth don't panic there are ways to remove that ugly black mess and make your hearth pretty again. 

1) Soap, water and a rag/brillo pad. This is a more difficult way to remove smoke stains but it is the safest. 

2) Sodium Hydroxide cleaner. This is the easiest way to remove smoke stains but precautionary measures need to be taken when using this method. With any Sodium Hydroxide product whether it is stove cleaner or a product a service company sells you must at all times wear rubber gloves, long sleeved shirts, eye and face protection. Stove cleaners are not full strength versions of Sodium Hydroxide but it still can cause skin and eye irritation. Always practice safety when using these kinds of products. 

 11) Which chimney is better to have fires in: Brick Chimney, Gas Insert or Pellet Stoves?

Answer: There are different things to take into consideration when it comes to having fires in any of the above units: Heat Efficiency, Emissions Output, Costs to run the unit and Cost for fuel.

With heat efficiency there are some things to think about that will affect your units heat output: Where is the unit located in the house, Does the unit produce enough BTU's to heat your house, Condition of the wood, and Operator techniques. If all conditions are satisfactory then the efficiency of the units are as follows:

Masonry Fireplace = -10% to 10%
Freestanding Stoves = -10% to 30%
Fireplace Insert = 35% to 50%
Gas Insert = 60% to 80%
Pellet Stoves 75% to 90%

Emission outputs are as follows:

Masonry Fireplace = 60 grams/hour
EPA Rated Wood Stove = 6 grams/hour
Pellet Stoves = 0.5 grams/hour
Gas Inserts =  0.07 grams/hour

Cost to run each unit is:

Masonry Fireplace = 0 
Pellet Stoves = 27 watts/hour (Check PG&E rates)
Gas Stove = Check PG&E rates

Fuel costs: 

Masonry Fireplace = $250 - $500 a cord (4'X4'X8' stack) 
Pellet Stoves = 1 Ton (2,000lbs) pellets $279.00
Gas Inserts = 1ft3 of gas is 1,000 BTU's (Check Insert BTU output & PG&E rates)

 12) My house has a tile/metal roof, how do you walk on the roof without breaking/denting it?

Answer: Walking on tile and metal roofs can be very difficult if you don't know how to walk on them. We here at Mr. Chimney Builders & Dryer Vents R' Us know how to walk on all types of tile and metal roofs.

Here are pictures of how and how not to walk on certain types of roofs:


13) How do I know how pitched my roof is? 

Answer: For someone that is not familiar with roof pitches it can be difficult to figure out how angled your roof is.

As you can see from the image above its pretty simple to determine the pitch. First you measure out horizontally 12 inches (1ft) then you measure vertically and where the roof line intersects is how pitched the roof is. For example if you measure out 12 inches and the roof intersects at 6 inches up the pitch of your roof is 6/12.
Here are some examples of different roof pitches.

It is important to let a service person know if your roof is pitched because special equipment may be required in order to perform the job safely. Any roof above a 6/12 pitch may require special equipment to safely inspect your chimney.

Chimney FAQ's