What is stove or connector pipe?

Stove pipe, technically called connector pipe, connects your stove to a chimney or vent system to send exhaust gases out of your house. It's typically made of a single layer of heavy-gauge, cold-rolled steel, and it is often known as black pipe. It is a crucial component of a wood stove—meaning you have to have it. Sometimes double-walled black pipe is used in place of single-wall black pipe to enable closer clearances to combustibles, and although it is a double-walled pipe, it is still considered stove pipe or connector pipe.

Stove pipes are not the same thing as chimney pipes although you frequently hear them discussed together. Stove pipes are for interior use only and are smaller in outside diameter than chimney pipes, which are typically installed outdoors. Chimney pipes are made of a double- or triple-layer metal and provide insulation to keep heat from escaping.

Is stove pipe necessary to run my fireplace?

It depends. All solid fuel fireplaces (wood, pellet, coal) must be vented to the outside, which requires pipe. Direct-vent gas fireplaces or gas log sets also need piping to vent the carbon monoxide. 

Electric fireplaces and vent-free gas fireplaces or gas log sets do not need piping.

How hot do wood stoves get?

Temperatures for wood stoves have many variables such as the type of wood you’re burning, solid fuel moisture content, and the amount of airflow to your fire. For peak efficiency and to keep creosote from building up in your chimney, the ideal temperature range is between 400°F and 600°F. 

Burning too hot can damage your stove, and burning too cool can cause creosote to build up in your chimney. Don’t guess on your temperature; use a stovepipe thermometer to be sure you’re in range. 

What chimney brands are compatible with my wood stove?

This is not a simple answer. There are many variables involved in the chimney you need for your wood-burning stoves and fireplaces, and it’s best to talk it over with an expert before buying your chimney material. We are happy to help you find what you need, call us at 888-418-005.

What is all-fuel chimney pipe and do I have to get a certain kind?

All-fuel chimney pipe is (as the name implies) designed to be used with all fire fuel types: wood, gas, pellets, or biofuels. Many companies manufacture all-fuel chimney pipe, which is also known as Class A chimney pipe. Class A is an insulated chimney pipe that comes in a variety of diameters to match the specific heating source or appliance. Some all-fuel chimneys are made of stainless steel and feature twist-lock couplings for quick installation. 

Often the term Class A is used in reference to insulated double walled chimney systems such as Metal Fab Temp Guard, DuraVent DuraTech, Duravent DuraPlus, Selkirk Ultra Temp, and Selkirk SuperPro pipe. 

Can I use a duct pipe for my wood stove?

No, duct pipe is not built to handle the intense heat produced by a wood stove, which can lead to damage and potential fire hazards. Duct pipe is often galvanized steel which will create dangerous off gases when under intense heat. Chimney and some connector pipes are made with multiple wall layers for better insulation, while duct pipes are typically single-wall. Plus, using the wrong pipe for your wood stove may violate local building codes. 

What is the difference between double-wall and single-wall stove pipe?

If you have only 6 to 18 inches of clearance between your wall and your stove, you need to use a double-wall pipe because it is air insulated. The outside of double-wall pipe does not radiate heat like single-wall pipe and is always recommended for use in a mobile home. 

Double-wall pipe typically 

• Lasts longer and improves the performance of your fireplace because the flue will have a higher and more consistent temperature
• Costs more than single-wall pipe
• Produces less creosote
• Offers fewer size options    

If you have a clearance of 18" or more, you can choose either single-wall or double-wall. Single-wall pipe typically

• Is less costly than double-wall pipe
• Radiates heat back into your room 
• Comes in a variety of sizes

What kind of stove pipe do you use outside?

A wood stove needs a stovepipe, also called a chimney connector or black pipe, to connect the stove to the outside of the building:

A stovepipe is used to connect the stove to a masonry chimney or prefabricated metal chimney. Insulated chimney is the only pipe that can pass through combustibles and can be used outside. The stovepipe is sometimes referred to as a connector. Single wall, 24-gauge or thicker, corrosion-resistant steel stovepipe is recommended. If the stovepipe diameter is over 10 inches, a heavier gauge metal must be used.

Most stoves do not include vent pipe. It will need to be purchased separately.

How high does a wood stove pipe need to be above the roof?

The chimney should extend at least 3 feet above the highest point where it passes through the roof surface. It should also be at least 2 feet higher than any part of the building within a horizontal distance of 10 feet. 

To calculate your necessary chimney height, please read our article The 10-Foot, 2-Foot, 3-Foot Rule. 

How do you clean chimney pipe?

A clean chimney is vital to the efficiency and safety of your wood-burning fireplace or stove. It’s a big job that requires time, knowledge, and special equipment. We recommend hiring a professional chimney sweep in your area; however, there are products and tutorials available for doing the job yourself. Call us at 888-418-0005 or email info@woodstovepro.com to discuss which option is best for your situation.

While there is never a good time for a house fire, the holidays seem like the worst time. You have plans for get-togethers. You have the house beautifully decorated. You have all those wrapped presents under the Christmas tree. You are prepared for a magical time - not a house fire.

Protect your home and your loved ones during this festive season with these tips for using your wood burning fireplace or wood stove.

• Clean your chimney. Be sure your chimney is inspected and clean. Smoke can cause creosote buildup, which can ignite easily. This is a messy and sometimes dangerous job so hire a certified professional
• Clear the area. Keep flammable things like curtains, furniture, and decorations away from the fireplace. Wrapping paper piled near a wood or gas heater can quickly become a fire hazard.
• Choose the right wood. Only burn dry, well-seasoned hardwood to minimize creosote buildup and smoke; avoid green or treated wood.
• Open the damper. Always open the damper fully before lighting your fire. You don't want to reach inside your chimney after someone lights the fire. That's a recipe for a smokey holiday and possibly worse.
• Install a spark arrestor chimney cap. A chimney cap with a spark arrestor helps prevent sparks from escaping and igniting whatever is close by.
• Use a fireplace screen. A fireplace screen helps catch embers and keep sparks from flying into your room. This could save your tree, your presents, and your carpet from an ugly demise.
• Test smoke alarms. Make sure to install smoke detectors near your fireplace and check that they work.
• Stay with your fire. Do not leave a fire burning in the fireplace without supervision. Be sure that supervisor is an adult.

Burning wood in your fireplace or fireplace insert adds a cozy element to the holidays. Imagine you and your family unwrapping your gifts beside its warmth and glow. By following the above safety tips, you can be sure that your holiday season is truly a happy one.

Still looking for the perfect wood burning fireplace for your home? Call our certified hearth professional at 888-418-0005 or email info@woodstovepro.com.

Written by: Sean Summers, National Fireplace Institute (NFI) Master Hearth Certified Technician - WoodStovePro.com

Stainless steel is a general term for a group of corrosion resistant steels containing a minimum of 10.5 percent of chromium. Varying additions of nickel, molybdenum, titanium, niobium and other elements may be present. The mechanical properties and behavior in service of the various types of steel depend upon their composition, and careful selection of the most appropriate steel grade is vital to success in any application.1

There are a few types of stainless steel, but for our purposes we’ll only focus on ferritic and austenitic (Figure 1). Ferritic stainless steels are plain chromium stainless steels, usually with low carbon content. They are magnetic and have good ductility and resistance to corrosion and oxidation. They are generally resistant to stress corrosion cracking.2 Ferritic stainless steel shares some traits with austenitic stainless steel but contains no nickel; therefore, they are less expensive to manufacture. This allows for a lower price point chimney pipe.

Austenitic stainless steels are those containing chromium and nickel with very low carbon content. They are non-magnetic, but can become slightly magnetic when cold worked. Cold working also enhances their strength. Austenitic stainless steels have excellent corrosion resistance; good formability; good weldability, and excellent mechanical properties over a wide range of temperatures.2 The addition of nickel increases corrosion resistance but also adds to the cost of the material.

Figure 2 demonstrates how austenitic stainless steels, 304 and 316, match up against ferritic stainless steels.3We can see that 304 has better corrosion resistance than 430, but 316 is an even better choice for use with corrosive materials.

Stainless steel grades 304L, 316L and 316Ti have altered compositions that have been developed to achieve different attributes. In the case of 304L and 316L, the carbon has been reduced. Carbon strengthens austenite so it is a useful alloying element in stainless steels used in applications like boiler tubes that operate at high temperature. Carbon has no other useful function and can be detrimental to corrosion resistance under certain circumstances.4 316Ti is a titanium stabilized version of 316 used where good resistance to intergranular corrosion and high temperature strength is required.5 So 316Ti is sometimes used in components that require elevated temperature strength and corrosion resistance such as flexible chimney liners.

When deciding which chimney to purchase, it is important to consider what fuel you will be burning and your budget. In most applications, 430 will do an excellent job and is cost effective. In situations where coal is the fuel of choice, a higher grade stainless steel would be a better choice. Below is a chart of various manufacturers’ chimney compositions. Woodstovepro.com carries M&G Duravent DuraTech and DuraPlus, Metal Fab TempGuard, Security Chimney Secure Temp and Selkirk UltraTemp, GalvaTemp and SuperPro.

If you have any questions, please leave a comment or send us an email. We are always happy to help.

*E-prosites has made every effort to ensure the information presented is technically correct. However E-prosites does not represent or warrant the accuracy of the information contained in this blog. This blog is for information purposes only. E-prosites, its officers and employees, disclaim any and all liability or responsibility of any kind for loss, damage or injury resulting from the use of the information contained in this publication. Please consult with pipe manufacturer for all technical specifications and advice.

1 British Stainless Steel Association - SSAS Information Sheet No.1.1 – March 2001
2 The Southern Africa Stainless Steel Development Association (SASSDA) website
3 International Stainless Steel Forum (ISSF) – The Ferritic Solution: Properties, Advantages, Applications – 2007
4 International Molybdenum Association (IMOA) – Practical Guidelines for the Fabrication of High Performance Austenitic Stainless Steels - 2010
5 Australian Stainless Steel Development Association (ASSDA) website

Written by Sean Summers, National Fireplace Institute (NFI) Master Hearth Certified Technician - WoodStovePro.com

Roof pitch is simply a numerical expression of the steepness of a roof. In the U.S., this is usually represented by a fraction in which the numerator signifies the rise and the denominator the run. For example, if we have a roof that rises 4 inches over 12 inches of run, then we would denote it as a 4/12 pitch. Pitch can also be expressed in degrees and discussed as an angle (see Figure 1).

The calculation of pitch is fairly simple. If you have two tape measures, or rulers, you can find the pitch from the rooftop or inside your attic space. Refer to Figure 2 to see how to arrange your tools for measuring pitch.

Please remember to be cautious when working on your roof or unfinished attic space. If you still have questions, please leave a comment or send us an email. We are always happy to help.

How to Determine the Chimney Height Above the Roofline

Questions about this rule come up a lot, and there seems to be a lot of confusion about it. Thankfully, this standard is actually quite simple. In most cases, with just two pieces of information, you can calculate the height of your chimney on paper without ever having to climb on the roof.

First, you’ll need to know the pitch of your roof.

Roof pitch is easily calculated, and if you don’t know how, read my article Understanding and Calculating Roof Pitch. Also, you’ll need the horizontal distance between the peak and the edge of the high side of the pipe (see Figure 1) where you plan your roof penetration. We’ll go over the math a little further down; first let’s go over the 10 and 2 rule (see Figure 2).

Chimney height requirements

Most wood stove and factory-built fireplace manufacturers (and local building codes) will require that “the chimney must extend at least 2 feet above any portion of any structure within 10 feet (measured horizontally) and must extend at least 3 feet above the highest point of its roof penetration.”**

Keep in mind there is generally a minimum chimney height requirement for the overall system (usually 15 feet, which sometimes includes connector pipe) that can affect the finished height of your chimney system. Other factors can influence the necessary height of the chimney such as “house stack effect” and high altitude. “Chimney height may need to be increased by 2-3% per 1000 feet of elevation.”** Although added height generally equates to stronger draft, there is a point where the system can become too long and over-drafting might occur, causing increased fuel consumption, hotter burn temperatures, and damage to your appliance.

Now for the math lesson

Roof pitch is expressed as a ratio of rise over run. Rise is the length, expressed in inches, that the roofline travels upward over a 12-inch horizontal distance, which is known as the run. For example, a common pitch like 4/12 would mean that for every 12 inches of run, the roof rises 4 inches. So, if the 10-foot, 2-foot rule requires us to measure 10 feet to the nearest roofline, or structure, then we can use the rise to calculate a height requirement. Back to our example, over a run of 10 feet, the roof would rise 40 inches. Additionally, per our rule, we need to add 2 feet, or 24 inches, giving us a total height of 64 inches. So, take the top number of your roof pitch and multiply it by 10 then add 24, note Example 1. If your calculated required height falls below 36 inches (3 feet), then, as per our rule, it must be a minimum of 3 feet on the high side of the pipe penetration.

This calculation from Example 1 alone would give you a solid working height, but if you are close to your peak then you might have more pipe height than you actually need. If you can measure the horizontal distance between the peak and the edge of the high side of the pipe where you plan your roof penetration, you can use that to calculate your height in relation to your roof peak or ridgeline. Often you can measure this from inside the room where you are planning to install the stove or inside the attic space. Many people mistakenly think that the pipe always has to be 2 feet above the roof peak.

Let’s look at a couple of examples.

You are close to your eave and you find that your measurement is 18 feet from peak to penetration on a 4/12 pitch (see Figure 3). For 18 feet of run, you would have a rise of 72 inches. If the previous calculation results in the required height of 64 inches, we can see that the top of the pipe will not rise above the roof peak but would still meet the requirements of the rule. For the next example, you have a shorter chimney height. If your peak to penetration distance is 7 feet, you would have a rise of 28 inches. Per the 10 and 2 rule, once you are at the level of the peak, you only need to be 2 feet above it. So 28 inches plus 24 inches is a chimney height of only 52 inches. This reduces the actual required height by 12 inches from our previous calculation of 64 inches.

Please note that this rule doesn’t generally apply to pellet and gas vent systems. Hopefully this article helped you understand the 10 and 2 rule but if you still have questions, leave a comment or send us an email. We are always happy to help.

Written by Sean Summers, National Fireplace Institue (NFI) Master Hearth Technician - WoodstovePro.com

*This post is meant to be a guide so always consult your appliance owner’s manual and local code before planning your system.

**Woodburning Hearth System Reference Manual. Hearth Education Foundation. Dec. 2002 pg. 92

There are many reasons people decide to purchase a wood stove. Everything from saving money to the nostalgia of growing up with a stove can play a role in the decision-making process. More often than not, many consumers are under informed when they begin their search for a wood stove. I hope this article will serve as a guide to help you plan and select the perfect wood stove.

Wood Stove Construction

There are two basic types of wood stoves on the market today: a steel wood stove and a cast iron wood stove. A steel wood stove is built from different gauges of steel that are welded together to create a wood stove.This type of construction is very durable provided that the firebox is designed to withstand long hours of heat and the steel is heavy and of good quality. A cast iron wood stove is made by individually casting parts and then assembling them with gaskets. A cast iron wood stove will eventually need rebuilt when the gaskets wear out, but they often make up for this failing by being more attractive than the average steel wood stove. One exception is the Napoleon cast iron wood stoves (1100C, 1400C), which are really steel wood stoves with cast iron parts bolted to the outside making them appear to be cast iron wood stoves. It has the beauty of cast iron without the drawback of being sealed with gaskets.

EPA Certification is Important

During the 1980s, the EPA began regulating wood stoves in an effort to reduce pollution and improve air quality. These regulations forced many manufacturers to invent ways to burn wood more efficiently. The first wood stoves after the regulations went into effect were built with catalytic combustors that allowed the unburned smoke to combust at lower temperatures inside the wood stove.Catalytic combustors are problematic because efficiency steadily drops over their not-so-long life span and the combustors need to be replaced.

Wood stoves are still being built today with this technology. The next generation of wood stoves injected super-heated air into the unburned smoke allowing it to combust at higher temperatures. The technology allows wood stoves to maintain efficiency over their lifetime without regular part replacement. Some manufacturers, however, kept their wood stoves rated under different categories, such as coal to avoid EPA certification. An educated consumer should be careful to choose EPA-rated wood stoves because the long-term cost savings on fuel can be significant.

How Big Should Your Wood Stove Be?

As an experienced hearth professional, I can’t stress enough the importance of sizing your wood stove properly. Too small and your space is chilly in the dead of winter; too big and you’ll have to open the windows to keep from sweating. The wood stove’s physical size is important but should never be determined by the size of the wood you already have cut and ready to use. Understandably, having a wood stove that can burn those 24-inch logs you cut would be nice, but the drawbacks of having a stove that is too big can’t be understated.

The newer generations of wood stove will use considerably less fuel and produce much more heat than older wood stoves. The British Thermal Unit, or BTU, is the crucial factor in determining the correct wood stove for your situation. Most manufacturers rate their stoves in both BTU and square footage, but be aware that the square footage number is all but useless. The manufacturer can’t know your climate, windows or insulation, which allows them to judge how many square feet a wood stove can heat. This is why you will see a wide swing such as 500 to 2,500 square feet on brochures (a rather large variance!). BTU should always be used to determine the proper sizing of a wood stove. A BTU calculator is very useful to find the correct size for your situation. Log size and burn times are also factors to consider but only after you have determined the proper BTU.

Class A Solid Fuel Chimney

Once you've determined the size of your wood stove or insert, you’ll need to make sure you have a safe chimney for venting. Always be sure to have your existing chimney swept and inspected before it is put into service, even if you are going to be relining it. Due to the efficiency of modern wood stoves, old masonry fireplaces require that you line the chimney with the same size pipe as the collar on the wood stove insert. Failure to do this correctly can cause improper drafting, chimney fires, and almost certainly a very dissatisfied user.

A freestanding wood stove will need a chimney connection so you’ll have to purchase and install a properly designed Class A solid fuel chimney system. An NFI Certified professional should be consulted to help you design a chimney system for your home. WoodstovePro offers this free service and has designed hundreds of systems. A new chimney system can cost 50 to 100% of the purchase price of the stove and should be factored into your budget.

Where to Put Your Wood Stove

Think of your wood stove as real estate: location, location, location. Putting your wood stove in the right spot can be the difference between a very warm and cozy home and a very dissatisfied consumer. Some houses will limit your choices and force you into finding creative ways of moving heat around your home. If you have the flexibility, place your wood stove in a central location. This will allow the heat to move easily thoughout your home. If a central location isn't possible, think about how you can move the heat to different areas of the home such as ceiling fans or using the blower of your forced air furnace.

If you are installing a new chimney system, keep in mind location so you can minimize chimney offsets and added expense. Also be certain there is enough room to meet the clearance-to-combustibles requirements. Each stove is different in design and requirements and sometimes this can change the placement of the wood stove. An NFI certified professional can help you with this process and be a valuable asset in helping you locate your new wood stove.

The Look

Don’t forget the aesthetic value of the wood stove you are considering.  It will become a focal point of a room so don’t underestimate the importance of how your wood stove looks. Your guests will be drawn to it. and you will find watching the slow dancing flames mesmerizing. This is a purchase you will have for many years, and you should find a wood stove that you enjoy looking at every day.

Other Considerations

Always check with your insurance company and local authorities before planning your wood stove installation. Some insurance companies are very averse to insuring wood burning appliances. You may have to go as far as switching insurance companies, so talk with them about your plans. Also, many local governments have strict rules on installation of wood stoves, so always check with them before you finalize your purchase.

Don’t forget that wood stoves burn wood. This may sound obvious, but make sure you have an available source of fuel. Good dry cord wood is the key to success. In our experience, the most common reason for customer dissatisfaction is that their wood has a high moisture content, meaning it isn't dry enough. This can cause major losses in efficiency and heat output. If you don’t have a place to store or purchase wood at a reasonable price, a wood stove may not be for you. Also, there is a fair amount of physical effort and time involved with using a wood stove - be sure you have the time and can handle the labor involved.

The last thing to consider is added expenses such as hearth pads, wall protection, installation costs, and yearly cleaning. Your NFI certified technician can help you identify everything you'll need during the search process.

WoodStovePro.com is not only NFI certified, but we are also Master Hearth Certified making us true professionals. We look forward to finding the perfect wood stove for your home.

Written by Sean Summers, National Fireplace Institute (NFI) Master Hearth Certified Technician - WoodStovePro.com