Single Wall Vs. Double Wall Stove Pipe: What Are The Differences?

Having a wood-burning stove can not only make for a great heating appliance but a nice aesthetic as well. It harkens to a simpler time and provides the kind of rustic look that more and more are looking to achieve.

But how do you know when you need a single wall or a double wall stove pipe? There are more than a few differences between the two but there the one main difference is clearance. A single wall stove pipe is for spaces with at least 18 inches clearance. A double wall stove pipe is for when you have less than that.

It is important to note one thing. A stove pipe cannot run into a combustible wall by itself. It is a potential fire hazard in this instance and should not be attempted by a DIYer. You should have a professional install it.

If you must perform the installation yourself, you have to have a Class A insulated pipe. This allows for a transition through the combustible wall and out of your home safely. These insulated pipes are used when there is no masonry chimney available or a closer clearance to any combustibles is needed.

You would use a single wall stove pipe for your stove or chimney into a ceiling transition box or a thimble. You never, under any circumstances, run it inside of a chimney chase or combustible wall.

For single wall stove pipes, you need a minimum of 18 inches clearance as well. Those pipes also have what is known as a fume-free finish so that you don’t smell the fumes from the stove in use.

A quality single wall stove pipe is usually constructed of cold, rolled steel. This is one of the thickest in the industry and should hold up over time. The smoother welded seams make for a much easier installation process.

You would want to use double wall stove pipes in the same manner as a single wall stove pipe. It should run into a thimble or ceiling transition box but the difference here is in the clearance distance. A double wall stove pipe is meant for clearances of less than the 18 inches required for a single wall stove pipe.

Like the single wall stove pipe, you would never run it directly through a combustible wall. The difference is also in the construction. Double wall means a cooler outside, which reduces the aforementioned wall clearance to a minimum of 6 inches.

Depending on the manufacturer, you may also find that they have a stainless steel liner to go with the steel outer pipe. That results in a much more durable design that is built to last over time.

There are two main benefits to going with a single wall stove pipe. Those are clearance and cost. Single wall stove pipes are a bit cheaper than their double wall counterparts. For those on a budget and the space to work with, it can be quite a big difference.

The other major difference is in clearance. If you have more space to work with, you can go for the more cost-effective single wall option. That is because they need 18 inches of clearance, which is more ideal for larger units.

If possible, you should always go with a double wall stove pipe for your installation. There are more than a few reasons for that. The first reason is that double wall stove pipes are substantially better in quality. Yes, they cost a bit more but they will last a lot longer than their counterparts.

Double wall stove pipes also have better insulation, which helps to keep the flue gasses warmer. When the gases are warmer, your stove does a much better job of resisting creosote buildup. When you have a buildup, creosote can smell nasty and it is highly flammable to boot, making it quite dangerous.

The lesser clearance is also another huge advantage of double wall stove pipes. Instead of needing a minimum of 18 inches, you need just 6 inches of clearance. That means keeping it much closer to the wall, saving your valuable floor space. For smaller homes that need to make the most of every inch, a double wall stove pipe can really help.

Finally, there is the transfer of heat. A single wall pipe radiates a bit more heat than the double, but the downsides more than outweigh that benefit. Simply put a double wall stove pipe is the safer of the two.

Just about everything seems to come down to cost. It is understandable that most are on a budget and only have a finite amount that they can spend on something like a stove pipe. That said, there are other factors at play that should make this an easy decision.

The double wall stove pipe is clearly the better option. It is the far more durable of the two. It is less prone to creosote buildup. Not to mention the fact that there is far less clearance required for the double wall stove pipe.

So long as you can justify the added costs, there is no question that the double wall stove pipe is the superior option. You can get by with a single wall, but you will be limited in so many ways. Find out how to install a wood stove pipe through a metal roof.

With a little more knowledge about the two, you are no doubt ready to make the right choice for you. But what about the litany of other potential questions that you may have? Think of this as something of an FAQ to single and double wall stove pipes.

Should you decide to perform the installation yourself, there are a few important things to know. Like what to do with the crimped portion of your stove pipe. You should always ensure that the crimped end goes down.

A lot of people seem to think that the crimped end goes up to keep the smoke in the pipe. That is definitely incorrect. Smoke not only goes up on its own, but it is also being drawn up into the chimney through a natural draft. Not only that, the crimped end goes down so if there is any creosote or condensation running down, it will stay in the pipe or the stove.

It is always ideal to screw the sections of stove pipe together. By doing so, you add a little extra measure of safety. Not only that, many building codes will require you to screw them together.

For double wall stove pipes, they can be screwed together so long as they do not penetrate the inner wall. You will need special stove pipe screws for that specific purpose.

You may decide that you want to get a double wall stove pipe but have a hard time justifying the costs. After all, budget can be the major deciding factor in just about any home installation or project.

So, when you look at the single wall stove pipe, you may be left with the question “are they safe?” The simple answer is “yes”, but there are some things worth considering. Make sure that you check the manufacturer requirements carefully.

Most wood stoves, for instance, need a larger draft in order to operate properly. In that instance, a single wall stove pipe would cause too much loss of draft. On top of that, you would eventually face creosote problems. A buildup of creosote can eventually lead to fire if you don’t clear it away.

Though you would probably better-served going entirely with one or the other, you can use single wall stove pipes with double wall stove pipes. Even better, you can usually do so without an adapter.

Double wall insulated stove pipes usually require an adapter, though. That adapter comes with a screw-on end that fits to the insulated part of the pipe. Ultimately, you would be better off using a single style of pipe. But in a pinch, you can get away with matching a single wall to a double wall as a temporary stopgap.