Custom BBQ Smokers

Horizontal bbq smokers have become quite popular over the past 25 years or so. They are designed specifically for slow cooking at low temperatures. This assures that the meats will be enhanced with the smoke flavor and have a tenderness which cannot be attained by cooking with a high temperature directly over coals or with propane gas on a typical grill.

The key elements in a horizontal smoker involve the sizes and the positioning of the fire box, the fire box air inlet, the heat/smoke inlet into the cooking chamber, and the smoke exhaust outlet.

When we started building smokers back in the 1990's, we experimented with several designs which included some features which are still mistakenly being used by many of the bbq smoker fabricators of today. Features such as heat deflectors, manifolds, and tuning plates all came about as methods to try to control the flow of heat and smoke through the unit because the basic design of their horizontal smoker was flawed.

Many manufacturers still mount their fireboxes too high and use much too large of an opening into the cooking chamber. In many cases, these large openings extend above the level of the cooking racks. Many have their smoke exhaust stack located at or near the very top of the unit - so most of the heat and smoke travels up and across the top of the cooking chamber and then out the exhaust stack. Some manufacturers have their smoke outlets situated on the vertical end wall of the cooking chamber, but they are usually located between the upper and lower level of cooking racks. The result is that the entire area of the cooking chamber containing all of the cooking racks cannot properly fill with heat and smoke.

While tuning plates and manifolds allowed the upper portion of the cooking chamber to fill with smoke, they also have a flaw in that they can create hot spots beneath the cooking racks which can blister or overcook the bottom side of the meats. The same is true for the reverse flow type units. As a result, much of the cooking is done not with the heat and smoke which travels through the unit, but with the radiant heat which is being emitted vertically from either the manifold, or the tuning plates, or the reverse flow plate.

The overall result with all of those features is inefficiency - they cost more to build, they consume much more wood, and the bbq cook usually has to watch the meats much more closely, opening the unit often in order to turn the meats to keep them from getting blistered on the bottom side.

The problem with most of these features, which all came about as means to try to fix the basic design flaws, is that they are trying to fight some very basic laws of physics. We should all know that heat naturally "rises". Hot air balloons are a good example of this - the hot air inside the balloon is lighter (less dense) than the colder air (more dense) surrounding it - the colder and more dense air forces the hot air balloon upward. The same thing happens inside a horizontal smoker - the smoke and heat enters the cooking chamber and will "rise" because the cooler air in the bottom portion of the cooking chamber forces it upward until it contacts the top of the smoker - then it will naturally follow its' path of least resistance towards the opening of the smoke exhaust stack. If the exhaust opening is located at the top of the cooking chamber, then it is obvious that the path will simply be across the very top of the cooking chamber.

If the exhaust opening is located at or slightly below the level of the bottom cooking racks, the smoke and heat enters the cooking chamber and rises until it contacts the top of the cooking chamber - then as it seeks its' path of least resistance, it will move in a swirling motion across the entire length of the cooking chamber, filling the entire portion of the cooking chamber which is located above the opening of the exhaust stack before it flows out. With our basic design, the swirling smoke and heat comes into contact with all sides of the meats and results in a very even smoke ring in the finished meats. We cook briskets and Boston butt pork roasts with the fat side up and never have to turn them over. Less wood is used and there is much less work for the cook.

Another common mistake with horizontal smokers is in the sizing of the firebox. We discovered over the years that large fireboxes are not necessary and that for peak efficiency, they should not have a removable top or a side access door. Over time, such removable tops and side access doors can warp and create gaps which allow a lot of the heat and smoke to escape. You end up burning much more wood than is necessary.

Large fireboxes have much more surface area than smaller fireboxes, so they dissipate much more heat to the surrounding atmosphere than does a smaller firebox. (Heat which does not contribute to the actual cooking of the meat is simply wasted heat, which equals wasted wood.) After many trials and errors, we discovered that a firebox only needs to be 16 inches tall and 16 inches wide, with lengths ranging from 18 to 24 inches.

The result is a very efficient and easy to operate bbq smoker.