Treated vs Pressure Treated Wood – Why All Treatments Are Not Created Equal

Pressure treated lumber and topically treated (often simply referred to as treated lumber), are popular choices for outdoor construction projects, but what is the difference between the two types of lumber treatment, and which one should you choose for your project? The answer to this question can be complex, but having the right information can help you understand the pros and cons of each type of treated wood. Be aware that not all Treated Lumber is Pressure Treated.

What’s The Difference? Pressure Treatment Goes Deep

Pressure treated lumber is often favored for its low cost, durability, and rot resistance. It’s created by forcing a preservative deep into the wood using pressure – a process known as pressure impregnation. The advantage of this method is that it offers extensive protection against decay and insect infestation, making it an ideal material for outdoor decking or fence installation. In contrast to pressure treated wood, topically treated lumber (or paint sealant) is applied to the exterior surfaces after sawing and drying needed components. While less expensive upfront than pressure treated lumber, topical treatment provides only surface-level protection against rot and pest infestations; any damage to the coating can lead to deterioration of the underlying wood. 

Lighter and Safer: Heat Treatment and Kiln Drying

Sunbelt Forest Products pressure treated fence pickets are also subjected to kiln-drying, topically treated lumber does not require this process, which can have certain advantages. Kiln-drying removes the moisture from the wood, allowing the pressure treatment to penetrate completely. The combination of kiln-drying and treatment makes the wood less susceptible to rot and pest infestations, as well as possible warping and splitting. In addition to offering protection against these issues, kiln-dried lumber is also lighter in weight than air-dried or green lumber, which makes it easier to handle and transport.

Choosing The Right Wood For Your Decks and Fences

Given their respective benefits and drawbacks, which type of wood is best for your project? If, for example, your specifications call for pressure treated pickets, topically treated pickets may not meet the requirements as a replacement. In fact, for decks or fences where maximum durability over time is desired, pressure treated lumber is likely the superior option due to its ability to resist moisture damage caused by harsh weather conditions. Those resistances will allow the wood to last longer and make it less likely that it will develop rot problems. However, for smaller projects like birdhouses or planter boxes where lasting strength isn’t a priority, topically treating a cheaper piece of raw lumber may be sufficient as long as you plan on maintaining it regularly with fresh finishes or stains. Overall, when selecting between pressure treated lumber and topically treated lumber there’s no single right answer — both materials have their place in outdoor construction projects based on cost considerations as well as project requirements. At the end of the day, it really comes down to weighing up all factors involved in order to make an educated decision about which material will give you maximum value over time while meeting the safety standards necessary for whatever project you’re working on.