Building and designing a suitable frame is crucial for composite decking. Without it, a deck may structurally fail and can lead to many accidents. So for any homeowner and builder, a durable, long-lasting, and stable deck frame is a must.

The first thing you will have to decide when building a frame is selecting the appropriate materials. For many years, many preferred using wood over other materials. But with many varieties available, what is the best timber to use for decking? 

Best Deck Frame Timbers

Because of how crucial deck frames are, there are only a few suitable timbers for framing. In many places, including the UK, there are various building codes that you have to follow when dealing with this regard. If you wish to build a deck, it’s best to check your local building codes to ensure safety.

With that said, you have some choices when it comes to timber frames. But the question is, which is the best option for you? To determine the best frame timber, you will have to examine all of your options. Here are a few of them.

Softwood Timbers

Many prefer to use softwood timber for decks due to their low cost and availability. However, not all softwood timber varieties are suitable for decking frames. While there are some exceptions, softwoods tend to be less dense and more susceptible to many issues such as moisture and rotting.

A few examples of softwoods that you can use for deck framing is cedar and redwood. Despite being softwoods, cedar and redwood possess a natural resistance to moisture, rotting, and insects. They are also denser than many other softwood varieties. Within the softwood division, these two are among the most popular. They are even almost comparable to that of average hardwoods. There are several more others that are suitable for decking. 

Overall, softwood timbers such as cedar and redwood are excellent choices for decking frames. With their resistance to outdoor conditions, you can be sure that they can last for years. 

Pressure-Treated Wood

As previously mentioned, not all softwoods are suitable for decking frames. Most tend to be on the less dense side and are more susceptible to issues, such as moisture absorption, insect damage, and warping. With that said, they are not entirely unusable. However, before using them, they will need to undergo chemical treatment. 

timber for decking frame

Softwood timbers, often cheaper and lower-quality, must go chemical treatment to protect themselves from weather damage and other outdoor conditions. Treated Fir and Pine are some of the most common varieties of pressure-treated wood. The treating process involves removing all air in the timber and replacing them with chemical preservatives by injecting holes throughout the boards. 

Compared to untreated softwoods, pressure-treated are cheaper, as they use more common varieties of wood. They are also slightly better at resisting wood issues, such as moisture damage and insect infestation. Because of this, many have been using it for deck frames. 

However, there are a few downsides to them as well. For instance, the chemicals used for treating them are highly toxic to humans and animals. They can’t be disposed of or recycled the same way as untreated wood. Burning them will release toxic fumes, and the chemicals may wear off and cause irritation and damage when coming into skin contact. While resistant to many issues, one of the biggest concerns of pressure-treated wood is cracking and splintering due to the treatment process. 

Overall, pressure-treated timber is a cost-efficient choice for people who have some experience in building decks. But for people not used to handling them or prioritizing safety and sustainability, softwood framing may be better. 

Other Alternative Choices

Aside from softwood and pressure-treated timber, there are a few less common options that you can choose. While not preferred as commonly-used by others, these options are still suitable for deck framing. 

One alternative option is using hardwoods. Hardwoods are denser and more dimensionally stable than softwoods or pressure-treated lumber. They are also more weather-proof. The downside is that they cost significantly more. With that said, deck frames made out of hardwoods will last for a long time. 

Another option is using non-wood framing. Some of the most popular choices are vinyl and composites. Because they are plastic or part-plastic, they have better weather and moisture-proofing. 

Follow Your Local Codes

When choosing your deck frame materials, the most crucial thing to do is to check your local building codes. You will find detailed instructions on what bare minimum requirements for the materials that you can use. 

In general, pressure-treated timber is one of the best options for decking frames due to its cheap cost. Softwoods, such as Cedar and Redwood, are good choices for framing as well, especially if you want a more sustainable and safer option. Lastly, there are non-wood alternatives you can also consider, such as composites and vinyl.