Composite decking may never warp, or it may warp quickly. Several factors can influence the rate of warping, including the material's quality, installation method, and installation location. Generally speaking, high-quality materials that have been installed properly are drastically less prone to warping.

You can use a few different tactics to prevent your deck gate from sagging. Aside from using strong, rot-resistant woods, introducing a diagonal element—such as a tension rod or solid piece of wood to act as a brace—across the gate will offer better support. You can also use rigid joists to prevent the gate from sagging.

Finding a reputable deck builder should start with speaking with a local company and asking for samples of past work and references. You can review the company’s workmanship and speak with past customers to learn what the customer service was like throughout the process. It’s also a good idea to read online reviews and check the Better Business Bureau (BBB) website to see if the company has a history of customer complaints. If you can get a referral from a family member or friend, that’s another great option.

Pressure-treated decking may be worth it if you want a natural, insect- and rot-resistant decking material that will last for decades with proper maintenance. As such, it’s a much better option than untreated pine. Alternative wood decking materials like cedar and redwood tend to be less durable and more expensive. Some homeowners prefer composite decking, which is a low-maintenance alternative to wood but is also more costly.