You should seal your deck every one to two years, but you’ll also need to clean and repair your wood deck throughout the seasons. You may want to hire a local house cleaning service to sweep and clean the deck thoroughly. These cleaning services cost around $50 per hour.

Inspect your deck at least once a year, and if you notice any damage or rot, expect to spend about $10 to $50 for simple DIY fixes or about $2,000 for professional repairs on more extensive damage.

Applying a sealer or topcoat after staining wood is highly recommended, though not always strictly required. A sealer protects the wood from moisture, UV rays, and weather-related issues, which is especially important for outdoor surfaces like decks and fences. It also enhances the stain's durability, prevents fading over time, and gives the wood a cleaner, more professional-looking finish. For some indoor applications, a sealer may not be necessary, depending on the type of stain used and the level of protection needed. It's always best to check the stain manufacturer's recommendations and consider the wood's intended use and exposure when deciding whether to apply a sealer.

The general consensus is that two coats of stain are required and since the cedar is siding, a third coat of sealant is always a good idea. This helps protect the wood and stain, so you won’t need to resand and restain for at least a decade. Each stain after the first will darken the wood, so be aware of that when choosing a colored stain.

Applying too much sealer to a deck might seem like extra protection, but it can cause more harm than good. Wood is a porous material with a limited capacity to absorb liquids. When you go overboard with sealer, the excess can't soak in and instead forms a film on the surface. This leftover layer is prone to peeling, cracking, and trapping moisture, ultimately defeating the purpose of sealing in the first place.