I have an old deck. It is in need of a good cleaning and staining. One common mistake with pressure treated lumber is not sealing it or staining it. Just because the lumber has been treated to stand up to the elements does not mean it is 100% rot proof. Wood will rot. The rot process can be delayed by using the best material. It can also be delayed even longer by keeping that material clean and sealed. Mold and mildew can speed up the rot process on a deck. The mold and mildew will hold moisture directly against the deck and over time will break down the wood. If you have an older deck like I have, you need to thoroughly look the deck over for areas of concern. Look for boards that may need to be replaced. Look for areas with a lot of mold and mildew. Once these areas have been identified, take care of them. Replace the bad boards and treat the heavy mold and mildew areas with a good cleaner. Then clean the entire deck. Allow 24-48 hours for the deck to dry. During this time you can figure out if you want to seal the deck or clean the deck. It is up to you. You may want a shiny finish of a dull finish. After the deck is dry, apply the sealer or stain according to the manufactures directions. Give it another 24 hours to completely dry. During this time you can plan your next cook out and figure out which friends you are going to invite over. There are many how to videos out there to check out with a lot of good info. This is just a simple overview of why and how to clean you deck. If you are going to use a pressure washer, remember to keep the pressure low and use a gentle cleaner that is designed to be used with they type of decking material you have. If you have any questions or would like for us to come out and clean & seal your deck, please contact us.