Before installing any materials under the deck for removing moisture, you should perform some prep work on the ground. Work the dirt under the deck to create a grade away from the home. A grade of at least six inches for every 10 feet works well. Do not leave a gap between the dirt and the home’s foundation where water could pool. Once you or a contractor regrades the dirt under the deck, you then can add materials over the top.

In most cases, sanding an old deck before staining it is necessary to achieve a decent finish. If your old deck has a relatively new stain finish on it and you're only doing touch-ups, you can generally skip the sanding part. However, if your goal is to make the deck look and function better, sanding first is a must. 

Yes, Ipe wood is a popular high-end choice for pool decking. It repels water and is naturally slip-resistant. It's not susceptible to mold, mildew, or rot, either, so it lasts longer and is cleaner and more hygienic than other popular decking materials. However, remember that due to its status, it is a very high-cost wood, and you might find that an alternative would serve you just as well for significantly less.

When building an outdoor or deck gate, it's crucial to use durable wood that can withstand harsh weather conditions like sunlight, rain, wind, and snow. Redwood and cedar are excellent choices as they naturally resist decay. While redwood is considered more elegant, cedar is a more affordable option. Other suitable woods include oak and pressure-treated pine, which is specifically treated to resist rot. Although some softwoods like pine are popular, untreated softwoods such as pine and spruce should generally be avoided for outdoor projects because they are susceptible to damage from water, rot, and the sun. Ultimately, it's wise to consider your local climate when selecting the right wood for your gate.