How to Renew Wooden Fences | Family Handymanfence stain. Make a gray, sagging wood fence look new again. With a few simple repairs, a thorough wash with a power washer, and a nourishing coat of oil stain your fence will look almost like it did the day it was built. By the DIY experts of The ... They'll strip the wood as well as clean off the dirt and grime, but you can also erode the wood too deeply and ruin it. .... before recoating, wash the fence with a garden hose sprayer and use a bristle brush on stubborn dirt deposits and stains.