A bench deck is easy to construct, and will add comfort to any patio area. You can find plans for deck benches, or you can make your own. Here are the basics you need to know:
Step 1 - Make the Base
You will want to use 4X4's for the posts and the base of the bench. Construct these in a basic box form and attach them to the deck using a drill. If you are placing these against the railing you can also attach them to the railing for added security. You want to have one square constructed for every three feet of bench.
Step 2 - Seats
The seats can be made with 2X4's. You want to place them over the square bases 1/2 inch apart from one another. Countersink these in to the bases with a drill and deck screws.
Step 3 - Finish the Benches
Once you have the benches constructed, you can sand down the wood and paint or finish to your liking. It's easier to use an electric hand sander than just sanding by hand, but either method will work. Allow the stain to set before you use the bench.