How to Finish a Wood Railing

What You'll Need
Twine or heavy string
Sanding block
Sandpaper 80 grit
Sandpaper 400 grit
Clean rag
Oil based Primer
Paint Brushes

From a safety point of view, it is often as important to know how to finish a deck wood railing as it is to finish the deck's walking surface or its stair surface. While finishing the deck railing may have an aesthetic impact, it will have an even bigger impact on the deck's safety features. This will be true especially where you have children playing on an elevated deck where the railing is likely to prevent the children from falling from the deck. Finishing the railing will seal the railing and keep weather from deteriorating it and making it unsafe. If you have a deck railing you'd like to finish, here are 6 steps that will help you complete this task.

Step 1 – Prepare the Deck for Being Painted

To keep people from using the deck until it is painted and the paint has dried, run a length of twine or heavy string across entrances to the deck. Make a few signs warning others of wet paint on the deck and attach these signs to the string where they will easily be seen by people approaching the deck.

Step 2 – Rough-Sand the Railing

Use an 80-grit sandpaper and sanding block to remove existing paint or varnish, and to smooth off any rough surfaces on the railing. Avoid using a finer sandpaper that will have a tendency to smooth the railings' surfaces and keep paint or primer from adhering. Be sure to use a sanding block to keep railing surfaces as even as possible. Also, be sure all existing paint is removed. If necessary use a steel brush to remove it.

Step 3 – Fine-Sand the Railing

When you have inspected the railing and are sure all old paint and rough surfaces have been adequately sanded with the coarse sandpaper, begin sanding with the 400-grit sandpaper. Your focus here will be to smooth the railing surface, rather than removing paint or rough surfaces. When finished with the sanding, use a damp cloth and remove all dust from the railing surface from having been sanded. While the railing dries, spread a drop cloth on the deck surface beneath the railing to catch any primer or paint that might drop from the railing.

Step 4 – Apply Paint Primer

When the railing is dry, use a paintbrush and a good quality oil base primer. Apply this primer to the railing surface. By using a high quality brush, you will keep brush fibers from falling onto the newly primed surface.

Step 5 – Apply Paint

Using a clean, high quality brush, apply your paint to the railing surface. By cleaning off excessive paint from your brush as you apply it, you will avoid paint runs on the railing. Check with paint manufacturer’s directions for drying time. When you've allowed the paint to dry, apply additional coats. Finally, when the paint is dry, remove the drop cloth and string and your deck will be ready for use again.