How to Install Solar Post Caps on Decks, Fences, and Deck Stair Posts

Mark Petersen Written By: Mark Petersen

Solar Post Light Caps

Outdoor lighting can add beauty and function to any deck, and installing solar post cap lights is one of the easiest and most cost-effective ways to make your deck shine. But not all decks are built the same or have the same lighting needs, and not all solar post cap lights are designed with the same purpose in mind. This article will provide the information you need to find the best solar lighting solution for your unique deck.

What is a post cap?

Post Cap Top

Post caps are not just decorative elements. Whether on a wood fence post or a wood deck railing post, the primary function of any post cap is to protect the top of the post from absorbing rainwater. The exposed end grains on the tops of posts absorb water like a sponge, which means they need more protection than the sides of posts. It doesn’t matter if a post is made from a naturally weather resistant wood like cedar, or made of chemically treated wood, installing a post cap that sheds water and keeps the top of the post dry reduces wood rot and splitting and could possibly add decades to the life of a post.

Advantages of Solar post cap lights

Post Cap Light Internal

Outdoor lighting can prevent trips and falls and add a customizable ambiance to any deck. If you are building a deck that has other low-voltage features, then installing low-voltage powered post cap lights might be a good solution. However, installing the wires required to power low-voltage lighting can be time consuming, and concealing the wires on existing decks can be tricky. Whereas installing wire-free solar lights can literally take a few minutes each. And since you will want to protect your post with some kind of post cap, adding solar post cap lights can add very little cost to a new deck build.

What types of solar post cap lights are available?

Virtually all solar post cap lights will have small solar panels on the top. Beyond that similarity, there are a huge number of styles and colors available, and solar post cap lights can be made of metal, plastic, or composite materials. Cap lights are designed to either illuminate outward or downward and built to fit either a 4x4 or 6x6 post.

It’s important to keep in mind that when a low-maintenance sleeve is installed over a wood post, the size of the post becomes bigger. Some solar caps are designed to fit wood posts, some are designed to fit posts with sleeves, and some cap lights are universal and have adapters that allow them to fit both. The brightness and color temperature on some cap lights are adjustable, and others are equipped with motion sensors.

Which solar post caps lights are best for my deck?

Post Cap Light Style

Whether you live in a home that features Craftsman, Victorian, or Mid-Century Modern architecture, you are almost guaranteed to find a style and color of light that both complements your homes aesthetics and adds to the continuity of your other decking materials.

In addition to the proper size and most appropriate style, the other most important consideration when choosing your lights is the direction of the light. If there are benches or chairs that place people near to and at eye level with a post, you could avoid having light shine directly in their eyes by choosing cap lights that shine down instead of out in that area.

How bright are solar post cap lights?

The brightness of a solar post cap light primarily depends on how many LEDs (Light-Emitting Diodes) it has. Some lights emit as little as 5 lumens and some well over 200. For comparison, a 60-watt incandescent bulb emits about 800 lumens. Lumen ratings don’t always take into account the lens that is covering the LEDs.

A frosted lens will reduce the amount of effective lumens more than a clear lens will. Some solar post cap lights offer the ability to adjust both the brightness and color temperature as well. All lights have a particular color temperature that is rated on a Kelvin scale. A light rated at 2700k will appear more yellow, while a 6500k light will appear more blue/white.

How long will solar deck post cap lights last?

Runtime, battery life, and the life of the light fixture itself will vary greatly depending on the quality of the light and the batteries that power them, but here are some general guidelines.

  • Fully charged batteries should generate about 6-10 hours of light per night. Depending on the battery capacity and voltage, this could be longer with a full charge.
  • Rechargeable batteries typically need about 6-8 hours of direct sunlight to charge.
  • The average lifespan of rechargeable batteries is between 1-4 years.
  • A high-quality solar post cap light should last for 6 years or more.

How much do solar post caps cost?

Solar post cap lights are available at prices ranging from under $10 to over $300. The size, type of materials, level of craftsmanship, number of options, and length of the warranty will dictate the price you pay. A light built to fit a 6x6 post will cost more than the same style light built to fit a 4x4 post.

A $10 light will likely be made out of plastic that will fade, include batteries that won’t last as long, and offer a warranty of 30 days or less.

Premium lights will be made of longer-lasting materials, can have brightness and temperature controls, and some will offer warranties that last 2 years or longer. Some manufacturers sell solar post cap lights in packs containing multiple lights for less money per unit. Rechargeable batteries are usually included with new lights, and replacement batteries cost between $1-$4 each.

How to install a solar post cap light

How To Install A Solar Cap Light

Installing solar deck post cap lights is one of the easier DIY project you’ll come across. Most solar lights can be installed in less than five minutes. If you’ve just bought some new solar post cap lights, here’s a step-by-step guide on how to install them.

  • Turn the cap upside down or separate the top half from the base.
  • If there is a switch, turn it to “ON” mode, and adjust the lights to the desired brightness and light temperature if these options are available.
  • Install the batteries or pull the tab that will activate the batteries.
  • Test fit the cap to make sure it is the proper size and then add or remove the adapter for those universal units designed to fit posts with and without sleeves.

Secure the cap to the post with either adhesive or screws depending on your specific model.

Solar Post Cap Internal Display

Some products require a drill; some can be installed with just a screwdriver, and others require no tools at all.

Where should solar post cap lights be installed?

Where you choose to install a solar post cap light will depend on what you are trying to accomplish. If you want as much lighting as possible, you might want to install a high-output light on every post, making sure to avoid installing lights where they might shine in people’s eyes. If the goal is to add mood or accent lighting only, then try installing lights on every other or every third post and add more if more light is needed. If you are only installing one or two lights and the location is not important, try to choose a spot where the sun shines for more hours every day. Heavily shaded locations might reduce charging performance by as much as 50-80%. Installing solar lights on stair railing posts is a great way to illuminate deck stairs and reduce the chance of a fall.

How to maintain solar post cap lights

How To Maintain Solar Post Cap Lights

Maintaining solar post cap lights is easy, and the cleaner the solar panels and lens caps are the more light they will produce. Just periodically wipe down the outside of the light using a damp rag. Using harsh cleaning chemicals could damage the solar panels and cause lens caps to become foggy. If you live in a cold climate, you can extend the life of your rechargeable batteries by either shutting them off or removing them during the colder months when you won’t be using your deck.

To find solar deck lighting at a nearby retailer, use the Decks.com Find a Retailer tool.

See Other Ideas about Outdoor Deck Lighting

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