Free Samples | Contact Us
composite decking
Blog

How to Install Composite Staircases?

June 12, 2025

Composite staircases are becoming a popular choice for modern homes and commercial spaces. Compared to traditional wood stairs, WPC decking stairs are more durable and easier to install and maintain. Install once in exchange for longer-lasting use.

Composite decking has a wide range of uses, not only outdoors, but can also be used as outdoor stairs to build and install. Compared to other materials, composite decking stairs offer greater durability, lower maintenance requirements, and fewer inherent disadvantages of having a wood texture.

People who have not used composite decking before may not know how to install composite boards on stairs and whether the installation process will be complicated. The following can guide you on how to properly build stairs with composite boards to ensure long-term use.

What are The Advantages of Composite Staircases?

Composite decking offers many advantages. Stairs made from composite decking combine the natural beauty of wood with the exceptional durability of plastic. Therefore, composite stairs are an ideal alternative to traditional wooden stairs. Their main advantages are as follows:

Weather Resistance

The core advantage of composite staircases is their superior weather resistance. Unlike solid wood, composite decking material will not fade from sun exposure. It also won’t become a food source for termites or other wood pests. This means that composite staircases installed outdoors can maintain consistent performance year-round. You don’t have to worry about damage from seasonal weather changes.

Solid Capped Composite Decking Board CO-03

Capped with an HDPE layer, Capped Composite Decking is made excellent at resisting stains, scratches, weathering, and fading.

View More

Easy Maintenance

Composite staircases require little to no regular maintenance. Traditional wooden stairs usually need to be sanded, repainted, or sealed every year. A composite staircase only needs an occasional wash with soapy water to keep it looking like new. This low-maintenance feature makes them ideal for busy homes and commercial premises. At the same time, it significantly reduces long-term costs.

Long Service Life

Composite staircases excel when it comes to durability. High-quality composite decking materials are not as prone to cracking and warping as natural wood. A properly installed composite staircase can withstand frequent use and heavy lifting. Even after many years of use, it will not suffer from structural loosening or surface wear.

Aesthetics

Composite staircases mimic the grain and tone of a variety of woods. COOWIN’s composite decking materials are also available in a wide range of colors and styles. You can choose a product that perfectly matches your existing décor.

Easy to install

Composite stair components are often designed to be easy to assemble. Manufacturers such as Trex and COOWIN provide installation instructions and accessories. Professional installers are usually able to assemble the entire composite staircase in a short period of time. If you are a DIY enthusiast, you can also achieve satisfactory results by following the correct installation steps.

Environmentally Friendly

Composite decking products are made of wood fiber and recyclable plastic. Using composite staircases reduces dependence on forest resources. At the same time, it provides a valuable way to reuse waste plastics. At the same time, high-quality composite decking materials are produced without adding harmful substances, making them safer to use.

Composite Stair 1

Basic Terms You Should Know

Building stairs with composite boards should be based on safety principles. Durable and safe stairs require care and skill to build. Below are some relevant structural elements.

Stringer

These are the structural members in the staircase that support the treads and risers on the sides. A network of stringers forms the framework of the steps. The spacing between stringers is typically 12 inches (center to center). At least four continuous stringers are required to secure the stair treads.

Treads

The surface that a person’s entire foot touches is called the tread. It needs to be at least 10 inches for steady footing and at least 1 inch thick to support the weight of someone walking on it.

Riser

A stair riser is a near-vertical element in a set of stairs that forms the space between one step and the next. As shown in FIG. They make the stairs look perfect and make the stairs more stable, instead of falling. They must be 0.5 inches thick. When installing the riser, use two screws per stringer.

Composite Stair 2

Preparation Work before Installation

Installation of composite stairs should be carried out through thorough pre-preparation. It mainly includes the following aspects:

Mounting Tool

Standard woodworking tools can be used for our composite boards. If screw fixing is applied, stainless steel or painted screws may be used. We recommend that you use the accessories given for our decking to achieve the optimum effect.

Some of the recommended tools are miter saws with carbide-tip blades, impact drills, screw guns, levels, tape measures, and rubber mallets.

Accurate Measurement and Planning

Before starting the installation, you need to measure the total height of the stair installation area and the length of the available space. These basic dimensions will determine the number of steps, the height and the depth of each step of the staircase. The ideal step height should be between 17-18 centimeters. The depth should be no less than 25 centimeters.

More accurate measurements can be obtained by using a laser range finder. In addition, an extra 10% of the quantity should be purchased when buying materials. Prevent insufficient quantity due to wasteful cutting and installation errors. It is recommended to choose accessories that match the color of the composite deck to keep it beautiful.

Composite Stair 3

Steps to Build Composite Stairs

The installation of composite stairs needs to be done in strict steps. This is the only way to ensure the stability and safety of the final structure. Below is the complete installation procedure.

Knowledge of Local Building Codes and Installation Tools

Stair treads built with composite decking must meet the requirements of your local building codes. Consulting building officials and professionals before construction is recommended.

Spacing & Gapping

  • When using composite boards as stair treads and risers, please follow the composite decking installation gap requirements.
  • The overhang of stair treads should not exceed 1/2’’(13 mm).
  • When top-fixing, keep a distance of at least 1’’(25 mm) between the fixing and the board edge.
  • The spacing between stringers on-center depends on the decking profile.

Starter Board Installation

Fix starter clips on the stringers and put the starter boards in place.

Tread & Riser Installation

Install the next row of tread board with hidden fasteners, no locking clip is needed. Pre-drill pilot holes and top-fix the end tread board to the stringers at a 90° angle. Pre-drill pilot holes and install fascia boards in the same manner. Repeat these steps to finish the installation.

Composite Stair 4

Railing Installation

You may need to install railings depending on the height of use and architectural requirements. Set risers at the start and end of the composite staircase and at every 4-5 steps. Securely attach the risers to the structural frame of the staircase using riser fixers. Risers should be installed perpendicular to the horizontal plane. The use of a laser level is recommended for calibration.

Balustrade crossbar installation requires precise calculation of the angle. Lean the crossbar against the fixed riser. Use an instrument to measure the actual angle of inclination. The cuts at the ends of the crossbar need to match this angle. Composite railing systems are often designed with pre-drilled holes. This design makes the railing both easy to install and aesthetically pleasing.

Railing infill pieces come in a variety of forms, including vertical bars, horizontal bars, glass panels, or mesh. Vertical bars are the most common choice. They must be installed no more than 10 centimeters apart to prevent children’s heads from getting stuck.

Conclusion

Composite staircases not only look great, but they are also more resistant to harsh weather, pests and moisture. By understanding the entire process of installing composite staircases, you can create a composite stair system that is both beautiful and durable. If you have any needs and questions about composite decking materials, please contact us. COOWIN can provide professional composite decking products and services.

FAQ

What are The Advantages of Composite Staircases over Traditional Wooden Stairs?

Composite staircases offer several significant advantages. These include:

  • Durability: Composite decking material is resistant to moisture and weather. It can last up to 3-5 times longer than traditional wood.
  • Low Maintenance: Composite staircases do not require regular sanding, painting, or sealing.
  • Stability: Composite staircases are not easily affected by changes in temperature and humidity, and are not easily cracked or deformed.
  • Safety and Environmental Protection: Composite staircases have good anti-slip performance and are safer to use.
  • Beautiful and Long-lasting: Composite deck materials are not easy to wear and fade, and can remain beautiful for a long time.

Is The Composite Staircase Anti-slip?

The non-slip performance of the stairs is especially important. You can choose composite decking material with a non-slip texture on the surface. It has a high coefficient of friction and is safer. In addition, there are other anti-slip measures you can take. For example, install temporary anti-slip mats during the winter months.

Related Post

author avatar
Galen Content Writer
Galen is a content creator and decorator with five years of experience designing home decor. In his daily life, Galen is constantly on the lookout for the latest, great examples of house design and further optimizes his solutions. Additionally, he writes articles related to outdoor design, interior design, and architectural decorating materials to help brands build more engaging relationships with their audiences.
Latest Posts
Read More >>
Composite Fencing for Coastal and Saltwater Environments Composite Fencing for Coastal and Saltwater Environments
September 9, 2026
Composite fencing can be a strong choice near the coast. Capped boards resist moisture, rot, insects, and weathering.
What You Need to Know About Deck Ideas What You Need to Know About Deck Ideas
September 8, 2026
Building an outdoor area that matches your home and your tastes is appealing. A properly built deck can bring you more enjoyment of the outdoors.
What Is The Difference Between Siding And Cladding? What Is The Difference Between Siding And Cladding?
September 7, 2026
Siding and cladding both cover the outside of a building, but they differ in how they are fixed and how they handle moisture.
6 Best Alternatives to Wooden Decking 6 Best Alternatives to Wooden Decking
September 4, 2026
This piece talks about the best alternatives to wood decking and lists the pros and cons of each. Now, let's explore deck materials together.