Thermally Modified Wood for Covered Patio Walls in Denver, CO

Understanding Thermally Modified Wood for Wall Applications

Thermally modified wood undergoes a high-heat treatment process that alters its cellular structure. This process aims to reduce the wood's ability to absorb moisture, which contributes to increased dimensional stability and a reduced tendency to swell, shrink, or cup when exposed to changes in humidity. For covered patio walls, where humidity fluctuations can still occur even with overhead protection, this stability is a key advantage.

The thermal modification process also darkens the wood, creating a richer, often more uniform color. This can be a desirable aesthetic for a covered outdoor space, offering a sophisticated backdrop to furniture and landscaping. While the wood's natural properties are enhanced, it's important to remember that it remains a wood product and will interact with its environment.

Selecting the Right Profile for Covered Patio Walls

The profile of the thermally modified wood planks significantly impacts the final look and installation method. Common profiles suitable for covered patio walls include tongue-and-groove, shiplap, and square-edge boards. Each offers a different aesthetic and installation characteristic.

Tongue-and-groove profiles create a tight, interlocking fit, which can provide a clean, continuous surface. This is often chosen for a more finished, interior-like appearance in covered outdoor spaces. Shiplap offers a distinct shadow line and a slightly more rustic or contemporary feel, depending on the reveal gap. Square-edge boards, while simpler, require precise spacing and can be installed with an open-joint rainscreen approach, even in covered areas, to allow for air circulation and drainage behind the cladding.

Consider the visual impact you desire. A narrow, V-groove tongue-and-groove might create a refined, linear look, while a wider shiplap could offer a bolder, more substantial presence. The choice of profile also influences fastener selection and visibility, with some systems allowing for concealed fasteners.

Finishing and Appearance Options

Thermally modified wood can be left unfinished to weather naturally to a silver-gray patina, or it can be treated with a finish to maintain its original color or enhance its tone. For covered patio walls, where direct sun exposure may be reduced but not eliminated, the rate of weathering can be slower and less uniform than on fully exposed surfaces.

If you opt for a finish, choose a product designed for exterior wood, such as a penetrating oil or a UV-resistant stain. These finishes can help protect the wood from UV degradation and moisture absorption, while also allowing for easier cleaning. Regular reapplication will be necessary to maintain the finish's appearance and protective qualities. Always follow the finish manufacturer's instructions for application and maintenance.

Installation Considerations for Covered Patio Walls

While covered patio walls offer some protection, proper installation is still crucial for longevity. Ensure adequate ventilation behind the cladding, even if it's not a full rainscreen system. A minimum air gap, typically achieved with furring strips, allows moisture to escape and helps prevent condensation buildup, which is important for any wood application.

Fasteners should be corrosion-resistant, such as stainless steel, to prevent staining of the wood and ensure long-term structural integrity. For concealed fastener profiles like tongue-and-groove, ensure the fasteners are driven correctly to avoid splitting the wood. For face-fastened applications, pre-drilling may be necessary, especially near board ends, to prevent cracking.

Consider how the wall will terminate at corners, the ceiling, and the base. Flashing and trim details are important to manage any water ingress, even in covered areas, and to provide a clean, finished appearance. Allow for expansion and contraction of the wood by following manufacturer-recommended spacing guidelines, especially for longer runs.

Project Example: Covered Patio Wall with Thermally Modified Wood

Imagine a covered patio measuring 12 feet wide by 10 feet deep, with a back wall and two side walls that are 8 feet tall. The back wall is 12 feet long, and each side wall is 10 feet long. You decide on a horizontal shiplap profile for the thermally modified wood, where each board is 5.5 inches wide (nominal 6-inch board) and 8 feet long.

First, calculate the total linear footage of walls: 12 ft (back) + 10 ft (side 1) + 10 ft (side 2) = 32 linear feet. The total area is 32 ft * 8 ft height = 256 square feet. Each 8-foot-long board, with a 5.5-inch exposed face, covers (5.5 / 12) * 8 = 3.67 square feet. To cover 256 square feet, you would need approximately 256 / 3.67 = 69.7 boards. Accounting for cuts and waste (typically 10-15% for wood cladding), you might plan to purchase around 77-80 boards.

The shiplap boards would then be installed horizontally, starting from the bottom, overlapping each course and securing with corrosion-resistant fasteners into the furring strips. Careful attention would be paid to corner details, using mitered joints or trim pieces for a clean finish. This approach combines the aesthetic appeal of the thermally modified wood with a robust installation method suitable for a covered outdoor environment.

Before you order

• Confirm the specific thermally modified wood species and profile are approved for vertical wall applications.
• Assess the degree of exposure to sun, rain, and humidity for your covered patio walls.
• Decide on a finish: natural weathering or a protective oil/stain.
• Plan for proper ventilation behind the cladding (e.g., furring strips).
• Select appropriate corrosion-resistant fasteners.
• Detail how corners, top, and bottom edges will be finished.
• Estimate material quantities, including waste factor.
• Consider the aesthetic impact of board width and profile on the overall look.

Confirm installation details, approved uses and warranty terms in the current instructions for the exact product and profile. Your installer should verify the substrate, structure and applicable project requirements.

This is a planning guide for projects in Denver, CO. Ask our team to confirm availability, delivery to your ZIP code and which branch can support your order.

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