Thermally Modified Wood for Covered Patio Walls in Chicago, IL

Why Thermally Modified Wood for Covered Patio Walls?

Thermally modified wood undergoes a high-temperature treatment process that alters its cellular structure. This process aims to improve the wood's dimensional stability and reduce its susceptibility to moisture absorption. For covered patio walls, where humidity fluctuations can still occur despite overhead protection, this enhanced stability can be a significant advantage, helping to minimize warping or cupping.

The thermal modification process also imparts a consistent, rich brown tone throughout the wood, which can deepen with certain finishes or age to a silver-gray if left unfinished. This natural coloration can complement various architectural styles and outdoor living spaces. Furthermore, thermally modified wood is often selected for its natural aesthetic, providing the warmth and texture of real wood without requiring the same level of intensive maintenance as some untreated wood species in similar applications.

Selecting the Right Profile and Species

Thermally modified wood is available in various profiles, each creating a different visual effect. For covered patio walls, common profiles include tongue-and-groove, shiplap, and square-edge boards. Tongue-and-groove profiles offer a tight, seamless appearance, often used for a more contemporary or refined look. Shiplap creates a distinct shadow line and can lend a classic or rustic feel. Square-edge boards, when installed with a gap, can provide an open, slatted aesthetic.

Species commonly used for thermal modification include Ash and Poplar. Thermally modified Ash, such as NORX Thermally Modified Ash, is known for its distinct grain pattern and durability. Thermally modified Poplar, like the US4 Thermally Modified Poplar, offers a lighter initial color that can be stained or left to weather. The choice of profile and species will depend on the desired aesthetic and the overall design of the covered patio space. Consider how light will interact with the chosen profile to create shadows and highlights on the wall.

Finishing and Maintenance for Covered Patio Walls

While thermally modified wood exhibits improved stability, applying a finish can further enhance its appearance and offer an additional layer of protection against UV exposure and moisture. For covered patio walls, a clear penetrating oil or a UV-resistant stain can help maintain the wood's initial color or achieve a desired hue. If left unfinished, the wood will naturally weather to a soft silver-gray over time. The rate of weathering can be slower in a covered application compared to fully exposed siding.

Maintenance for finished thermally modified wood typically involves periodic cleaning and reapplication of the chosen finish, following the manufacturer's recommendations. Unfinished wood requires less frequent attention, primarily limited to cleaning as needed to remove dirt or debris. Regular inspection of the walls can help identify any areas that might require touch-ups or more thorough cleaning.

Planning Your Covered Patio Wall Layout

The layout of your thermally modified wood on covered patio walls can significantly impact the final look. Consider whether to run the boards horizontally, vertically, or even diagonally. Horizontal installation can make a space feel wider, while vertical boards can emphasize height. Diagonal patterns offer a dynamic visual interest but may involve more complex cuts and material waste.

When planning, measure the dimensions of your wall meticulously. Account for any openings such as windows or doorways, and plan your board lengths to minimize waste. For a seamless look, consider how boards will meet at corners. Using mitered joints can create a clean transition, while butt joints with trim can offer a more traditional appearance. Always refer to product documentation for recommended fastening methods and spacing requirements to ensure proper installation and allow for any minor wood movement.

Worked Example: Covered Patio Wall with Thermally Modified Ash

Let's consider a hypothetical covered patio wall measuring 10 feet wide by 8 feet high. We've chosen NORX Thermally Modified Ash in a 5.5-inch face width (nominal 1x6) tongue-and-groove profile, installed horizontally. Each board is assumed to be 12 feet long for purchasing. We need to cover an area of 80 square feet (10 ft x 8 ft).

First, calculate the number of courses needed vertically: 8 feet (96 inches) / 5.5 inches per board face = approximately 17.45 courses. We will need 18 full courses. Since the boards are 10 feet wide and purchased in 12-foot lengths, each 12-foot board can yield one 10-foot section with 2 feet of offcut. For 18 courses, we would need 18 boards if there were no reusable offcuts. However, a 12-foot board can also be cut to provide two sections for a shorter wall or used to start a new course. For a 10-foot width, each course requires one 10-foot piece. Therefore, we would need 18 boards if we assume minimal reuse of offcuts. If we were installing vertically, the calculation would be 10 feet (120 inches) / 5.5 inches per board face = approximately 21.8 courses. We'd need 22 courses, each 8 feet long. If purchasing 12-foot boards, each board could yield one 8-foot piece with 4 feet of offcut, or two 8-foot pieces could be cut from a 16-foot board. Always plan for extra material (typically 10-15%) for cuts, waste, and unforeseen issues. This calculation is for area coverage; actual purchase quantity depends on available board lengths and a detailed cut plan.

For this example, using 12-foot boards for a 10-foot wide wall, we would purchase 18 boards to ensure enough material for all 18 courses, allowing for some trimming and potential waste. The total linear footage needed is 18 courses * 10 feet/course = 180 linear feet. With 12-foot boards, 180 linear feet / 12 feet/board = 15 boards. Adding 10% for waste, we would order approximately 17 boards. This example highlights the importance of precise measurements and considering board lengths for efficient material use.

Before you order

• Determine the desired aesthetic: rustic, modern, or traditional?
• Choose between horizontal, vertical, or diagonal board orientation.
• Select a thermally modified wood species (e.g., Ash, Poplar) and profile (tongue-and-groove, shiplap, square-edge).
• Decide on a finish: clear oil, stain, or natural weathering.
• Measure wall dimensions accurately, accounting for windows, doors, and corners.
• Calculate material quantities, including a waste factor (10-15%).
• Confirm appropriate fastening methods for your chosen profile and substructure.
• Plan for ventilation behind the cladding, if recommended for your specific assembly.
• Consider how the new wall will integrate with existing patio elements and landscaping.

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 Chicago, IL. Ask our team to confirm availability, delivery to your ZIP code and which branch can support your order.

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