Understanding Thermally Modified Wood for Wall Applications
Thermally modified wood undergoes a high-temperature process that alters its cellular structure. This treatment enhances the wood's stability, reducing its tendency to swell, shrink, or warp when exposed to changes in humidity. For covered patio walls, where indirect moisture and temperature shifts can still occur, this inherent stability is a significant advantage, helping to maintain a consistent appearance over time.
The modification process also imparts a rich, darker tone to the wood, which can range from a honey brown to a deep chocolate, depending on the species and treatment intensity. This color is natural and extends throughout the wood, meaning minor surface scratches are less noticeable than with a stained surface. While it can be left unfinished to weather to a silver-gray patina, applying a finish can help preserve its original color and offer additional protection.
Selecting the Right Profile for Covered Patio Walls
The profile of the thermally modified wood boards plays a crucial role in the final appearance and installation method for your covered patio walls. Common profiles include Tongue & Groove (T&G), Shiplap, and Square Edge.
Tongue & Groove profiles offer a secure, interlocking fit, creating a smooth, continuous surface with subtle V-grooves or square edges depending on the milling. This profile is often chosen for a more finished, interior-like aesthetic on covered walls. Shiplap provides an overlapping joint that creates distinct shadow lines, adding depth and texture to the wall. It allows for some natural movement of the wood while maintaining a tight visual seam. Square edge boards are installed with a visible gap between them, often in a rainscreen-like assembly, which can create a modern, slatted look. The choice of profile should align with your desired aesthetic and the level of visual continuity you aim to achieve.
Finishing Options and Appearance Retention
While thermally modified wood is known for its durability, applying a finish can enhance its appearance and provide an extra layer of protection, particularly in a climate like Lincoln, NE, where seasonal changes can still affect outdoor materials. Finishes can help maintain the wood's initial rich color and offer UV protection, slowing the natural weathering process.
Clear or semi-transparent oil-based finishes are popular choices as they penetrate the wood, nourishing it while allowing its natural grain to show through. These finishes typically require reapplication every few years, depending on exposure. Alternatively, for those who appreciate the natural aging process, the wood can be left unfinished. It will gradually weather to an elegant silver-gray patina, a common and desired aesthetic for many outdoor wood applications. Understanding this natural color change is important for long-term design planning.
Attachment and Substructure Considerations
Proper attachment is essential for the longevity and stability of your thermally modified wood patio walls. For covered applications, a sturdy substructure, typically consisting of wood furring strips or metal channels, is required. These strips provide a level surface for attachment and create an air gap behind the wood, which can help manage incidental moisture and promote ventilation. The spacing of the furring strips should correspond to the length and thickness of your chosen wood boards, ensuring adequate support.
Fasteners should be corrosion-resistant, such as stainless steel screws, to prevent staining and ensure long-term holding power. Hidden fastener systems, often used with T&G or shiplap profiles, can provide a clean, fastener-free appearance on the surface of the boards. For square edge profiles, face fastening with screws can be part of the design aesthetic. Always follow manufacturer recommendations for fastener type, size, and spacing to ensure proper installation and performance.
Worked Example: Designing a Covered Patio Feature Wall
Consider a covered patio in Lincoln, NE, where you want to create a feature wall measuring 10 feet wide by 8 feet high using thermally modified wood shiplap. You've selected NORX thermally modified pine shiplap boards, which are typically available in 6-inch nominal widths (actual coverage 5.5 inches) and various lengths, including 10-foot and 12-foot boards. For this example, we'll assume 10-foot boards are preferred to minimize field cuts.
First, calculate the required coverage area: 10 feet x 8 feet = 80 square feet. To determine the number of boards, divide the total width by the coverage width of one board: 10 feet (120 inches) / 5.5 inches per board = 21.82 boards. Since you cannot purchase partial boards, you would need 22 boards. Each board needs to be 8 feet long for the vertical installation. If you are using 10-foot boards, each board will yield one 8-foot piece with a 2-foot offcut.
For a horizontal installation, you would need 8 feet (96 inches) / 5.5 inches per board = 17.45 boards. So, 18 boards. Each board needs to be 10 feet long for the horizontal installation. If you are using 10-foot boards, each board will be used in full.
For vertical installation, horizontal furring strips at similar spacing would be needed. This example assumes a straightforward installation; complex designs, window/door openings, or specific detailing would require more detailed calculations and a cut plan to optimize material use and account for waste.
Before you order
- Determine the desired aesthetic: smooth, continuous (T&G) or textured with shadow lines (Shiplap/Square Edge).
- Confirm the specific thermally modified wood species and profile are approved for wall applications.
- Decide on a finish: preserve natural color with an oil, or allow to weather to silver-gray.
- Plan the substructure: furring strip material, spacing, and ventilation considerations.
- Select appropriate corrosion-resistant fasteners: visible or hidden.
- Measure the area accurately, accounting for waste and specific board lengths.
- Consider how corners, edges, and transitions will be detailed.
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 Lincoln, NE. Ask our team to confirm availability, delivery to your ZIP code and which branch can support your order.
Questions to help you decide
Can thermally modified wood be painted for covered patio walls?
While thermally modified wood can be painted, it is generally recommended to use stains or clear finishes. The dimensional stability of thermally modified wood means it moves less than untreated wood, which can help paint adhere better. However, many choose thermally modified wood for its natural beauty and the way it takes stains, allowing the wood grain to remain visible. If painting, ensure the paint is suitable for exterior wood and follow manufacturer instructions for preparation and application.
How does the Lincoln, NE climate affect thermally modified wood on a covered patio?
Lincoln, NE experiences significant seasonal temperature fluctuations, including hot summers and cold winters, along with varying humidity levels. While covered patio walls are protected from direct rain and snow, they are still exposed to ambient humidity and temperature changes. Thermally modified wood's enhanced dimensional stability is beneficial in this climate, as it resists warping and checking more effectively than untreated wood when responding to these environmental shifts. A quality finish can offer additional protection against UV exposure and moisture.
What maintenance is required for thermally modified wood covered patio walls?
Maintenance for thermally modified wood on covered patio walls is generally low. If left unfinished, the wood will naturally weather to a silver-gray and requires no regular finishing. If a finish is applied, periodic reapplication (typically every 2-5 years, depending on the product and exposure) will be necessary to maintain the desired color and protection. Regardless of finish, occasional cleaning with mild soap and water can help remove dirt, dust, and any mildew that may accumulate in shaded areas.
Plan Your Thermally Modified Wood Patio Wall Project
Ready to enhance your covered patio in Lincoln, NE? Request a material quote for thermally modified wood. Provide your project dimensions, desired profile, and ZIP code to confirm current availability and service options. We can help you identify the right materials for your specific design vision.
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