Understanding Thermally Modified Wood for Walls
Thermally modified wood undergoes a high-heat treatment process that alters its cellular structure. This modification generally enhances the material's stability and resistance to decay, making it a suitable choice for various exterior applications, including covered patio walls. For walls that are largely protected from direct rain, snow, and prolonged UV exposure, the enhanced stability of thermally modified wood can contribute to a consistent appearance and reduced movement over time.
While thermally modified wood is known for its durability, it's important to differentiate its use in covered applications from fully exposed facades. The 'covered' aspect means less direct impact from harsh elements, which can influence choices regarding finishes and the specific species of thermally modified wood selected. Common species for thermal modification include spruce, pine, and ash, each offering distinct grain patterns and characteristics.
Selecting Profiles and Visual Effects
The profile of the thermally modified wood planks significantly impacts the final aesthetic of your covered patio wall. Different profiles create varying shadow lines, textures, and overall visual rhythms. For covered patio walls, where the details might be viewed at closer range, profile selection becomes a key design element.
Common profiles include tongue and groove, shiplap, and board and batten. Tongue and groove profiles offer a smooth, continuous surface with minimal gaps, creating a clean and modern look. Shiplap provides a distinct overlap that produces subtle shadow lines, adding depth and a more traditional or rustic feel. Board and batten, while often used for fully exposed siding, can also be adapted for covered walls to create a strong vertical emphasis with deeper shadow play. Consider the scale of your patio and the desired ambiance when making your selection.
For example, the NORX brand offers a range of thermally modified wood profiles suitable for cladding and wall applications. These often include standard tongue and groove or shiplap options, which are well-suited for creating defined lines and textures on a covered patio wall. You can explore options like their thermally modified spruce or pine products.
Finishing Options and Maintenance for Covered Walls
Even for covered patio walls, applying a finish to thermally modified wood is a consideration. While the thermal modification process improves dimensional stability, a finish can protect the wood from UV degradation, prevent premature graying, and enhance its natural color. For covered applications, the finish may endure longer than on fully exposed surfaces, potentially requiring less frequent reapplication.
Clear penetrating oils or stains can deepen the wood's natural tone and offer UV protection. If a specific color is desired, semi-transparent or opaque stains can be used. It's important to choose a finish designed for exterior wood and to follow the manufacturer's application guidelines. Regular cleaning to remove dust, pollen, and debris will help maintain the finish and the wood's appearance over time. Annual inspection for any signs of wear or damage to the finish is also recommended.
Attachment and Substructure Considerations
Proper attachment is crucial for the longevity and stability of thermally modified wood on covered patio walls. The substructure to which the wood is attached must be sound, level, and capable of supporting the cladding. This typically involves furring strips or a rainscreen system, even in covered environments, to allow for air circulation and moisture management.
Furring strips provide a consistent surface for fastening and create a small air gap behind the cladding. This gap can help prevent moisture accumulation and promote drying, which is beneficial even in covered areas. Fasteners should be corrosion-resistant, such as stainless steel screws, and long enough to penetrate securely into the substructure. Hidden fastening systems, often used with tongue and groove or shiplap profiles, can provide a clean, fastener-free appearance on the finished wall. Always refer to the specific product's installation guidelines for recommended fastener types and spacing.
Project Example: Covered Patio Wall in Traverse City, MI
Consider a hypothetical covered patio in Traverse City, MI, measuring 15 feet wide by 8 feet high. The homeowner desires a modern aesthetic with subtle shadow lines. They select a thermally modified spruce shiplap profile, with individual planks measuring 5.5 inches wide (including the overlap) and supplied in 12-foot lengths. The project calls for a natural oil finish to enhance the wood's inherent color.
To calculate the material needed, first determine the total wall area: 15 ft * 8 ft = 120 square feet. Next, calculate the coverage area of a single plank: 5.5 inches / 12 inches/foot * 12 feet = 5.5 square feet. Dividing the total area by the plank coverage gives approximately 120 sq ft / 5.5 sq ft/plank = 21.8 planks. Accounting for cuts, waste, and potential future repairs, it's prudent to order an additional 10-15%. Therefore, ordering 25-26 planks would be a reasonable estimate. This calculation assumes minimal waste from cuts, for example, if the 8-foot height allows for one 8-foot cut and a reusable 4-foot offcut from each 12-foot plank, or if the 15-foot width allows for two 7.5-foot pieces. A detailed cut plan would optimize material usage.
The attachment would involve vertical furring strips, spaced according to manufacturer recommendations, secured to the existing patio structure. Stainless steel trim head screws, angled through the tongue or hidden in the overlap of the shiplap, would provide a secure and discreet fastening solution. The natural oil finish would be applied after installation, following the product's curing instructions.
Before you order
- Confirm thermally modified wood species and profile are approved for wall applications.
- Assess the degree of 'cover' for the patio wall: how much direct rain/sun exposure will it receive?
- Select a finish (oil, stain, or none) based on desired appearance and maintenance expectations.
- Verify compatibility of chosen fasteners with thermally modified wood and substructure.
- Plan for a substructure (e.g., furring strips) that allows for drainage and ventilation.
- Measure the wall dimensions accurately, accounting for openings, corners, and potential waste.
- Consider the aesthetic impact of profile choice on the overall patio design.
- Review local building practices or recommendations for exterior wood cladding in Traverse City, MI.
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 Traverse City, MI. 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 left unfinished on a covered patio wall?
Yes, thermally modified wood can be left unfinished. Without a finish, it will gradually weather to a silver-gray patina over time due to UV exposure, even in a covered area, though at a slower rate than fully exposed wood. If you prefer to maintain the wood's original color, a UV-protective finish is recommended.
Does thermally modified wood require a rainscreen system for covered patio walls?
While covered patio walls are protected from direct precipitation, using furring strips to create an air gap (part of a rainscreen assembly) is still beneficial. This gap allows for air circulation, helps manage any incidental moisture, and contributes to the overall stability and longevity of the cladding by promoting drying.
How do I clean thermally modified wood on a covered patio wall?
Regular cleaning with a soft brush or cloth and mild soap and water is generally sufficient for covered patio walls. Avoid harsh chemicals or high-pressure washers, which can damage the wood or its finish. Always rinse thoroughly with clean water.
Plan Your Thermally Modified Wood Project
Ready to enhance your covered patio walls with thermally modified wood? Request a material quote today. Provide your project dimensions, desired profile, and ZIP code to confirm current availability and service options.
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