Why Choose Thermally Modified Wood for Covered Patio Walls?
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 in turn can improve its dimensional stability. For covered patio walls, this means a material that is less prone to warping, cupping, or checking compared to untreated wood, even with seasonal changes.
The treatment also often results in a richer, darker tone throughout the wood, offering a consistent color that can be maintained with appropriate finishes or allowed to weather naturally. Its inherent characteristics make it suitable for applications where a wood aesthetic is desired but with improved performance in outdoor environments, even when sheltered.
Understanding Profiles and Aesthetics for Wall Applications
Thermally modified wood is available in various profiles, each creating a different visual effect on a wall. Common profiles include tongue-and-groove, shiplap, and square-edge boards. Tongue-and-groove profiles create a tight, interlocking joint, often preferred for a smooth, continuous surface. Shiplap offers a distinctive shadow line and can be installed horizontally or vertically.
Square-edge boards, when installed with a visible gap, can create a more modern, open aesthetic. The choice of profile impacts not only the appearance but also how water might shed from the surface, even on a covered wall. Consider the desired shadow lines, the overall architectural style of your patio, and how the profile will complement other materials.
For a clean, modern look, a NORX thermally modified spruce shiplap profile can provide crisp lines. If a more traditional, solid wood appearance is preferred, a tongue-and-groove profile might be more suitable. Explore options like Maximo Accoya for specific performance needs. The direction of installation (horizontal or vertical) also plays a significant role in the perceived height and width of the patio space.
Finishing and Maintenance Considerations
While thermally modified wood is more stable than untreated wood, it will still naturally weather and change color over time if left unfinished. Many homeowners choose to apply a finish to maintain the original color or to introduce a specific hue. Oil-based finishes or stains designed for exterior wood are common choices.
For covered patio walls, the finish may last longer than on fully exposed surfaces due to reduced direct UV exposure and precipitation. However, reapplication will still be necessary over time to preserve the color and provide ongoing protection. If a natural silver-gray patina is desired, no finish is required, though regular cleaning may still be beneficial.
The maintenance schedule will depend on the chosen finish, the specific exposure conditions of your covered patio, and your aesthetic preferences. Always follow the finish manufacturer's instructions for application and reapplication.
Attachment Methods and Substructure
Proper attachment is crucial for the longevity and appearance of thermally modified wood walls. Fastening methods typically include face fastening or concealed fastening systems. Face fastening involves driving fasteners through the face of the board into the substructure, which can be visible but offers a secure attachment. Concealed fastening systems, often used with tongue-and-groove or specific shiplap profiles, hide the fasteners for a cleaner look.
The substructure behind the thermally modified wood needs to be sound and provide adequate support. This typically consists of furring strips or blocking installed over the existing wall sheathing or framing. These strips also create a small air gap, which can help with moisture management and ventilation behind the wood cladding. Ensure that all fasteners are corrosion-resistant, such as stainless steel, to prevent staining and ensure long-term hold.
Always confirm the specific fastening recommendations for the chosen thermally modified wood profile and local building practices. The spacing of furring strips should align with the length of the wood boards and the expected load on the wall.
Hypothetical Project Example: Covered Patio Wall in Boise
Consider a hypothetical covered patio in Boise, ID, measuring 12 feet wide by 8 feet high, with two walls to be clad in thermally modified wood. The homeowner desires a modern aesthetic with subtle shadow lines. They select a 5.5-inch face-width NORX thermally modified spruce shiplap profile, installed horizontally.
Each board is 16 feet long. To cover an 8-foot high wall, approximately 17.5 boards would be needed per vertical stack (8 feet * 12 inches/foot / 5.5 inches/board = 17.45 boards). Rounding up for cuts and waste, 18 boards are planned per vertical stack. For a 12-foot wide wall, each 16-foot board can be cut into one 12-foot piece and one 4-foot offcut. The 4-foot offcuts may be usable for other sections or as starter/ender pieces on another wall if dimensions align.
For the 12-foot wall: 18 boards high x 1 stack wide = 18 boards. For two such walls, 36 boards would be a starting estimate. Due to the 16-foot length, each board yields one 12-foot piece, with 4 feet of potential usable offcut. However, to maintain consistent appearance and minimize visible joints, it's often better to order full-length boards for each run where possible. For two 12-foot wide walls, 36 boards of 16-foot length would provide coverage with some allowance for cuts. It is always recommended to add 10-15% for waste, cuts, and future repairs. This would bring the total to approximately 40-42 boards. The homeowner also plans to use a semi-transparent oil finish to maintain the wood's warm tone.
The substructure would consist of vertical furring strips, spaced according to the manufacturer's recommendations for horizontal cladding, typically 16 or 24 inches on center, attached to the existing framing. Fasteners would be stainless steel trim screws, discreetly placed in the shadow line of the shiplap profile for a concealed look.
Before you order
- Verify local building codes for exterior wall cladding, even on covered patios.
- Confirm the specific thermally modified wood species and profile are approved for wall applications.
- Determine desired aesthetic: natural weathered look or maintained color with a finish.
- Select appropriate finish product, if applicable, considering UV exposure and maintenance.
- Plan the substructure (furring strips, blocking) to ensure proper support and ventilation.
- Choose corrosion-resistant fasteners suitable for the wood type and attachment method.
- Measure project dimensions accurately and calculate material quantities, adding waste factor.
- Consider the direction of board installation (horizontal or vertical) and its visual impact.
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 Boise, ID. 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?
While thermally modified wood can be painted, it is often chosen for its natural wood appearance. If painting, ensure the paint is suitable for exterior wood and follow the manufacturer's recommendations for surface preparation and application. The enhanced stability of thermally modified wood can contribute to better paint adhesion and longevity compared to untreated wood.
Does thermally modified wood require a rainscreen system for covered patios?
For covered patio walls that are not directly exposed to driving rain, a full rainscreen system with a dedicated drainage plane might not be as critical as for fully exposed exterior walls. However, installing furring strips behind the cladding to create an air gap is still a good practice. This gap allows for air circulation, which helps manage any incidental moisture and promotes drying, contributing to the longevity of the installation.
How does the Boise climate affect thermally modified wood on a covered patio?
Boise, ID, experiences distinct seasons with hot, dry summers and cold winters. While covered patio walls are protected from direct precipitation, they will still be subject to significant temperature swings and fluctuating humidity. Thermally modified wood's improved dimensional stability helps it resist movement associated with these changes, making it a suitable choice for enduring these environmental conditions. Choosing a finish that can withstand both summer heat and winter cold will be beneficial.
Request a Material Quote for Your Covered Patio Walls
Ready to enhance your Boise, ID covered patio with thermally modified wood? Provide your project dimensions, desired profile, and ZIP code to request a material quote. We can confirm current availability and service options for your project. Explore our selection of thermally modified wood, including NORX and Maximo Accoya, as well as siding and cladding options.
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