In architectural woodworking, interior wood wall cladding can make or break a project. From veneer matching and choice of material to precise engineering parameters, there is a long list of considerations that must be made in the fabrication and installation of decorative wood wall cladding. In fact, ensuring that veneer panels are matched seamlessly is one of the most complex tasks in architectural woodwork, and getting it right is a do-or-die initiative.
This is why specifications for interior wood wall cladding is an integral part of the AWI Standards, and why QCP projects must be inspected against them. There are few things more frustrating to a woodworker than having to fix an error in sequence-matched veneer panels, and even if they succeed, the process can be costly and time-consuming.
Continue reading to learn the top seven things inspectors look for when carrying out woodwork inspections on wall cladding, so that you can get it right the first time around.
What is Interior Wood Wall Cladding?
Also referred to as wall paneling, wood wall cladding comprises a series of decorative panel designs that breathe life into both residential and commercial spaces. From shiplap and board and batten to flat panel and beadboard, there are many different types of wood wall cladding that architects and woodworkers alike use to elevate the aesthetic of interior space.
Interior wood wall cladding should be fabricated from a range of high-quality materials to ensure maximum durability. Installing wood panels also brings a number of benefits to an architectural woodwork project besides an enhanced design:
- If installed correctly, they’ll stand the test of time without requiring much maintenance
- They improve the functionality of a room by adding thermal and acoustic insulation
- They can help disguise cracks, dents, or cables on the walls
- Their insulative properties make spaces more energy-efficient, and if they’re fabricated from renewable resources, they’re an eco-friendly option
But for everything that can go right with interior wood wall cladding, there are a lot of things that can go wrong. From selecting and matching veneers to using precise measurements and applying wood finishing systems, there are a number of complexities involved in the art of wood wall cladding.
To ensure the paneling work in an architectural woodwork or QCP project meets the AWI Standards, inspectors conduct thorough woodwork inspections. Complying with the standards will help you prepare for the complexities of wood wall cladding.
7 Things Inspectors Look for in Wood Wall Cladding
During woodwork inspections of interior wood wall cladding, QCP inspectors will look at a number of areas to ensure they comply with the specifications of the AWI Standards. All inspections should be viewed under the same lighting that the woodwork will normally be viewed under.
With all that in mind, here are the top seven things inspectors look for in wood wall cladding:
1. Shop Drawings
Shop drawings are integral to architectural woodwork because they’re what enable the designs to be turned into reality. Shop drawings for interior wood wall cladding should be very technically detailed, covering everything from the exact materials and directions of wood grain to wall paneling construction methods, attachment specifications, and precise dimensions.
For QCP projects, any variation from the Specifications and/or Standards require evidence that the design professional has specifically agreed to and initialed any change, or if the woodworker has an approved Permission to Modify. Some of the most common non-conformities inspectors will look for including an incomplete material list, failure to provide finishing requirements or a reference plan, and insufficient construction detail.
2. Panel Sequencing
When inspecting a project’s interior wood wall cladding, inspectors will also review whether it complies with the Project Specifications or AWI Standards specifications on panel sequencing, including for pre-manufactured and made-to-order wall panels.
For example, full-width pre-manufactured sequenced sets should be composed of a specific number of panels that have been sequenced and numbered on a per room basis. Meanwhile, made-to-order sequenced sets must be specified in the documents, and have balance or balance and center matched panels that have been specifically manufactured to exact sizes, according to the project’s net footage and height requirements.
In general, there are two types of panel sequencing:
- Running match: This has a non-symmetrical appearance, given that each panel face is made from as many veneer leaves as needed, which often results in some being of unequal width – but it’s usually the most economical method of sequencing
- Balance match: Veneer leaves used for each panel face must all be the same width before edge trimming occurs. The number of leaves in each panel can either be even (balance and center matched) or odd (balance matched) and this can change from panel to panel
3. Veneer Matching
Veneer matching is a crucial part of woodwork inspections for wall cladding. This is because wall panels that match in terms of color and grain have a huge impact on the overall aesthetic and quality of a project.
While the AWI Standards provide a range of veneer match defaults to guide woodworkers, these won’t always fit the client’s vision, and problems like cost issues or lost projects can arise if the woodworker is unaware of the various matching techniques. Going back to the shop drawings, this is why it’s important to clearly show the matching sequence in those documents so that everyone is on the same page.
There are two main types of veneer matching:
- Sequence wood veneer matching, where panels have a uniform height and width and are manufactured in sequence to ensure that every adjacent panel is compatible in terms of color and grain
- End-to-end wood veneer matching, where panels are first matched end-to-end and then side-by-side so that there is continuation both vertically and horizontally. Leaves can be book-matched or slip-matched. Because this isn’t a default matching technique, it must be specified by the design professional in the shop drawings
4. Species, Slicing, and Matching
Inspectors also look out for the species, slicing, and matching of individual leaves used in wood wall cladding.
Here are a few things to keep in mind:
- Make sure you choose the right species for the project requirements, and that the fabrication, installation, and finishing of the woodwork upholds the integrity of that species
- Slicing methods include either rotary, plain, or quarter sliced. In the case of Oak, rift sliced is also used
- Leaves must either be book-matched, which is best for plain sliced, slip matched, which is best for quartered and rift sliced, or random matched, which is best when trying to achieve a rustic aesthetic
- Matching must be maintained on each panel face, whether that’s running match, balance match, or balance and center match
5. Veneer Flitch Selection
Flitches are logs that have been sliced into leaves, dried, and reassembled. There are four key things you should consider when selecting veneer flitches for wood wall cladding:
- Is the length adequate for the project requirements? Remember: the flitch must be at least 6” longer than the panel requirements
- What will be the net yield for each flitch’s width? The width of individual leaves will change during the slicing process, so it’s important to account for this
- What is the gross square footage of veneer required? This is determined based on the net square footage required times three (which is the average ratio of yield. Some species require a higher multiplier.)
- Is there color and grain compatibility? While exact matching is not possible when selecting multiple flitches, Your flitch selection should be made based on near-exact compatibility in terms of color and grain in order to achieve visual continuity
Another thing inspectors will look for in interior wood wall cladding is the smoothness of flat and molded surfaces. For surfaces that have been machine planed or molded, the smoothness can be assessed using knife cuts. In a nutshell, surfaces are smoother when there are more knife cuts per inch because it means the ridges are closer.
Surfaces can also be sanded to improve smoothness. We recommend using fine-grit sandpaper to minimize striations on the surface, which are easily caused by coarse grits.
The skill of installation is crucial to a project and is a key criterion in woodwork inspections. For wood wall cladding, the installation should involve the use of interlocking wood cleats or metal hanging clips, as well as accurate furring and shimming in order to minimize as much as possible how much face fastening is exposed. In addition, it is important to understand wood movement and the requirements for expansion joints in a run of panels. You can’t stop the panels from expanding and shrinking with temperature and humidity variation. Therefore, you must plan for this movement in your installation.
In addition to all this, inspectors will also review the following areas of interior wood wall cladding as they pertain to Project Specifications and the AWI Standards for wall paneling:
- Variations in natural wood products (Veneer Face Grade Requirements)
- High-Pressure Decorative Laminates (HPDL)
- Fire-rated materials
- Finishing (including the application of sealer on the panel backs)
By knowing what inspectors look for in interior wood wall cladding, you will be able to deliver consistently high-quality paneling work every time, and avoid the common pitfalls in architectural woodwork inspections.