Selecting the Best Finish for Interior Wooden Doors
Over the last decade or so the concealed material composition and construction details of interior architectural wood doors have undergone significant changes. Solid wood, once the only option for door construction, is often replaced by MDF, agrifiber, fire resistant composite, honeycomb or expandable paper core. These new engineered wood products are beneficial in terms of cost reductions, improved production efficiency, and enabling manufacturers to provide better doors.
However, when it comes to the visible face of an interior door, we generally still want to have a high-quality transparent wood finish. Attributes such as color and light and dark values are an important part of a door face’s overall appearance, but it’s the grain and veneer characteristics which are often the most important features of transparently finished wooden doors.
Installing Interior Wood Doors
It’s becoming increasingly less common for a commercial project’s woodwork subcontractor to provide and/or install interior wood doors.
When it does happen, a woodworking firm could opt to fabricate the doors in-house if only a small number is required or when the doors come within a blueprint matched area of decorative wall paneling. If this is the case, the woodworker might prefer total control of the veneer matching and sequencing as it transitions from the panels to the doors, rather than coordinating this intricate task with a third party door manufacturer.
There is also the option of outsourcing door work to a custom lay-up company or a door manufacturer (just don’t forget that it’s your responsibility as the woodwork subcontractor to ensure your end product conforms with the AWI Standards).
Finishing Products for Interior Wooden Doors
The finish you choose depends on how well you need to protect the surface, how well the finish will hold up, how easy it is to apply, and how you want it to look.
Finishing products fall under different categories according to how they work and the protection they offer. These categories include wax, oil, shellac, varnish, lacquer, and water-based finishes.
The characteristics of different finishes vary by degrees, but always include:
- Some form of protection
- Ease of application
There isn’t, sadly, one single finish that comes top in all of these characteristics, so you must choose a finish that’s the most appropriate for your project and accept some compromise. For example, both oil and wax finishes are easy to apply and leave wood looking rich and natural – but neither is very durable.
Durable Finishes for Interior Wood Doors
Durability is often the key criteria when it comes to selecting the best finish for interior wood doors, especially on a commercial project. Durability is measured by a finish’s resistance to water, chemicals, solvents, scratches, and heat. Wax, shellac, and lacquer finishes can become damaged if they are exposed to water, and these finishes also scratch easily. Of all the finishes, a chemically cured finish such as catalyzed lacquer, urethane or conversion varnish are usually your best options for overall durability.
AWS Specifications for Interior Wooden Door Finishes
Within the Architectural Woodwork Standards there are specifications for interior wood door finishes which take the panel face veneer standards of the Hardwood Plywood & Veneer Association as the minimum standard.
If you are specifying interior wood doors for a QCP-certified project, you need to determine:
- Veneers for transparent finishes – numerous foreign and domestic wood species are available and many different visual effects can be obtained by face veneer matching. You should specify the:
- Appearance and layout of individual pieces of veneer
- Matching between pieces (leaves) of veneer
- Appearance of doors in pairs or sets
- Appearance of doors with transoms
- Materials for opaque finishes – choose from medium density overlay, MDF, hardboard, or close grain hardwood.
- High-pressure decorative laminates (HPDL) – almost any high-pressure decorative laminate color and texture can be used in the manufacture of architectural doors.
If you are making internal doors according to the specifications set out in the Architectural Woodwork Standards, it’s important to reference different sections of the Standards in order to ensure you are adhering to all the guidelines. While Section 9 provides a specific overview of doors, you should also reference the updated AWI-300 section which covers materials.
You’ll find more information and guidance on internal wooden doors in the AWI 0620 – Finish Carpentry/Installation, Section 9. This section covers interior doors in detail, as well as compliance requirements.
Contact us to find out more about how to join the Architectural Woodwork Institute’s Quality Certification Program and strengthen your reputation for quality and integrity.