Technology Improves Durability of Hardwood Floors

While most solid and engineered plank and strip wood flooring products perform predictably, they do have limitations. For instance, traditional wood flooring formats struggle with specific performance attributes, such as resistance to impact, significant static load and maintaining dimensional stability in high or low relative humidity environments. These limitations have historically restricted the environments where wood flooring could be installed, paving the way for other flooring products like vinyl-based sheet goods, luxury vinyl tile and plank, ceramic tile and rigid vinyl (SPC).

Over the years, wood flooring manufacturers have demonstrated remarkable ingenuity in developing products with features to address known issues. Some manufacturers attacked low-hanging fruit — the most easily achievable improvements — by replacing plywood cores with alternative wood and non-wood-based composite materials to enhance hardness and stability. In contrast, others have implemented chemical and physical modifications to the wood (lumber or decorative wood veneer) to achieve comparable performance improvements. This innovative approach has led to the formation and development of niche markets focused on these unique products showcasing enhanced capabilities.

Thermal treatments have been applied to wood for decades to improve its resistance to dimensional changes in extreme environments and to fungal degradation. Scandinavian technologies fine-tuned thermal wood modification, specifically with external applications in mind (decking, siding and fascia). The thermal treatment process alters specific chemical components in the wood’s cell wall, limiting its use mainly to non-structural elements. While thermal treatment enhances dimensional stability, it also degrades some of the physical properties of wood. Some engineered wood flooring manufacturers in the United States, Europe and China experimented with thermally treated face veneers, hoping to mitigate dimensional issues while enhancing aesthetics. These producers soon found heat-modified veneers were too soft for long-term flooring performance, suffering from significant indentation and surface gouging with minimal use.

More commercially successful methods have been developed to enhance physical performance. Some proprietary techniques involve filling voids in wood with various polymers cured under pressure and heat, resulting in a high-density product resistant to indentation from static and dynamic forces, making it suitable for light commercial applications. This technology typically does not substantially change the wood’s dimensional properties because it does not alter the wood cell walls. Other chemical treatments have been developed to treat wood by spraying, dipping or coating. These chemicals carry specific resin and wax packages into the wood’s cellular structure and occupy or block the water-bonding sites in the wood cell walls, making it difficult for water to be chemically bonded, enhancing dimensional stability and improving physical characteristics.

Many proprietary methods have been created to increase wood’s hardness and dimensional stability. Controlled compression of heated and plasticized wood significantly boosts its resistance to indentation. The heating process occurs at lower temperatures than traditional thermal treatments used on wood for outdoor applications. In addition to heating the wood, some processes pre-treat the wood with a caustic solution to soften it and help the wood deform when pressurized. Applying pressure to the heated wood reduces the void space, increasing density and enhancing indent resistance. These processes aim to compress and deform the wood cell walls without fracturing or crushing the wood cells. While the treatment methods are intricate and can make product manufacturing more costly, they offer performance benefits that enable effective use in environments unsuitable for traditional wood flooring.

The aesthetic preferences of designers, architects and consumers have led to the development of new product categories. Several companies have specialized in producing wide plank (12 inches or more) and long plank (12-foot-plus) engineered wood products to satisfy the rising demand for large-format planks. Designing, manufacturing and installing these wide, long-format engineered wood flooring products requires careful consideration, as they may exhibit cupping and crowning more noticeably if not properly fabricated, stored or utilized. Internal stress from fluctuating environmental conditions can lead to cracking in the face veneer of wide planks before and after installation.

Besides wide and long planks, reclaimed wood continues to gain popularity. It boasts an impressive reuse narrative and a rustic aesthetic that appeals to many designers and consumers. However, using reclaimed lumber presents challenges; manufacturers must ensure it is properly dried and sterilized to eliminate beetle larvae. Some reclaimed wood may also contain contaminants, such as heavy metals from lead-based paints and other chemicals.

End grain flooring has been a staple in commercial and residential settings for more than a century. Known for its inherent toughness and resistance to indentation, it offers unique visuals in various formats, including squares, rectangles and other polygons. However, solid end grain flooring reacts differently to moisture than a solid wood plank. Depending on the shape of the end grain block, dimensional movement potential requires the material to be well-acclimated to the installation environment before actual installation. This product may also require some non-standard practices for spacing and installation.

When dealing with these unique wood flooring products, pay attention to the manufacturer’s installation and maintenance guidelines. Adhering to these guidelines is key to ensuring the long-term performance of the product and installation system.

Brian Beakler is owner of Beakler Consulting Services and president of the Floor Covering Institute. He holds a PhD in forest resources production and management from Pennsylvania State University.