Engineered hardwood is available with three basic types of construction: 1) plywood core; 2) 3-ply core, and; 3) HDF core.
Very quickly, plywood core is constructed by gluing and compressing thin layers of wood together in a criss-cross pattern. 3-ply core uses strips of solid wood glued to a backing board with the veneer glued over that. These two types are what have traditionally been used to manufacture engineered hardwood. However, there is a newer option – HDF core.
Plywood Core 3-Ply Core
HDF, or High Density Fibreboard
This is made from recycled wood – damaged or substandard pieces of plywood ground into sawdust, mixed with resin and compressed at high temperature. This construction gives it a couple advantages over traditional core construction:
- It is less susceptible to moisture, making it more stable over time. As humidity levels fluctuate with the passing of seasons, a floor constructed on an HDF core will expand/contract less than its plywood and 3-ply counterparts.
- It is harder as measured by the Janka hardness scale. Most plywood and 3-ply cores are constructed of either poplar or birch. While considered hardwood, they are relatively quite soft. Poplar has a Janka hardness of 700, and birch is 1200. However, HDF has a hardness of 1700. This makes it incredibly dent-resistant.
How HDF will react in a flood
No hardwood flooring type is completely waterproof, and both plywood and HDF will swell. The HDF will not absorb as much water as plywood, however, there is a higher chance that the plywood will dry out and shrink back to its original size. In most cases of flooding, however, either floor will have a to be replaced. Home owner’s insurance will probably cover the cost of replacing any damaged flooring.
Given the advantages offered by HDF core, it is definitely something that you should look at. In the past, any flooring made with HDF was considered a “poor cousin” of the real thing, but advances in manufacturing and technology mean that is no longer the case.