Hardboard, also known as high-density fiberboard (HDF), is a relatively cheap composite wood building material. It’s pretty versatile and can replace wood in many interior design aspects like molding, flooring or cabinets.
The Main Advantages And Disadvantages Of High-Density Fiberboard (Hardboard):
|Hardboard is durable & impact resistant||Hardboard itself is not waterproof|
|Moisture resistant||No natural wood grain aesthetic|
|Relatively low cost compared to plywood||Not as strong as plywood|
In this article, we’ll highlight the pros and cons of HDF as we jump into the details of this building material. We’ll take a look at what it can and can’t be used for, as well as ways to waterproof it.
High-Density Means Hard
What exactly is high-density fiberboard? It’s an engineered, composite wood board. Explaining how it’s manufactured is the most effective way of describing what high-density fiberboard actually is. Essentially, fine wooden fibers are mixed with a resin and then subjected to immense pressure. This compression combined with heat results in a composite wood material with high density.
How high? Typical HDF densities are between 50 and 65 pounds per cubic foot. Take a look at the table below comparing it to other building materials.
|Medium Density Fiberboard||37-50|
This higher density directly equates to a harder surface. So, whatever you’re building will be more impact resistant. A few examples of the benefits are:
- More durable flooring in high-traffic areas
- Sturdy cabinets and drawers
- Molding resistant to dings and scratches from furniture
When considering the typical household uses for hardboard, it is a very durable option. Note that durability should not be confused with strength.
Hardboard Is Not As Strong As Plywood
While the density of hardboard does give it a tough, impact-resistant surface, it is not as structurally capable as plywood or hardwood lumber. The trait that makes wood a strong building material is the fact that its natural fibers are still intact.
All fiberboard products, including high-density fiberboard, lack this trait due to the very nature by which they are manufactured. The wood fibers are so fine before the board is compressed that they are almost a powder, much like sawdust.
When the board is compressed, these individual fibers are held together by resin, not a cellular bond like in natural wood.
This isn’t a bad thing by any means, but it is an important distinction to make. It serves as a reminder that engineered wood like high-density fiberboard is a material designed to be used for more aesthetic purposes in a home. Such as,
- Laminated flooring boards
- Laminated countertops
- Cabinets (painted or laminated)
- Furniture (backing panels)
The structural aspects in construction, like framing and roof decking, should be done with lumber and plywood.
The closest thing to a structural application for hardboard would be subflooring, but even then, it should be laid over plywood or an existing floor.
Moisture Resistant vs. Waterproof
One of the main advantages of a high-density fiberboard is its moisture resistance. This is not to say that HDF is totally waterproof, though. High-density fiberboards are moisture resistant, but not waterproof.
High-Density Fiberboard Won’t Warp
This is what moisture resistance means. A typical issue with wooden boards is that they absorb the ambient moisture, which gives them the tendency to warp and expand.
This can become an issue on humid days. Granted, wood warping can be avoided by properly sealing the wood. However, HDF board is generally more resistant to absorbing moisture from the air.
This is because of its high density. The material is much less porous than normal wood (still porous though!), so there is just literally less space for moisture to occupy in the board.
This is a nice property to have when building cabinet doors or drawer panels, especially for applications in a kitchen where the temperature tends to swing more than anywhere else in the house.
It Will Permanently Bulge Instead
While it’s less porous and less likely to absorb moisture from the air, high-density fiberboard is still plenty porous when we start to talk about water resistance (or lack thereof).
No fiberboard, including HDF, is waterproof. It can be waterproofed, though. This is usually done by laminating the board or tempering it. Painting it will even work to add water resistance.
The problem occurs when that waterproof seal is broken, though. High-density fiberboard will absorb water when exposed to it. But then again, so will regular wood, so what’s the big deal?
Wet HDF Board Won’t Return To Its Original Shape
When normal wood absorbs water, it tends to expand, and maybe warp a little bit. But as it dries, it almost always returns to its original shape. This is not the case for high-density fiberboards.
In fact, there was a class-action lawsuit against a manufacturer of hardboard siding due to the rapid deterioration when exposed to the slightest bit of water.
When a high-density fiberboard absorbs water, it expands, much like wood. But, unlike wood, it does not return to its original shape when it dries.
This leaves permanent bulges in the material that are, quite frankly, eyesores. And in the case of the hardboard siding (no longer used btw), it would cause deterioration.
This can be an issue with an HDF core in laminate flooring as well. Spills can do permanent damage to HDF flooring if they are not cleaned up immediately. Be wary of:
- Slow leaks in kitchen drains
- Leaky housplant pots
- Wet shoes stored on the floor
Then there’s flooding. Hardwood floors at least have a chance of being salvaged after a flood, but the same cannot be said for HDF floors.
So, while several measures can be taken to seal in an HDF core, the HDF itself is not waterproof.
Some ways to waterproof high-density fiberboard are:
- Tempering it with linseed oil
- Painting it
- Laminating it with vinyl
In most cases, one of these methods will have been done before you buy HDF flooring or cabinets.
High-Density Fiberboard Has No Natural Wood Grain
We already discussed the structural impacts of HDF not having a natural wood grain, but how about the aesthetic impact.
Now, beauty is most certainly in the eye of the beholder, but we do feel the need to point out that staining high-density fiberboard is not a finishing option for whatever you’re building.
The material is technically made of wood, yes, but there will be no naturally occurring swirls or patterns that many people appreciate in their cabinets or flooring. The closest you’d be able to come is by laminating a natural wooden veneer.
As a core material, HDF is just fine. In fact, it has the benefit of hardness like we mentioned earlier.
However, if you really appreciate the way natural wood looks, and weigh aesthetics highly in your design criteria, then HDF might not be for you.
It is Cost Friendly
A quick scan of the main home supply stores online proves that high-density fiberboard comes with a lower price tag than plywood. Check out these Home Depot prices.
|3/16 in. x 4 ft. x 8 ft. Hardboard Tempered Panel||$15.90|
|3/8 in. x 4 ft. x 8 ft. BC Sanded Pine Plywood||$34.00|
Can’t argue with half the price! Engineered wood also creates cost-friendly solutions for flooring and cabinets when compared to traditional hardwood options.
If there are only a few things you’ve learned from reading this, let them be these:
- High-density fiberboards are not waterproof. It must be sealed to protect it from water damage
- It is durable, but not quite as structurally capable as regular wood
- It is less costly than wood, but many would say it’s less pretty, too.
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As a homeowner, I am constantly experimenting with making the structure of my house more energy-efficient, eliminating pests, and taking on DIY home improvement projects. Over the past two decades, my family has rehabbed houses and contracted new home builds and I’ve learned a lot along the way. I share my hard-learned lessons so that you can save time and money by not repeating my mistakes.