What Is the Difference Between Solid Hardwood and Engineered Hardwood?

Solid hardwood and engineered hardwood can look almost identical once they're installed, and both can be real wood flooring. The biggest difference is how the boards are constructed and how that construction affects where and how we can install them.

Solid hardwood is pretty much exactly what the name says. Each plank is one solid piece of wood from top to bottom. Engineered hardwood is constructed using multiple layers, with real hardwood making up the finished surface. The National Wood Flooring Association considers both solid and engineered hardwood to be real wood flooring.

One of the biggest advantages of solid hardwood is how much wood we have to work with. A quality solid hardwood floor can be sanded and refinished numerous times throughout its life. If the floor becomes scratched and worn or you simply want to change the stain years down the road, there's usually a good amount of material available to work with.

Engineered hardwood can also be refinished, but this is where you need to pay attention to what you're buying. The thickness of the real wood wear layer varies considerably between products. Some engineered floors have enough material to be sanded and refinished, while others have very thin wear layers that give you much less room to work with. The NWFA actually has a certification program specifically for engineered flooring with wear layers thick enough to be refinished.

So if you're comparing engineered hardwood products, don't just look at the color and price. We'd also want to know how the floor is constructed and how thick that usable wood surface actually is.

Where engineered hardwood has a major advantage is stability. Wood naturally responds to changes in moisture and humidity by expanding and contracting. Because engineered flooring is built in layers, it's generally more dimensionally stable than a solid piece of wood. That's one reason engineered hardwood gives us more options when we're dealing with concrete slabs or below-grade installations.

That's particularly important for homes here in Texas where concrete slab foundations are extremely common. Depending on the particular flooring product, engineered hardwood may be glued to properly prepared concrete or installed using another manufacturer-approved method. Solid hardwood can also be installed over concrete with certain systems, but the installation method and manufacturer requirements become very important. The NWFA says both solid and engineered flooring can be installed over properly prepared concrete when the flooring and adhesive manufacturers allow it.

Neither type of wood automatically wins on appearance either. Engineered hardwood isn't the same thing as laminate or vinyl plank with a picture of wood printed on top. With a true engineered wood floor, the surface you're looking at and walking on is real wood.

So, which one is better?

It really depends on the project.

If we're working with a suitable wood subfloor and you want a floor that can potentially be sanded and refinished numerous times over a very long service life, solid hardwood is hard to beat.

If we're installing over concrete, dealing with below-grade conditions, or need greater dimensional stability, engineered hardwood may make more sense. And if you choose a quality engineered product with a substantial wear layer, you're not necessarily giving up the ability to refinish the floor later.

We wouldn't recommend one simply because somebody told you solid is "better" or engineered is "cheaper." We'd look at your subfloor, moisture conditions, where the floor is being installed, how you want it installed, and what you expect from that floor twenty years from now.

That's really the difference: solid and engineered hardwood can both give you a beautiful real wood floor. The better choice is the one whose construction makes sense for your particular space.

Can Wood Flooring Be Installed Over Concrete?

Yes, wood flooring can be installed over concrete, but this is one of those situations where what happens before the wood goes down can be just as important as the flooring you choose.

Concrete and wood behave very differently. Concrete can contain and transmit moisture, while wood naturally expands and contracts as moisture and humidity change. If we're going to put the two together, we need to make sure the slab and flooring system are actually ready for each other.

The National Wood Flooring Association says both solid and engineered wood can be installed over concrete when the slab is properly prepared and the particular flooring and installation system allow it. The requirements of the flooring and adhesive manufacturers ultimately determine what can be installed and how.

For most concrete-slab projects, engineered hardwood is going to give us more installation options. Engineered wood is constructed in layers, which makes it more dimensionally stable than traditional solid hardwood as conditions change. Depending on the product, it may be glued directly to properly prepared concrete or installed as a floating floor over an approved underlayment. Some manufacturers have very specific limitations, though. For example, Shaw states that its solid hardwood requires a nail-down installation while certain engineered products can be floated over a concrete subfloor.

Before we install anything, one of the biggest things we're concerned about is moisture.

You can't look at a concrete slab and tell how much moisture is in it. You also can't assume an older slab is dry simply because it's been there for 20, 30, or 50 years. The NWFA specifically recommends evaluating old slabs for moisture just like newer slabs and following the flooring and adhesive manufacturer's moisture limits.

That's important because excessive moisture coming through concrete can create serious problems for a wood floor. Depending on the system, that may mean using an approved vapor retarder, moisture-control system, or adhesive designed to provide moisture protection. The solution depends on the moisture readings and the products we're installing.

We also need to look at the condition of the concrete itself.

The slab needs to be sufficiently flat for the flooring being installed. High and low areas may need to be corrected, cracks and damaged areas need to be evaluated, and contaminants such as paint, oil, wax, sealers, or old adhesives may need to be removed. NWFA guidance calls for concrete used beneath wood flooring to be dry, flat, and free from contaminants and problematic loose or hollow areas.

This is where our experience working with concrete becomes particularly useful. Sometimes the best thing we can do for a wood floor has nothing to do with the wood itself. It's correcting the concrete underneath it before we ever open the first box of flooring.

So, can wood flooring be installed over concrete?

Absolutely.

But we wouldn't recommend simply buying hardwood and gluing it to a slab because somebody says the product can be installed over concrete. We want to know what kind of wood we're working with, what installation method the manufacturer allows, how flat the slab is, what condition it's in, and most importantly, what the moisture conditions look like.

If those things check out and the correct flooring system is selected, there's no reason a concrete slab can't be the foundation for a beautiful wood floor.

Can Hardwood Floors Be Refinished Instead of Replaced?

Yes, and that's actually one of the biggest advantages of having a real wood floor.

If your hardwood is scratched, worn, faded, or you simply don't like the color anymore, you may not need to tear the entire floor out. Depending on the type and condition of the wood, we may be able to sand the existing surface down and refinish it instead.

But before we start sanding anything, we need to figure out exactly what kind of wood floor you have and how much usable wood is left.

Solid hardwood gives us the most flexibility. A typical solid hardwood plank is made from one piece of wood and is often around 3/4-inch thick. Because there's substantially more usable wood above the tongue-and-groove portion of the plank, many solid hardwood floors can be sanded and refinished multiple times during their life.

Engineered hardwood is where we have to be more careful.

Engineered hardwood is still real wood, but instead of the entire plank being one solid piece, it has a real hardwood wear layer over an engineered core. How thick that top layer is determines whether we can safely sand the floor. Some engineered floors have a thick enough wear layer to be refinished, while others may have such a thin veneer that aggressive sanding could go straight through the hardwood surface.

That's why we wouldn't look at an engineered floor and automatically tell you we can refinish it. We'd want to identify the flooring and determine how much usable wear layer remains first.

There's also a difference between refinishing and recoating a wood floor.

If the damage is mostly light surface wear, minor scratches, or a worn finish, the floor may only need to be cleaned, properly prepared, and recoated with a new protective finish. A full refinish is more involved and normally means sanding away the existing finish and a small amount of wood before applying the new stain and finish.

Then there are situations where refinishing isn't going to solve the real problem.

If the wood has severe water damage, significant warping or cupping, rotten areas, structural problems underneath it, or boards that are damaged beyond what sanding can correct, those areas may need to be repaired or replaced. Sometimes we can replace individual damaged boards rather than tearing out an otherwise good floor.

That's another reason we like wood flooring. Scratches and wear don't necessarily mean you've reached the end of the floor's life.

With some other flooring products, once the finished surface is worn out, replacement is your main option. A good hardwood floor can potentially be restored, recolored, and refinished multiple times depending on its construction and remaining thickness.

So, can your hardwood floors be refinished instead of replaced?

In many cases, absolutely.

Before spending the money to tear out a real wood floor, we'd rather inspect what you already have. If there's enough good wood left to work with and the underlying floor is still in good condition, refinishing it may give you the look of a new floor without throwing away a perfectly good one