Solid Wood or Engineered Wood
If you've never bought a real wood floor before you may well be thinking “solid wood must be the best” and when I started selling wooden floors about 18 years ago I thought the same. However experience soon taught me that for many reasons an engineered wooden floor was the best option for most people, in fact I've owned three properties since then and the only house I put a solid wood floor into was my first one; since then I've always chosen engineered. So you may be thinking why and in as few words as possible I will explain.
Any reputable wood floor brand will produce their flooring with a tongue and groove profile or a click system profile. Either way the only useable part of any wooden floor is what we call the wear layer and this is the section of wood above the top of the tongue. Essentially it is the usable piece of the wood floor and when we say usable we are referring to the fact that most of us want to know that if the floor gets damaged we could sand it down and re-finish it if required. With a 15mm engineered oak floor the typical thickness of oak above the tongue is circa 4mm and if you were to look at a 15mm solid oak floor the amount of oak above the top of the tongue would also be circa 4mm, maybe slightly more but not much. So essentially there is very little benefit in terms of oak wear layer by choosing a solid but this is really only just a small reason to choose an engineered when you consider what I am about to explain further.
A solid oak floor is far more likely to expand or contract when subjected to changes in the surrounding atmosphere. In the winter months we close the doors and turn the heating on which dries the air out and the relative humidity of the air reduces, this in turn means that your wood floor will lose moisture and as the moisture content of the floor drops it will start to shrink and you can expect gaps between boards. There are ways to counteract this with humidifiers but it's not a solution many of us want to accept. Conversely in the summer we open doors, switch off the heating and the sun draws moisture from the ground. This creates a higher relative humidity which enters our homes through the open doors and windows and the wooden floor starts to absorb moisture and expand, if the floor absorbs too much moisture the expansion will be too great and the floor could start to lift. Most of this can be avoided with a good quality engineered floor.
With an engineered oak floor the section of oak is at least one third of the thickness compared to a solid oak floor in the same dimension and for this example we will talk about a 4mm layer of oak. Cutting it to 4mm immediately reduces the tension strength of the oak which does not mean it is weaker in terms of hardness or durability but simply it has less tension strength. This thinner section of oak is then bonded to a substrate such as plywood and I want to explain a bit about plywood. Essentially plywood is several veneers of wood bonded together under high pressure with a very strong adhesive and thus creating a stable sandwich structure with each layer glued at ninety degrees to the adjacent layer. A good quality plywood will be made from birch and be WBP (water boiled proof). This means that if you put the plywood into boiling water for a few hours it will not break down or delaminate. When you bond the 4mm layer of oak to the plywood you create a very stable board which when installed correctly will cope with normal fluctuations in relative humidity.
Another benefit with a quality engineered board is that most of them are suitable for installation over underfloor heating and whilst there may be a few manufacturers of solid wood who say their floors can be installed over underfloor heating. I would encourage you to read the small print and understand the implications of doing this because I believe you will soon start to read that you should expect movement in the floor through the year and movement often brings squeaks and gaps which most of us don't want to see in the floor.
However there's something more to understand in all this. Wood floors have developed massively in the 18 or so years I have been involved with them and the technology and research has brought many benefits. Mills around the world have invested huge amounts or resource into developing unique finishes such as hand scraping, band sawing, UV cured hard wax oils, smoking, weathered, burnt and many other processes to create special colours and textures which can only be achieved in a controlled factory environment. Some of these finishes are simply beautiful and others are extremely hard wearing, either way if you were to sand the floor down you would lose the finish. Also with an engineered board you can have a much wider plank and still have a stable product, this means that most of the special finishes you see on the market today will be on an engineered floor.
Finally there are two main reasons why a wood floor will look tired or worn out. Number one is simply a massive footfall without good care and maintenance and this is simply user error. A correctly maintained floor will last for many years providing the right finish is chosen in the first instance and the correct maintenance procedure is put in place. The second reason is because the floor has moved after installation and is no longer flat, thus creating high spots which are being walked on more than the rest of the floor and the floor is wearing irregularly. This is something which rarely happens with an engineered floor because they are more stable and hence they stay flat and stay looking great.
I hope this helps any readers and researchers to make a calculated choice when choosing to invest in a wooden floor.