What you need to know about Engineered Hardwood Floors

What exactly is engineered hardwood flooring?

This type of floor starts with a bottom core of pressed plywood or manufactured wood layers, and is then topped with a nicer wood veneer; this top "wear layer" is the part that's seen once installed. The invisible bottom layers make natural movement easier, which prevents buckling or warping when temps fluctuate. It also makes it more affordable.
 There are a lot of options and brands out there these days; you have to find the one that has the combination of features you desire.



Engineered Wood Floor Installation

Floating: This is an increasingly popular method of installation, where the boards "float" above the subfloor vs. being affixed. Floating floors are less prone to warping than the glue down method.
Click Lock: This refers to the method of joining the boards together as they are installed over the subfloor. Individual pieces literally lock together in a special tongue and groove system. This makes for easier (and faster) installation, which you should think about if you are doing it yourself, or paying someone by the hour. If it's not a click lock floor, boards might need to be glued to each other first as they are installed.
Underlayment: This is the soft layer, usually foam or plastic, that lies between floating (not glue or nail down) hardwood flooring and the subfloor. Spend a little more on a thicker pad, and you'll reduce noise considerably. Cork is the Ferrari of underlayments.
Glue Down: With this method, the boards are glued directly to the subfloor, most likely concrete. Note that the glue itself can be expensive, so make sure to factor that into your budget. It can also be toxic, so choose carefully and plan for ventilation during installation.
Nail /Staple Down: The floor boards are nailed down to the wood subfloor. It isn't recommended for your average DIYers.



Original Source: Apartment Therapy