I installed 8” plank, 1/2” thick engineered hardwood in our master bedroom. Glue down on slab. We had planned on doing the whole house w/ the same wood but didn’t really have a place to store it for several months while we finished some other projects. Long story short, I found out the product was discontinued so purchased the rest of what we needed. It must be a different batch because the longer boards (up to 7’) are severely “banana’d”. It gets worse the longer the board, the longest boards 1” or more. So far I’ve installed about 250 sq. ft. from the new batch. It was extremely frustrating, to say the least! Any tips on how to deal with this? Unfortunately, it’s been too long to return so have to make it work. Considering going to a nail down but would like to avoid the varied floor heights.

Thanks!

A strap type clamp will hold the boards until the glue sets. You ought to get enough clamps to space them at least five feet apart along the edge. If the boards aren't straight you will need to clamp all the rows together every 3 feet or so.
The more clamps you have the easier it is to get the job done.

Thanks for the reply but maybe I used the wrong term. When I lay the boards flat, the middle of the board is close to 1” higher (worst case). It sounds like the straps would be for a bowed board. Do I have my terms mixed up?

One option I ran across in the archives is to kerf the boards to make them more flexible? I’m really just hoping for a way to speed things up. Trying to lay those long boards pushes the glue up and around the edges so I’m constantly having to clean up. It also takes quite a bit of force to set them and I ended up damaging several boards.

Kerfing the back of the boards will allow them to lay flat. Use a circular saw set to the depth of the top part of the tongue from the bottom. Place face down and cut across the board every inch where the board is not flat. It will be much more flexible and set down into the glue with no loss of strength.

Thanks for the reply.