Used filler at installation

Q: I had 6 inch knotted pine installed on a sub-floor in my new home. Is there any excuse for wood filler to be used to fill gaps in my floors up to 1/8 wide, other than faulty installation, or boards that were not planed before installation? I am being told it is because of moisture and expansion and contraction.

My problem is, if they used filler at installation to cover these gaps, then the boards were never seated in the first place. Am I wrong? I am also being told that gaps the width of a nickel are normal. Is this rule of thumb true on brand new floor installations as well?

A: I think if your gaps are only 1/8 wide with pine, then you are doing quite well. I have yet to see a pine floor that didn’t develop gaps. I would lean to the view not to fill them if the gaps are that small. If any flooring is delivered and acclimated to a house, then installed, and it gets some cracks – what else can be done?

Follow-up Q: I really really appreciate you taking time for my questions. So just for clarity on my part. Gaps that were incorporated into a new floor installation (not developed over a period of time) are normal and not a part of a faulty installation?

I will be honest with you, I about blew my lid when I told my builder that I can’t even sweep my floors because all I am doing is pushing dirt into the gaps of my floor. His response was ” Well, use a vacuum instead.”

A: I must have misunderstood your initial email. I don’t think gaps “incorporated” into a new installation, which did not happen over time is necessarily considered normal. If the boards were poorly milled with mismatched widths, I think you should have been made aware of it right away. Unless you bought this product at a low cost, knowing the fit was poor.

Pine does tend to shrink over time and I don’t know that there is much to be done about it, except to make sure it is properly dried and acclimated to the environment it will be installed in, and that environment is maintained year round.