Gaps in floorboards

Lawrence,

By far the easiest solution is to throw a rug over the top of them in the cold weather!

I am assuming that the gaps at worst range from zero to a few mm, and can close up to almost nothing in wet periods?

Simplest solution is to run ordinary old brown packaging tape (or mech vent duct tape) to the underside of the floor (also assuming you have access). In time the gaps will accumulate dust, when you next finish the floor - either with a polyurethane or a more "natural" finish, the finishing product will mix with the dust and form a sort of expansion caulking that looks as though it was meant to be there, and the tape will prevent it falling when more movement occurs.

You could get all keen and brush in some wood flour in the first instance I guess, but I wouldn't bother unless I was refinishng the floor.

"I may not be cheap, but at least I'm rough."

Cheers,

P

if the gaps are wide marine decking cauk could be a go.
In the area I grew up in the houses were italian prefab with plain pine floor boards (no T&G) a family down the road filled the gaps with black decking cauk, sanded & clear varnished. Looked quite smart.