Interior varnishes form a tough hardwearing surface coating. Quality varnishes are considered to be products of low hazard and are therefore safe to use where children play.
Waxes interfere with the adhesion of new varnish.
Remove it with a paint or varnish stripper. To lighten the colour, all previous coatings must be removed. Only a darker colour may be achieved by overcoating. Due to the amount of wear and tear a wooden floor is subjected to, it is necessary to use a floor varnish. Yacht and Outdoor Varnishes are soft as they need to flex with the wood to cope with weather extremes.