Our Timber sash window replacement consists of replacing your old windows with new hardwood or softwood windows into your old box. This is a cheaper option than choosing to change the box . This set of sashes comes fully draughtproofed as standard with a choice of double or single glazing and a choice of colours for your window furniture. This product is offered in both hardwood and softwood.  If your box is severely rotten or severely out of level this may not be an option and you may have to get a new box sash.