Shop our range at Selhurst Timber of cavity closers designed to seal and insulate cavities around windows and door openings in cavity wall construction. These products help prevent cold bridging, improve thermal insulation and protect against damp penetration within the building structure. Used by builders and installers during window and door installation, cavity closers play an important role in improving energy efficiency and ensuring compliance with building regulations. Are you spending over £150? You will receive free local delivery on qualifying orders across our delivery area.