are the UK's leading specialists in sash window & heritage window restoration, timber window repair, draught proofing and conservation upgrades for listed and period properties. With over 40 years of expertise, we combine traditional craftsmanship with innovative technology to improve energy efficiency, reduce noise and extend the life of original timber windows and doors while preserving their historic character. From Grade I and Grade II listed buildings to cottages and country houses, Ventrolla is trusted by listed property owners, conservation professionals and homeowners across the UK to restore, repair and protect Britain's architectural heritage.