Here at Sash Windows, we like to know we are being the best business possible. That’s why we have many accreditations to our name that we hold dear. These companies help us maintain a high service standard for all our customers. Below, we have listed our accreditations with explanations of their meaning so you can also explore them. Trust us, they have all given us exceptional service and are helping us to do the same for our customers.
Checkatrade
Founded in 1998 to eliminate rogue traders, Checkatrade conducts strict background checks before allowing businesses to join, and requires members to publish verified customer feedback. Sash Windows London has been a Checkatrade member since 2012 and currently holds an impressive overall rating of 9.88 out of 10, based on over 700 reviews. This reflects our commitment to quality, reliability, and excellent customer service in the supply and installation of sash windows and doors.
British Safety Council
As a member of the British Safety Council, Sash Windows London is committed to maintaining the highest health and safety standards in every project we undertake. In 2025, the British Safety Council remains a trusted authority dedicated to improving workplace safety and well-being across all industries, including construction and home improvement. With over six decades of experience, the British Safety Council supports organisations like ours by providing essential training, guidance, and best practices to ensure our team works safely and efficiently. Their focus on preventing injuries and promoting well-being aligns perfectly with our promise to deliver quality sash window installations and a safe working environment for our staff and customers. Being part of this respected organisation reflects our ongoing dedication to professionalism, reliability, and the well-being of everyone involved in our projects. At Sash Windows London, excellent safety standards are fundamental to outstanding craftsmanship and customer satisfaction.
FENSA
FENSA stands for the Fenestration Self-Assessment Scheme. The work must comply with current thermal performance and Building Regulation standards whenever windows or doors are installed or replaced. A certificate from a Competent Person scheme, such as FENSA, is required to confirm this compliance. FENSA enables companies specialising in window and door replacements to self-certify that their work meets Building Regulations, eliminating the need for a separate inspection by Building Control. It is one of the UK’s most trusted and successful Competent Person schemes for this type of work. At Sash Windows London, we are proud to be registered with FENSA, as we know firsthand that it ensures high standards, reliability, and peace of mind for our customers.
The Wood Window Alliance
Sash Windows London is proud to be a member, promoting the highest standards for timber windows and doors. The WWA legally sources timber from sustainably managed forests, ensuring customers receive some of the most environmentally friendly products. Not all timber windows and doors are made to the same standards, which is why the Wood Window Alliance was established—to set a benchmark for quality, performance, and sustainability. As a member, Sash Windows London adheres to these strict criteria, offering timber windows and doors independently verified for their craftsmanship, durability, and energy efficiency. The company’s affiliation with the WWA demonstrates its commitment to providing advanced, energy-efficient products built to last and responsibly sourced. When you choose Wood Window Alliance timber through Sash Windows London, you can be confident that your purchase meets the highest quality and environmental standards in the UK market.
Constructionline
As a registered member of Constructionline, Sash Windows London leverages one of the UK’s leading pre-qualification systems to connect with buyers and suppliers. Constructionline simplifies contracting from start to finish—helping customers optimise performance, minimise risk, and seize new opportunities. All of Constructionline’s services are designed to support day-to-day operations through a network of carefully selected partners, maximising value for everyone involved.
Trustpilot
Trustpilot is an online review platform founded in Denmark in 2007. It publishes independent feedback to help people buy confidently, believing that by sharing experiences, we build trust and transparency, enabling companies to harness the power of customer reviews. As of May 2025, Sash Windows London maintains an excellent Trustpilot presence, holding a 4.8 out of 5-star rating based on over 180 verified reviews. Customers consistently praise our craftsmanship, professionalism, and clear communication, highlighting on-time installations and meticulous clean-up, while only a handful mention extended lead times on bespoke orders. You can read these honest ratings and comments on our Trustpilot page, where each review reflects our commitment to quality, reliability, and outstanding customer service.
