Dedicated to the Art of the Sash Window

More than 50 years of combined experience, an unwavering commitment to craftsmanship, and a genuine passion for preserving Britain's architectural heritage.

"We don't just replace windows — we preserve the character and heritage of your home."

Our Story

Who We Are

The Conservation Sash Window Company was founded with a clear purpose: to provide a specialist service for homeowners whose properties demand more than a standard window company can offer. Whether you live in a listed building, a conservation area, or simply a home where quality and aesthetics matter, we bring the same level of care and expertise to every project.

We are based in Harlow, Essex, and serve clients across London, the Home Counties, and beyond. Our team has spent decades working with period properties, understanding not just the technical demands of sash window installation, but the importance of getting every detail right — from the profile of the glazing bar to the smoothness of the sash cords.

We work with listed buildings, Victorian terraces, Georgian townhouses, Edwardian semis, and everything in between. Whatever the age or style of your property, we have the expertise, the materials, and the dedication to deliver outstanding results.

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50+

Years Combined Experience

1,000+

Windows Installed

100%

UK Workshop Crafted

5★

Average Customer Rating

How We Got Here

Our Journey

Gary Baker, the founder of The Conservation Sash Window Company, began his career in the building and construction industry decades ago. Over the years, he developed a particular expertise in period properties and traditional joinery — and a growing frustration with the lack of specialist services available for homeowners in conservation areas and listed buildings.

Too often, he saw beautiful original sash windows ripped out and replaced with inappropriate modern alternatives, or left to rot because owners couldn't find anyone willing to restore them properly. He founded The Conservation Sash Window Company to fill that gap — offering a service built on genuine expertise, quality materials, and real pride in the finished result.

Est.

The Company is Founded

Gary establishes The Conservation Sash Window Company with a focus on listed buildings and conservation areas, bringing decades of building industry experience to a specialist niche.

2010s

Growing Reputation Across London

Word spreads across North and East London as homeowners in conservation areas discover a company that truly understands their needs — one that won't compromise aesthetics for convenience.

2020

CERTASS Approved Installer Status

We achieve CERTASS approved installer status, giving our customers added peace of mind and formal recognition of our commitment to quality and compliance with building regulations.

Today

Serving Clients Nationwide

With an exceptional reputation built on hundreds of five-star reviews, we continue to serve homeowners across London, Essex, Hertfordshire, and beyond — with the same attention to detail we've always had.

What Drives Us

Our Values

Uncompromising Quality

We use only the best hardwoods, the finest double-glazing units, and the most effective draught-exclusion technology. Every window we install is one we're proud to put our name to.

Attention to Detail

From matching your existing window profiles to ensuring the sash cords run perfectly smoothly, we obsess over the details that others overlook. The result is a finish that looks and feels exactly right.

Honest Communication

We give clear, detailed quotes with no hidden costs. We explain exactly what we're doing and why, keep you informed throughout the project, and only start work when you're completely happy.

Respect for Heritage

We understand that your home is more than bricks and mortar. When we work on a period property, we treat its architectural heritage with the same respect we'd want someone to show our own home.

Modern Performance

Traditional aesthetics don't have to mean cold, draughty rooms. Our windows deliver outstanding thermal and acoustic performance while looking exactly as they should in a period property.

Reliability You Can Count On

We turn up when we say we will, complete work within the agreed timeframe, and leave your home clean and tidy. Straightforward professionalism — every time.

The Detail is Everything

Craftsmanship You Can See and Feel

Every sash window we install is a testament to what happens when traditional joinery skills meet modern materials. We don't cut corners, and we don't rush. The weight of the sashes, the smoothness of the cords, the precision of the glazing bars — every element is considered and executed with care.

Our windows are manufactured to our own specification — 33mm double-glazed sashes with a 125mm box width — designed specifically to replicate the slender profiles of original period windows. The result is a window that looks authentic from the street and performs to a modern standard from inside.

Whether we're working in a Grade II listed townhouse in Islington or a Victorian terrace in East London, the standard of finish is exactly the same. We take the same pride in every job, regardless of size or location.

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The People Behind the Work

Meet the Team

Gary Baker

Founder & Director

With decades of experience in the building and construction industry, Gary founded The Conservation Sash Window Company to bring genuine specialist expertise to listed buildings and conservation areas. He personally oversees every project and is always on hand to advise clients.

Richard

Lead Carpenter

An experienced carpenter, Richard carries out the installation and joinery work on our projects. His meticulous approach and deep knowledge of period window construction — including sash pulley mechanisms, beading, and felt sealing — ensures every job is finished to the highest standard.

Tom

Craftsman & Decorator

Tom works alongside Richard on installations, handling finishing, painting, and decoration with the same care and precision as the joinery work itself. His eye for detail ensures the completed windows look as good as they perform — inside and out.

Why Choose Us

What Makes Us Different

We're not a general window company that happens to do sash windows. We're sash window specialists — and that distinction matters enormously when your home is a listed building or sits in a conservation area.

Genuine Specialist Expertise

We understand the specific requirements of conservation officers, listed building consent, and Part L building regulations — so you don't have to.
Unique Window Specifications

Our 33mm double-glazed sashes with 125mm box width are designed specifically to replicate original window profiles while meeting modern thermal standards.
UK Workshop Craftsmanship

Every window is made to order in British workshops — not imported from overseas — ensuring quality control at every stage of manufacture.
Frame Preservation Where Possible

We can often replace the sashes using your existing box frames, preserving original architecture and minimising disruption to your home.
Transparent Pricing

Our quotations are detailed, clearly set out, and free of surprises. What we quote is what you pay.

In Their Words

I am absolutely delighted with the work of Gary and the team. The work was completed on time, on budget and to an exceptionally high standard. They specialise in double glazing period windows in listed buildings and conservation areas and use high spec materials that satisfy even the most stringent conservation area planning regulations — yet their prices compare favourably with other firms.

Andrew — SE4

Trusted & Accredited

Our Accreditations

We hold the certifications and approvals that matter most when working on period and listed properties, giving you complete confidence in our work.

CERTASS Approved Installer

As a CERTASS registered installer, our work is independently certified to meet current building regulations. This means you receive a compliance certificate with every installation — essential for listed buildings and conservation areas.

Approved Craftsman

Our team holds Approved Craftsman accreditation, recognising the skill, training, and professionalism our carpenters bring to every project. It's a mark of quality that sets us apart from general window companies.

Part L Building Regulations

All our double-glazed sash windows comply with Part L building regulations for thermal performance — so you can enjoy the benefits of modern energy efficiency without compromising the character of your property.

Let's Talk

Ready to Transform Your Windows?

Whether you have a specific project in mind or just want to explore your options, we'd love to hear from you. All consultations are free and completely without obligation.

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