Enhancing Home Elegance
for More Than 35 Years
Down to the Last Detail
Get a Personalised Quote
Wooden Windows & Doors for Britain’s Heritage Homes.
Sliding Sash Windows
Our sash design allows for the slimmest frames while accommodating heritage double glazed units – Delivering on performance without compromising on traditional proportions.
For a truly authentic look whilst maintaining the character of your original period property, we offer two specialist services:
Sash Replacement – into fully restored original box frames, retaining the historic features essential for listed buildings and conservation areas.
Complete New Box Frames – where original sashes are beyond repair, we manufacture and install entirely new frames, carefully designed to meet conservation standards whilst replicating the traditional look.
Casement Sash Windows
Our casement windows are not limited in design – we can replicate exactly any original period detail while discreetly incorporating heritage double glazing or other thermally efficient glass options.
To suit a range of period properties and conservation requirements, we offer two specialist services:
Casement Sash Replacement – new sashes fitted into original restored frames, preserving the historic detailing and maintaining of listed and character homes.
Complete New Casement Frames – where the originals are beyond repair or simply prefer a complete new installation. We can manufacture and install complete new timber frames, crafted to meet conservation guidelines.
Front Doors & Rear Doors/ French Doors
Our sash design allows for the slimmest frames while accommodating heritage double glazed units – Delivering on performance without compromising on traditional proportions.
For a truly authentic look whilst maintaining the character of your original period property, we offer two specialist services:
Sash Replacement – into fully restored original box frames, retaining the historic features essential for listed buildings and conservation areas.
Complete New Box Frames – where original sashes are beyond repair, we manufacture and install entirely new frames, carefully designed to meet conservation standards whilst replicating the traditional look.
Who We Are
Landmark Windows Co Ltd is a trusted, family-run business led by Steve and his sons, Tom and Ben, supported by a dedicated team of skilled joiners and craftspeople. With over 35 years of experience, Steve has become a recognised authority in the timber sash window sector — known for his deep understanding of traditional joinery and his unwavering commitment to quality and heritage.
Our reputation has been carefully built on delivering high-performance joinery that respects architectural history while embracing modern standards. From Georgian townhouses to Victorian terraces, we have become a go-to name for enhancing period homes and preserving the character of listed properties throughout London and beyond.
As conservation areas continue to grow across London, our work plays a key role in safeguarding England's architectural heritage. We specialise in designing and manufacturing timber windows and doors that meet the exacting demands of listed building consent and conservation officers — always replicating original features with accuracy, care, and craftsmanship.
All our joinery is made in-house – from manufacturing to full factory spray finishing, including a wide range of glass and glazing options. Ensuring complete control over quality at every stage of the process, guaranteeing a seamless service from workshop to completion.
Supplying Trade
Positioned on the outskirts of London, between Essex and Hertfordshire, Landmark Windows Co Ltd has built a reputation among trade professionals for delivering exceptional quality timber sash windows and doors — reliably, efficiently, and consistently.
As a dedicated manufacturing workshop, we work exclusively with timber and support businesses across the trade who specialise in servicing, maintaining, and upgrading period and listed properties.
Our trade partners are at the front line — trusted by homeowners to protect, restore, and improve some of Britain's most treasured buildings. We support them with joinery that not only meets the technical and aesthetic demands of heritage work but also reinforces their reputation for quality, reliability, and expert care. From bespoke solutions to repeatable project specific windows, we help you deliver lasting results for your clients.
We value long-term relationships, not just transactions. Our team is committed to clear communication, dependable lead times, and consistent product excellence — so you can quote with confidence, install without worry, and grow your business with a supplier who understands what's at stake.
Start My Custom Window Journey Today
Become a Trade Partner
Installers
Your reputation matters — and we treat it with the same care as our own.
That's why we offer flexible supply options, from fully finished and glazed sash windows ready for installation, to part-finished products you can complete in your own workshop to suit your workflow and preferences.
Builders
Whether you're working on a single home or a larger residential scheme, our hardwood sash windows bring lasting value and character to your clients' properties.
With the capacity to design and manufacture to your specifications — on time and within budget — we're a reliable partner for heritage-sensitive builds and refurbishments.
Architects
We work closely with architects to design bespoke timber windows and doors that complement the overall vision of a project — ensuring
historical accuracy, material quality, and long-term performance. If you're specifying high-quality hardwood sash windows and doors, we're here to provide expert guidance on detailing, glazing options, and compliance with conservation requirements.
Our Accreditations
Frequently Asked Questions
Do you still service the residential market?
All residential works are now completed via our Approved Installation Partners.
Do the windows have to be fully finished & glazed?
Not at all. This is completely optional depending on your own facilities.
Do you manufacture in Accoya wood?
No. We only manufacture & supply Sapele timber because we believe it's a superior material over other woods.
What is the lead time for manufacture?
Standard Sash Window 6 – 8 weeks
Finished & Glazed 8 – 10 weeks
What guarantee do your windows come with?
10 Years on fully finished joinery. 5 Years guarantee on double glazed units and 1-year manufacturer's warranty on hardware.
Do you offer a credit facility?
Yes, subject to checks.