What Clement Windows does

Clement Windows Group Ltd is a privately-held UK specialist manufacturer and installer of steel windows, doors, screens and conservation rooflights, headquartered in Haslemere, Surrey, with manufacturing operations owned through a Polish subsidiary (Clement Polska sp.z. o.o.) operating ISO 9001 and ISO 14001 approved facilities capable of producing up to 800 bespoke windows and doors per week. Founded in 2010, the group serves three core customer groups — residential homeowners (especially for period and listed-building replacement), architects and specifiers, and commercial projects including heritage hotel and Grade II redevelopments — with marquee installations including The Brewhouse Malta, 71 Nyhavn Hotel Copenhagen and the Eldorado Apartment Building in Manhattan. The product portfolio spans the EB24, EB20, EB16 and W20 steel window ranges, steel doors and screens, and a Conservation Rooflights line stocked in eight standard sizes with bespoke options.

Core technology centres on hot-rolled steel window and door profiles sourced from 98% recycled steel, manufactured through cold-forming, welding, hot dip galvanising and polyester powder coat painting, with thermally broken steel systems developed in partnership with Jansen and high-specification vacuum-insulated single glazing offered via the AGC/Panasonic FINEO partnership. The business model is sales-led and specification-driven: revenue is generated via bespoke quotations (no public price list), multi-year project contracts, and value-added services including technical drawings, RIBA-accredited CPD presentations, manufacture, installation and after-sales support. Marketing relies on the company website, RIBA CPD sessions, NBS Source platform integration, Houzz profile and direct engagement with architects, while downstream distribution flows through two UK sales-facing subsidiaries (Clement Windows Ltd for residential and Clement Projects Ltd for commercial) feeding the centralised Polish production entity. International reach spans the UK, USA and continental Europe, supported by trademarks registered across UK, EU and USA.

Name

Clement Windows

Legal name

Clement Windows Group Ltd

Website

https://clementwindows.co.uk

Company type

Private

Founded year

2010

Operating status

Operating

Short description

Clement Windows is a UK-based specialist manufacturer and installer of bespoke steel windows, doors, screens and conservation rooflights, serving residential homeowners, architects/specifiers and commercial heritage projects across the UK, USA and Europe.

Ownership category

akta.pro rank

Product category

Steel Fenestration Manufacturing

NAICS

Metal Window and Door Manufacturing (332321)

SIC

Metal Doors, Sash, Frames, Moldings & Trim (3442)

akta.pro primary industry

Windows (IMADAIAC)

akta.pro secondary industries

Interior Doors (IMADAIAB), Frames, Sashes, Mullions & Subframes (IMADAIAH), Custom Window & Door Fabrication & Replacement (HSAPAJAI)

Keywords

• Steel window manufacturing
• Conservation rooflights
• Heritage fenestration products
• Thermally broken steel doors
• Listed building windows

Headquarters

HQ city

Haslemere

HQ country

United Kingdom

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B and B2C

Offering type

Hardware or Manufacturing

Cost components

Personnel, Supply Chain, Operations, Marketing or Sales, Technology or R&D, Infrastructure

Revenue model

1. Steel Windows and Doors: Sale of bespoke steel windows and doors manufactured to customer specifications, including replacement and new-build applications for residential and commercial projects.
2. Conservation Rooflights: Standard and bespoke conservation rooflights available from stock in tile or slate profiles, with bespoke manufacturing capabilities for custom designs.
3. Installation Services: Complete service including technical drawings, manufacture, installation and after-sales support for steel fenestration products.

Pricing tiers

Go-to-market motion1 record

Distribution channels2 records

Marketing channels5 records

Core offering

Clement Windows Group designs, manufactures, and installs bespoke steel windows, steel doors and screens, and conservation rooflights. All products are produced in their own ISO 9001 and ISO 14001 approved factory in Poland, using hot dip galvanising and polyester powder coat paint finishing, with thermally broken steel systems for modern thermal performance. The company provides a complete service from technical drawings through manufacture, installation, and after-sales support.

Product overview

Clement Windows Group is a specialist manufacturer and installer of steel window fenestration products. The company offers a unified portfolio of three core product lines: Steel Windows (available in EB24, EB20, and W20 ranges), Steel Doors & Screens, and Conservation Rooflights. These products are complemented by specialist services for Listed & Heritage Projects. All products are manufactured in the company's own ISO 9001 and ISO 14001 approved factory in Poland, with operations rooted in the UK. The company provides a complete service from technical drawings through to manufacture, installation and after-sales support, serving both residential clients and building professionals.

Differentiator

Problem solved

Functional benefit

Brands

• EB16: Steel window range
• EB20
• EB24
• Clement Conservation Rooflights
• Brooking
• Naked Steel

Products and services

• Steel Windows Steel windows with slim and elegant sightlines available in EB24, EB20, and W20 ranges. New or replacement windows deliver lower energy bills, greater security, noise reduction, and thermal efficiency. Specialises in replication of existing windows for heritage and conservation objectives, for residential and commercial clients.
• Steel Doors & Screens Steel doors and screens made from slim steel sections, offered with multi-point locking or traditional mortice lock. Available in a range of colours with safety glass as standard and glazing options for fireproofing, security, solar and acoustic requirements.
• Conservation Rooflights Modern replicas of Victorian original conservation rooflights manufactured from mild steel sheet. Available in eight standard sizes for tile or slate profile, or bespoke sizes. Features 24mm insulated glass units, argon gas filled units, and self-cleaning glass as standard. Rooflights lie flush with the roof line when installed.
• Listed & Heritage Projects Service Specialist service for projects involving Listed Buildings or Conservation Areas, providing thermally broken steel windows and doors that meet modern thermal performance requirements while respecting heritage objectives. Includes technical drawings, manufacture, installation and after-sales support.
• EB24 Steel Window Range Premium thermally broken steel window profile featuring slim sightlines, multi-point locking, and excellent thermal performance. Manufactured from hot rolled steel window and door profiles produced from 98% recycled steel source material. Used in both residential and commercial projects including prestigious installations.
• EB20 Steel Window Range Mid-range steel window offering balanced aesthetics and performance for residential and commercial applications, with slim profiles suitable for heritage and modern applications.
• W20 Steel Window Range Steel window range designed for various residential and commercial applications.

Named customers3 records

Segments3 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration1 record

Feature4 records

Partnerships

Three partnerships are on record, tiered core.

• JansencoreTechnology or IntegrationGlobal leader and systems supplier for cold-formed thermally broken steel systems. Clement has established links with Jansen's systems suppliers as one of the leading producers of thermally broken steel systems for the industry.
• AGC/Panasonic (FINEO)coreTechnology or IntegrationAGC/Panasonic joint venture partnership on FINEO - a high specification single glazing product that outperforms double glazing in u-values. Clement is a partner for this innovative glazing solution.
• Global Galvanising LeaderscoreStrategic or Co-development PartnerEstablished relationships with world leading partners for galvanising and polyester powder coat paint services, ensuring high quality finish for all steel window products.

Scale indicators2 records

Recent moves6 records

Expansion highlights6 records

Broad incumbents

• Marvin Windows and Doors: Large US window and door manufacturer offering a wide range of materials including a premium Signature/Ultimate line used in architect-specified projects. Comparable to Clement as a higher-end architectural specification brand, though much broader in materials and scale.

Direct peers

• Hope's Windows: US-based manufacturer of steel windows and doors for landmark commercial, institutional and residential projects. Comparable to Clement in steel material focus, premium positioning and heritage-grade fenestration, though serving primarily the North American market.
• Crittall Windows: UK's most iconic steel window manufacturer with a long heritage of supplying metal windows for residential, commercial and conservation projects. Most directly comparable peer given overlapping product categories (steel windows and doors), customer base (heritage and architects), and UK distribution.
• Steel Window Service Company: UK steel window manufacturer and refurbishment specialist targeting listed building and conservation projects. Comparable to Clement's heritage fenestration focus and Slim-profile W20/EB-style product range.
• Artisan Metal Windows: UK specialist fabricator of steel windows and doors for period properties, listed buildings and bespoke new-builds. Direct overlap with Clement's heritage replacement proposition and Slimline/standard steel window offerings.
• W20 Steel Windows: UK manufacturer of W20-series steel windows and doors for heritage, conservation and contemporary projects. Directly comparable product line, target customer (architects and homeowners) and use cases (listed building replacement).
• Brombal: US/European manufacturer specializing in thermally broken steel, bronze and stainless steel window and door systems. Directly comparable premium metal fenestration range targeting architects for residential and commercial projects, including heritage restoration.
• Fendor Limited: UK-based manufacturer of steel and aluminium windows and doors serving heritage and commercial applications. Comparable to Clement in metal fenestration focus and architectural specification channel.

Others

• Jansen: Swiss manufacturer of cold-formed steel profiles and a systems supplier for thermally broken steel windows and doors. Listed as a Clement technology partner and comparable as the upstream steel systems platform used across the European steel window industry.

Emerging players

• Vitrocsa: Manufacturer of ultra-slim framed steel and aluminium window, door and sliding systems targeting high-end architectural and residential projects. Comparable to Clement in premium slimline positioning and use on prestigious heritage/commercial briefs, though with a different mechanism focus.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights7 records

Customer concentration

Compliance14 records

Revenue estimate

Valuation estimate

Number of profiles

Subsidiaries3 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Clement Windows