What Selectaglaze does

Selectaglaze is a UK-based specialist manufacturer and installer of secondary glazing systems, founded in 1966 and headquartered in St Albans. The company designs, manufactures, and installs bespoke aluminium-framed secondary windows that sit behind existing primary windows to deliver thermal insulation, acoustic attenuation (up to 50dB Rw reduction), intruder resistance (LPS 1175 SR1-SR3), blast mitigation (ISO 16933), and ballistic protection (EN 1522/1523). Its product range spans over 40 series variants across horizontal sliding, vertical sliding, hinged casement, fixed light, demountable, and lift-out configurations, including custom arched and shaped geometries produced via CNC bending. The company is privately held and employee-owned.

The business serves a multi-vertical UK customer base that includes heritage and listed buildings, residential homeowners, commercial offices, hotels and leisure, education, museums and libraries, healthcare, religious buildings, and government. Its go-to-market combines direct in-house technical sales consultation, site surveying, bespoke CAD design, in-house manufacturing, and installation, supplemented by a trusted partner installer network in parts of the UK where direct coverage is not available. Architect and specifier relationships are cultivated through RIBA CPD courses and NBS Source BIM/specification listings, while homeowners are reached via website content, social media, and case-study marketing. Pricing is bespoke and quote-based on project specifications.

Revenue is generated primarily through one-time sales of manufactured-and-installed secondary glazing systems, with a smaller professional services stream covering Listed Building Consent application support (CAD drawings, site surveys, Design and Access Statements). The company is recommended by Historic England for listed building work, holds a Royal Warrant, operates with 100% renewable electricity, and has been Planet Mark certified since 2019 with a stated Net Zero 2050 goal. Customer reference projects include the Grade I Listed Banqueting House, Supreme Court, St Paul's Cathedral, Tate Liverpool, and Harris Manchester College at the University of Oxford.

Name

Selectaglaze

Legal name

Selectaglaze Limited

Website

https://selectaglaze.co.uk

Company type

Private

Founded year

1966

Operating status

Operating

Headcount range

51–100 employees

Short description

Selectaglaze is a UK specialist manufacturer and installer of bespoke secondary glazing systems, serving heritage, commercial, residential, healthcare, education, religious, and government clients with thermal, acoustic, and security window upgrades that preserve original architecture.

Ownership category

akta.pro rank

Product category

Secondary Glazing Systems

NAICS

Metal Window and Door Manufacturing (332321), Ornamental and Architectural Metal Products Manufacturing (33232), Ornamental and Architectural Metal Work Manufacturing (332323)

SIC

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

akta.pro primary industry

Architectural Glazing & Fenestration (Curtain Wall, Windows, Storefronts, Skylights) (IMAFAMAC)

akta.pro secondary industries

Architectural & Building Glazing Systems (Curtain Wall/Storefront/Canopies) (IMADAHAB), Specialty Glazing (Acoustic, Blast, Bullet-Resistant, Smart/Electrochromic) (IMADAHAL)

Keywords

• Secondary glazing systems
• Heritage window retrofits
• Acoustic insulation windows
• Security glazing products
• Thermal insulation glazing

Headquarters

HQ city

Saint Albans

HQ country

United Kingdom

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Secondary Glazing Products and Installation: Bespoke secondary glazing systems sold with full in-house installation service. Products include horizontal sliding, vertical sliding, hinged casement, lift-out, fixed light, and demountable fixed light systems in various series (S10-S95). Revenue generated from product manufacturing and professional installation services.
2. Listed Building Consent Assistance: Paid service for preparing Listed Building Consent applications including CAD drawings, site surveys, and Design and Access Statements with Heritage documentation.

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels9 records

Core offering

Selectaglaze designs, manufactures, and installs bespoke secondary glazing systems that are mounted internally behind existing primary windows. The aluminium-based systems are engineered to deliver thermal insulation, acoustic noise reduction, and security protection (including blast and ballistic resistance) for heritage, commercial, and residential buildings. The full-service offering covers technical consultation, site survey, bespoke CAD design, in-house manufacturing, and professional installation across the UK.

Product overview

Selectaglaze is a bespoke secondary glazing specialist that designs, manufactures and installs secondary glazing solutions. The product portfolio consists of multiple secondary glazing system types: Horizontal Sliding (HS) series including Slimline 10, Mid-range 15, Heavy Duty 80, and Security 85 with 2-4 pane configurations; Vertical Sliding (VS) series including Slimline 20, Mid-range 25, Tilt-in 60, Heavy Duty 90/91, and Security 95 operating on spring balances; Hinged Casement (HC) series including Slimline 45, Heavy Duty 41, Heritage 47, and Security 50 with single, double, top/bottom hung and stable door options; Fixed Light (FL) series including Slimline 46, Heavy Duty/Security 42, and Half Hour Fire 40; Demountable Fixed Light (DFL) series including Heavy Duty Security 43 and High Security 55; and Lift-out (LO) series including Slimline 31, Slimline 45, and Heavy Duty 41. All systems accept various glass thicknesses and finishes to meet thermal, acoustic, and security performance requirements. The company also offers specialized Arched and Shaped Secondary Glazing for custom window geometries.

Differentiator

Problem solved

Functional benefit

Products and services

• Series 10 Slimline Horizontal Sliding Secondary Glazing A versatile horizontal sliding secondary glazing system available in 2, 3 and 4 pane configurations with slim profiles suitable for heritage properties, providing easy access for ventilation and cleaning.
• Series 15 Mid-range Horizontal Sliding Secondary Glazing A more robust horizontal sliding system in 2 or 3 pane options that allows discrete treatment of larger windows and accepts thicker glass for higher noise insulation.
• Series 80 Heavy Duty Horizontal Sliding Secondary Glazing A heavy-duty horizontal sliding system designed to treat very large windows and sliding doors with glass up to 12.8mm for higher noise insulation, accredited to Secured by Design.
• Series 85 Security Horizontal Sliding Secondary Glazing A high security horizontal sliding system providing certified levels of blast mitigation and intruder resistance to LPS 1175 SR1 and SR2 levels.
• Series 20 Slimline Vertical Sliding Secondary Glazing A vertical sliding unit operating on spring balances with slim profiles, suitable for treating traditional sash windows in heritage properties with sashes that contra slide for cleaning access.
• Series 25 Mid-range Vertical Sliding Secondary Glazing A more robust vertical sliding unit with higher capacity spring balances for treating larger windows or accepting thicker glass for higher noise insulation, accredited to Secured by Design.
• Series 60 Tilt-in Vertical Sliding Secondary Glazing A vertical sliding unit on spring balances that allows individual panes to tilt-in on safety stays for cleaning, ideal for windows with unequal pane sizes.
• Series 90 Heavy Duty Vertical Sliding Secondary Glazing A heavy-duty vertical sliding unit supported on high capacity spring balances suitable for treating sizable sash windows in Victorian and Edwardian buildings with Secured by Design accreditation.
• Series 91 Heavy Duty Vertical Sliding Secondary Glazing A vertical sliding unit on high capacity spring balances for monumental sash windows in Victorian and Edwardian buildings, accepting glass up to 12.8mm.
• Series 95 Security Vertical Sliding Secondary Glazing A high security vertical sliding unit providing certified levels of blast mitigation to ISO 16933 EXV 25 and intruder resistance to LPS 1175 SR1 and SR2 levels.
• Series 40 Half Hour Fire Rated Fixed Light Secondary Glazing A beaded fixed frame offering certified 30-minute fire integrity protection, also available with glazing beads for non-fire applications such as vision panels.
• Series 42 Heavy Duty Security Fixed Light Secondary Glazing A heavy-duty fixed frame that can be shaped and curved, accepting thicker glazing options for high noise insulation and certified blast mitigation to ISO 16933 EXV 25.
• Series 46 Slimline Fixed Light Secondary Glazing A very slim fixed frame suitable for shaped and curved windows with neat cover channels concealing fixings, Police Preferred Specification under Secured by Design.
• Series 43 Heavy Duty Demountable Fixed Light Secondary Glazing A robust demountable fixed frame offering enhanced security with minimal sight lines suitable for heritage buildings, providing SR1, SR2 and SR3 intruder resistance.
• Series 55 High Security Demountable Fixed Light Secondary Glazing A very secure demountable frame providing high levels of security including against firearms (FB4), blast mitigation to EXV 15, and LPS 1175 SR3 intruder resistance.
• Series 41 Heavy Duty Hinged Casement Secondary Glazing A versatile heavy-duty hinged casement system with flush hinges suitable for large windows and doors, accepting sealed units up to 28mm for enhanced thermal insulation.
• Series 45 Slimline Hinged Casement Secondary Glazing A hinged casement system with slim profiles and flush hinges particularly suited to heritage properties, single casement accredited to Secured by Design.
• Series 47 Heritage Hinged Casement Secondary Glazing An extremely slim hinged casement unit designed to fit within the staff bead of a traditional sash window for heritage applications.
• Series 50 Security Hinged Casement Secondary Glazing A high security casement system providing certified levels of blast mitigation up to EXV 15 and intruder resistance to LPS 1175 SR1 and SR2 levels.
• Series 31 Slimline Lift-out Secondary Glazing A lift-out secondary glazing system suitable for shaped and circular windows with slim profiles for heritage properties.
• Series 41 Heavy Duty Lift-out Secondary Glazing A lift-out version of the Series 41 casement unit suited to larger shaped and circular windows with thicker glass options for high noise insulation.
• Arched and Shaped Secondary Glazing Custom secondary glazing for one centred curves (full radius, segmented, round), two centred curves (gothic), three centred curves (pseudo ellipse), curved on plan, rakes and shapes, and combinations thereof.
• Listed Building Consent Assistance Service Paid professional service for preparing Listed Building Consent applications including CAD drawings, site surveys, and Design and Access Statements with Heritage documentation for properties requiring heritage-sensitive secondary glazing installations.
• Secondary Glazing Installation Service Full in-house professional installation service for all Selectaglaze secondary glazing products, covering the UK with in-house installers complemented by trusted partner installers in some regions. Includes site survey, technical consultation, and final installation quality assurance.

Quantifiable outcome

• Reducing heat loss through windows by up to 75%
• +4 more outcomes

Named customers18 records

Segments9 records

Ideal customer profiles9 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration1 record

Feature8 records

Partnerships

Nine partnerships are on record, tiered core and minor.

• NBS SourcecoreTechnology or IntegrationNBS Source partnership provides BIM objects, NBS Specifications and product details for construction industry professionals. Enables specifiers to access Selectaglaze product data directly within specification software.
• RIBA CPD Providers NetworkcoreGTM or Marketing PartnerRIBA CPD Providers Network member with over 550 manufacturers providing educational learning to architects. CPD is mandatory for RIBA Chartered Architects, making this a key GTM channel.
• Historic EnglandcoreStrategic or Co-development PartnerHistoric England recommends Selectaglaze for secondary glazing in listed buildings. Partnership provides credibility for heritage work.
• TP BennetminorImplementation/ SI/ Consulting PartnerArchitecture and design firm that collaborated with Selectaglaze on projects including Harris Manchester College, working on design phase to maximize thermal and acoustic properties.
• OverburyminorImplementation/ SI/ Consulting PartnerOffice fit-out specialist that worked with Selectaglaze on Harris Manchester College project as main contractor.
• Carden & Godfrey ArchitectsminorImplementation/ SI/ Consulting PartnerArchitecture firm that specified Selectaglaze products and provided positive feedback on the windows.
• Living Wage FoundationminorOthersSelectaglaze is certified as an accredited Living Wage Employer paying the real Living Wage reflecting the true cost of living.
• The 5% ClubminorOthersMembership organization working with UK employers to increase number of apprentices, sponsored students and graduates in earn and learn placements.
• ConstructionlinecoreOthersGovernment-backed procurement platform where Selectaglaze holds Gold Membership, simplifying procurement and reducing risk.

Scale indicators7 records

Recent moves6 records

Expansion highlights6 records

Market position

Competitive moat5 records

Key highlights8 records

Customer concentration

• Xx.com/selectaglaze
• YouTubeyoutube.com/user/selectaglazeltd
• LinkedInlinkedin.com/company/selectaglaze-ltd
• Instagraminstagram.com/selectaglaze_ltd

Compliance17 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles9 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 Selectaglaze