Sternfenster
Sternfenster is a family-run UK trade fabricator, established 1974 in Lincoln, manufacturing uPVC and aluminium windows and doors for a national Approved Installer Network, with sub-brands StyleLine and TimberLine and an in-house quoting platform, EasyAdmin+.
- Company typePrivate
- Founded1974
- HeadquartersLincoln, United Kingdom
- Headcount101–250
- GTM typeB2B
- OfferingHardware or Manufacturing
What Sternfenster does
Sternfenster (legal entity Starglaze Windows and Conservatories Limited) is a family-run UK trade fabricator of uPVC and aluminium windows and doors, founded in 1974 and headquartered in Lincoln. The company manufactures from a single 80,000-square-foot facility equipped with automated CNC mitring, automated glass lines, in-house colour spraying, and just-in-time production practices, enabling lead times of as little as five days against an industry standard closer to five weeks. It was the first UK fabricator to adopt Graf Synergy seamless graf-weld technology on uPVC and offers proprietary sub-brands (StyleLine, TimberLine) alongside Deceuninck uPVC profiles and Smart Systems aluminium systems. Product breadth covers casement, flush, tilt-and-turn, vertical sliding sash, bifold, patio, composite, GRiPCORE, commercial curtain walling, and shopfronts, with MACO smart sensors added as a connected-hardware overlay.
Sternfenster firmographics
Firmographics- Name
- Sternfenster
- Legal name
- Starglaze Windows and Conservatories Limited
- Website
- https://sternfenster.com
- Company type
- Private
- Founded year
- 1974
- Operating status
- Operating
- Headcount range
- 101–250 employees
- Short description
- Sternfenster is a family-run UK trade fabricator, established 1974 in Lincoln, manufacturing uPVC and aluminium windows and doors for a national Approved Installer Network, with sub-brands StyleLine and TimberLine and an in-house quoting platform, EasyAdmin+.
- Ownership category
- akta.pro rank
Sternfenster industry classification
Industry- Product category
- Fenestration products manufacturing (uPVC and aluminium windows and doors)
- NAICS
- Metal Window and Door Manufacturing (332321)
- SIC
- Metal Doors, Sash, Frames, Moldings & Trim (3442)
- akta.pro primary industry
- Doors, Windows & Millwork Retail (Interior/Exterior Doors, Windows, Moulding) (CRAIAEAI)
- akta.pro secondary industry
- Aluminum Value-Added Components (Automotive, Aerospace, Packaging, Building Systems) (IMAKACAM)
Keywords
Where Sternfenster is headquartered
LocationHeadquarters
- HQ city
- Lincoln
- HQ country
- United Kingdom
- HQ region
- Europe
Offices1 record
Markets served
Sternfenster business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Supply Chain, Personnel, Operations, Marketing or Sales, Technology or R&D
Revenue model
- Windows and Doors Manufacturing and Sales: Sternfenster manufactures and sells a comprehensive range of uPVC and aluminium windows and doors to trade customers and installers. Products are sold via the Approved Installer Network and direct trade relationships. Payment terms include cash with order (CWO) and credit accounts.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Transaction based/ take rate | Pay-as-you-go | Cash With Order (CWO) - Standard trade payment terms |
| Transaction based/ take rate | Monthly | Credit Account - Subject to credit check and approval |
Go-to-market motion1 record
Distribution channels3 records
Marketing channels9 records
Sternfenster product offering
Product offeringCore offering
Sternfenster manufactures uPVC and aluminium windows and doors from an 80,000 sq ft facility in Lincoln, UK, supplying trade installers via its Approved Installer Network. The product range spans uPVC windows, aluminium windows, and multiple door lines including uPVC, aluminium, composite, Gripcore, and flush variants, supported by EasyAdmin+ quoting software for trade customers.
Product overview
Sternfenster is a multi-award-winning manufacturer and fabricator of uPVC and aluminium windows and doors, established since 1974. The company operates from an 80,000-square-foot factory in Lincoln, UK, supplying trade customers and homeowners through an Approved Installer Network. Their product portfolio centers on Deceuninck uPVC windows and doors (Casement, Flush Casement, Tilt & Turn, StyleLine, TimberLine, Composite, Gripcore, Flush) and Smart Systems aluminium windows and doors (Smart, Alitherm, Bifold, Patio, Residential, Commercial, Curtain Walling, Smart Doors). Supporting products include glass sealed units (Planitherm), MACO smart sensors for connected home features, and the EasyAdmin+ quoting software platform for trade customers. The company emphasizes fast lead times (from 5 days), sustainability (Net Zero 2050 commitment), and exclusive proprietary ranges (StyleLine, TimberLine).
Differentiator
Problem solved
Functional benefit
Products and services
- uPVC windows uPVC-framed window systems manufactured in Lincoln, UK, supplied through the Approved Installer Network to trade customers for residential installations.
- Aluminium windows Aluminium-framed window systems produced in-house by Sternfenster and supplied via the Approved Installer Network for trade and commercial applications.
- uPVC doors uPVC entrance and back door systems manufactured by Sternfenster and supplied to trade installers through the Approved Installer Network.
- Aluminium doors Aluminium entrance and bifold door systems fabricated in-house by Sternfenster and distributed to trade installer partners.
- Composite doors Composite front entrance door range manufactured by Sternfenster and supplied to Approved Installer Network members for residential projects.
- Gripcore doors Sternfenster-branded Gripcore door range supplied to trade customers for installation in UK residential projects.
- Flush doors Flush-fit door systems manufactured by Sternfenster and offered through its Approved Installer Network.
- EasyAdmin+ Trade-focused quoting, ordering, and account management software platform used by Approved Installer Network members to price and order Sternfenster windows and doors.
Quantifiable outcome
- Products manufactured from just 5 days lead time, faster than the typical 5-week industry standard
- +4 more outcomes
Companies that use Sternfenster
Customer profileNamed customers4 records
Segments3 records
Ideal customer profiles1 record
Sternfenster technology and API
TechnologyTechnology focussed No
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature5 records
Sternfenster partnerships and signals
Strategic signalPartnerships
Six partnerships are on record, tiered core and minor.
- DeceuninckcoreDeceuninck is a key supply partner providing award-winning uPVC window and door profiles to Sternfenster. As a proud supplier, Sternfenster manufactures products using Deceuninck's market-leading uPVC profiles, offering high performance thermal efficiency, superior designs, and an award-winning colour range. Deceuninck products enable Sternfenster to supply products suited for a vast range of residential and commercial projects.
- Smart Systems (SMART)coreSmart Systems (SMART) is a long-standing aluminium systems partner supplying high-quality aluminium profiles and systems. The partnership enables Sternfenster to offer a wide range of contemporary aluminium windows, doors, and systems including Smart Aluminium Windows, Alitherm ranges, and commercial aluminium products. SMART provides cutting-edge design, thermal break technology, and extensive customisation options through RAL colours.
- DoorCocoreDoorCo is a key supply partner providing composite door solutions, specifically the Gripcore range. DoorCo and Sternfenster collaborate on innovative door technology, delivering advanced thermal performance composite doors with GRiPCORE technology that offers greater thermal efficiency and performance than comparable products.
- MACOcoreMACO provides multi-point locking systems and smart window/door sensors integrated into Sternfenster's aluminium windows and doors. MACO technology offers advanced security through multi-point locking mechanisms, energy efficiency through airtight seals, and smart home functionality through sensors that monitor open/closed states. MACO is a leading European hardware manufacturer for windows and doors.
- Graf SynergycoreGraf Synergy supplied the seamless welding technology that made Sternfenster the first UK fabricator to offer seamless graf-weld on uPVC windows and doors. This pioneering technology adoption set a new standard in uPVC manufacturing quality, representing a significant strategic partnership for manufacturing innovation.
- LASCO MarketingminorLASCO Marketing is a third-party marketing partner that provides prizes and promotional services for Sternfenster's 50th anniversary Spin-to-Win campaign. Details of participants in the promotion may be shared with LASCO for marketing purposes.
Scale indicators6 records
Recent moves6 records
Expansion highlights6 records
Sternfenster competitors and assessment
Company assessmentBroad incumbents
- Everest Home Improvements: One of the UK's largest home improvement companies manufacturing and installing uPVC and aluminium windows and doors. Comparable to Sternfenster on product category and trade/installer distribution, but operates at significantly greater scale with national consumer marketing.
- Safestyle UK: UK-listed (formerly) volume installer and manufacturer of uPVC windows and doors. Closely comparable on product mix and trade customer focus, with a much larger consumer-facing sales operation than Sternfenster.
- Anglian Home Improvements: Major UK home improvements group manufacturing and installing windows, doors, and broader home improvement products. Direct overlap on uPVC and aluminium windows and doors, with national brand reach.
- Reynaers Aluminium: European aluminium systems supplier and window/door solutions provider. Comparable on aluminium systems technology and architectural product range, though primarily upstream as a systems house rather than fabricator.
Direct peers
- Origin Global: UK aluminium windows and doors manufacturer with a strong trade and installer network, similar in product focus to Sternfenster's aluminium range. Closely comparable on premium aluminium positioning and bespoke finishes.
- CR Smith: Scottish-based uPVC and aluminium window and door manufacturer serving UK trade customers. Comparable regional fabricator model with installer network distribution and similar product breadth to Sternfenster.
- Solidor: UK composite door manufacturer supplying trade and installer channels. Directly comparable to Sternfenster's DoorCo GRiPCORE composite door offering and overlapping installer customer base.
- Zenith Staybrite: UK windows and doors manufacturer and installer focused on trade and retail customers. Comparable mid-market fabricator with similar product categories and installer-led distribution model.
- Cloudy2Clear Windows: UK national window and door repair and replacement company operating through local franchisees. Comparable on installer-led model and UK residential replacement focus.
Others
- Deceuninck: Sternfenster's core uPVC profile supplier and global systems house. Directly comparable on window/door product category; relevant as a partner and ecosystem participant rather than a competing fabricator.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat6 records
Key risks6 records
Key highlights7 records
Customer concentration
Sternfenster social profiles
Digital presenceSternfenster compliance and trust
Trust signalCompliance6 records
Sternfenster financial estimates
Financial estimateRevenue estimate
Valuation estimate
Sternfenster leadership team
Management profileNumber of profiles
Sternfenster funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Sternfenster M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Sternfenster
What does Sternfenster do?
Sternfenster manufactures uPVC and aluminium windows and doors from an 80,000 sq ft facility in Lincoln, UK, supplying trade installers via its Approved Installer Network. The product range spans uPVC windows, aluminium windows, and multiple door lines including uPVC, aluminium, composite, Gripcore, and flush variants, supported by EasyAdmin+ quoting software for trade customers.
Is Sternfenster a public or private company?
Sternfenster is a private company. It is classified as family owned and is currently operating.
When was Sternfenster founded?
Sternfenster was founded in 1974. It employs 101 to 250 people.
Where is Sternfenster based?
Sternfenster is headquartered in Lincoln, United Kingdom, in the Europe region.
How does Sternfenster make money?
One revenue line is on record: windows and Doors Manufacturing and Sales.
Who are Sternfenster's main competitors?
Broad incumbents on record are Everest Home Improvements, Safestyle UK, Anglian Home Improvements and Reynaers Aluminium. Direct peers are Origin Global, CR Smith, Solidor, Zenith Staybrite and Cloudy2Clear Windows. Deceuninck is listed as an others.
Does Sternfenster have an API?
No public API is recorded for Sternfenster.
What industry is Sternfenster in?
Sternfenster's product category is Fenestration products manufacturing (uPVC and aluminium windows and doors). Its primary akta.pro industry code is CRAIAEAI, Doors, Windows & Millwork Retail (Interior/Exterior Doors, Windows, Moulding), with a secondary code of IMAKACAM, Aluminum Value-Added Components (Automotive, Aerospace, Packaging, Building Systems). Its NAICS code is 332321 and its SIC code is 3442.