Rationel

What Rationel does

Rationel is a Danish manufacturer of energy-efficient windows and doors, established in the 1950s and operating under the DOVISTA A/S conglomerate (CVR 21147583, headquartered in Horsens, Denmark). The company produces approximately 300,000 windows and doors annually from its factories in Denmark, organized around four core product series: AURA and AURAPLUS (modern designs with smooth fill panels) and FORMA and FORMAPLUS (classic designs with profiled fill panels), where the PLUS variants add aluminum exterior cladding for extended durability. The portfolio spans fixed, top-hung, side-hung, tilt-and-turn, and specialty-shaped windows alongside exterior, terrace, balcony, and lift-slide doors, with supplementary offerings including fire-rated elements, shutter panels, and ECOLINE CO2-reduced glass launched in 2025. Henrik Kjeldsen serves as CEO (adm. direktør) and the operating headquarters is in Herning.

The go-to-market relies exclusively on a nationwide network of more than 250 authorized builders' merchants and timber yards across Denmark—including anchor chains Bygma, STARK, Bauhaus, XL-BYG, Davidsen, 10-4, and Fog—with no direct sales channel. Pricing for windows and doors is quote-based through dealers, while accessories and spare parts (handles, hinges, sealing strips, cylinders, brackets) are sold at fixed prices via the Rationel webshop. Customers are primarily private Danish homeowners undertaking renovation or new-build projects, with secondary segments of professional builders and prefabricated home manufacturers requiring standardized specifications and volume pricing.

Rationel supports its channel with substantial professional infrastructure: technical documentation, Revit files, performance declarations (DOP), EPD overviews, Window School training, and a digital toolkit (Window Designer, Door Designer, Energy Calculator, and a mobile app) for visualization and lead qualification. The company holds CO2 neutral certification (Ingen CO2, ID 1663), FSC chain-of-custody, CE marking under EN14351-1, DGNB sustainable-building compliance, and Dansk Vindue Verifikation, reflecting an ESG positioning aligned with Denmark's tightening building and emissions regulations. Rationel operates only in Denmark under its own brand, with no disclosed organic export activity.

Name

Rationel

Legal name

DOVISTA A/S

Website

https://rationel.dk

Company type

Private

Founded year

1950

Operating status

Operating

Headcount range

501–1,000 employees

Short description

Rationel is a Danish manufacturer of energy-efficient windows and doors, producing approximately 300,000 units annually under DOVISTA A/S and distributing exclusively through 250+ builders' merchants and timber yards across Denmark for homeowners and professional builders.

Ownership category

akta.pro rank

Product category

Windows and Doors Manufacturing

NAICS

Wood Window and Door Manufacturing (321911)

SIC

Millwood, Veneer, Plywood, & Structural Wood Members (2430), Wholesale-Lumber, Plywood, Millwork & Wood Panels (5031)

akta.pro primary industry

Custom Window & Door Fabrication & Replacement (HSAPAJAI)

akta.pro secondary industries

Doors, Windows & Millwork Retail (Interior/Exterior Doors, Windows, Moulding) (CRAIAEAI), Windows, Doors & Millwork Distribution (CRAOAFAI)

Keywords

• Energy-efficient windows
• Wood aluminum doors
• Window manufacturer Denmark
• Exterior entrance doors
• Fire-rated window elements

Headquarters

HQ city

Herning

HQ country

Denmark

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B and B2C

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Windows and doors sales: Rationel manufactures and sells windows and doors through a network of over 250 builders' merchants and timber yards across Denmark. Products include various window types (fixed frame, top-hung, side-hung, tilt-and-turn, etc.) and door types (exterior doors, terrace doors, balcony doors, lift-slide doors). Both private homeowners and professional builders are customers.
2. Accessories and spare parts: Online webshop selling accessories, spare parts, handles, hinges, sealing strips, locks, and other components for Rationel windows and doors. Available to both consumers and professionals.

Pricing tiers

Go-to-market motion2 records

Distribution channels3 records

Marketing channels6 records

Core offering

Rationel manufactures and sells energy-efficient wooden and wood/aluminum composite windows and doors in Denmark, organized around four main series (AURA, AURAPLUS, FORMA, FORMAPLUS). The company produces approximately 300,000 windows and doors annually and distributes them exclusively through a nationwide network of over 250 authorized builders' merchants and timber yards.

Product overview

Rationel is a Danish manufacturer of high-quality windows and doors operating under DOVISTA A/S. The product portfolio is organized around four main window series: AURA and AURAPLUS (modern style, smooth fill panels) and FORMA and FORMAPLUS (classic style, profiled fill panels). AURA and FORMA are wooden windows, while AURAPLUS and FORMAPLUS are wood/aluminum composite versions with aluminum cladding on the exterior. The company offers extensive window variety including fixed windows, top-hung, side-hung, tilt-and-turn, and special shapes, as well as door products including exterior doors (available as facade/rammedøre or plate/pladedøre), terrace doors, balcony doors, and lift-sliding doors. Fire-rated elements and shutter panels are also available. Accessories include handles, hinges, brackets, sealing strips, latches, and brakes sold through the online spare parts shop. Recent innovation includes ECOLINE CO2-reduced glass. Digital tools include a Door Designer, Window Designer, Energy Calculator, and mobile app for visualization.

Differentiator

Problem solved

Functional benefit

Brands

• Rationel AURA: Modern window and door product series with contemporary design
• Rationel AURAPLUS
• Rationel FORMA
• Rationel FORMAPLUS
• ECOLINE

Products and services

• AURA Window Series Modern wooden window series with smooth fill panels for contemporary building styles, available with 2-layer or 3-layer glass options.
• AURAPLUS Window Series Modern wood/aluminum composite window series with smooth fill panels, combining wood interior with aluminum exterior cladding for enhanced durability.
• FORMA Window Series Classic wooden window series with profiled fill panels, designed for traditional architectural styles.
• FORMAPLUS Window Series Classic wood/aluminum composite window series with profiled fill panels for traditional architecture, combining wood interior with aluminum exterior cladding.
• Exterior Entrance Doors (Yderdøre) Main entrance doors available as facade doors (rammedøre) with frame construction or plate doors (pladedøre) with layered construction, with inward or outward opening options.
• Terrace Doors (Terrassedøre) French doors for terrace access, available with door profile or window profile.
• Balcony Doors (Altandøre) Doors designed for balcony access.
• Lift-Sliding Doors (Hæveskydedøre) Large sliding doors that lift when opening, providing wide opening and thermal efficiency.
• Fire-Rated Elements (Brandelementer) Fire-rated windows and doors for fire compartmentation requirements and safety compliance.
• ECOLINE CO2-Reduced Glass CO2-reduced glass that contributes to environmental sustainability and supports the green transition; available as a glass option across Rationel windows and doors.
• Window and Door Accessories and Spare Parts Online retail offering handles, hinges, brackets, sealing strips, latches, brakes, fresh air vents, cylinders, PN security fittings, window holders, cover caps, and storm hooks for Rationel windows and doors.

Quantifiable outcome

• 300,000 windows and doors shipped annually from factories
• +1 more outcomes

Named customers7 records

Segments3 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature6 records

Partnerships

Eight partnerships are on record, tiered core.

• DOVISTA A/ScoreOthersDOVISTA A/S is the parent company and trademark owner of Rationel. Rationel is a brand used under license from DOVISTA A/S, which is headquartered in Horsens, Denmark (Bygholm Søpark 21D, 8700 Horsens, CVR 21147583). DOVISTA operates multiple window and door brands across Northern Europe.
• BygmacoreChannel Partner/ Reseller/ DistributorMajor nationwide builders' merchant chain serving as primary distribution channel for Rationel products. Bygma has showrooms displaying Rationel windows and doors across Denmark.
• STARKcoreChannel Partner/ Reseller/ DistributorMajor nationwide builders' merchant chain serving as primary distribution channel for Rationel products.
• DavidsencoreChannel Partner/ Reseller/ DistributorBuilding materials supplier serving as distribution channel for Rationel products with showrooms across Denmark.
• BauhauscoreChannel Partner/ Reseller/ DistributorDIY and building materials retailer chain with Rationel product displays in showrooms across Denmark.
• XL-BYGcoreChannel Partner/ Reseller/ DistributorBuilding materials cooperative chain serving as distribution channel for Rationel products.
• 10-4coreChannel Partner/ Reseller/ DistributorBuilding materials retailer chain with showrooms displaying Rationel windows and doors.
• FogcoreChannel Partner/ Reseller/ DistributorTimber and building materials supplier with showrooms for Rationel product display.

Scale indicators4 records

Recent moves5 records

Expansion highlights5 records

Direct peers

• VELFAC: Danish manufacturer of wood and wood/aluminum windows and doors, also part of the DOVISTA group. Most direct peer — same product categories, same Danish market, similar distribution through builders' merchants.
• Idealcombi: Danish manufacturer of energy-efficient windows and exterior doors in wood, wood/aluminum, and composite materials. Directly comparable in product range, target customer (Danish homeowners and builders), and channel (dealer network).
• Vindum Vinduer: Danish wood window manufacturer serving both new-build and renovation segments. Comparable in product (wood windows and doors), customer base, and Danish dealer-led distribution model.
• Krone Vinduer: Danish manufacturer of wood and wood/aluminum windows and doors. Comparable product offering, Danish focus, and reliance on builders' merchants and timber yards for distribution.
• Outrup Vinduer & Døre: Danish wood window and exterior door manufacturer serving residential renovation and new-build customers. Similar product categories (wood windows/doors) and channel approach via Danish dealers.

Broad incumbents

• Reynaers Aluminium: Belgian manufacturer of aluminum window, door, and facade systems across Europe. Comparable in premium architectural fenestration and sustainability focus; broader portfolio and geographic reach than Rationel.
• Schüco: German global systems provider for windows, doors, and facades. Overlaps with Rationel in premium window and door systems but operates at much larger scale across commercial and residential segments.
• Internorm: Austria-based European leader in windows and doors (wood, wood/aluminum, uPVC, uPVC/aluminum). Comparable in premium energy-efficient product positioning and sustainability credentials; broader European footprint than Rationel.

Regional players

• Solid AS: Norwegian manufacturer of wood and wood/aluminum windows and doors for the Nordic residential market. Comparable product range and premium energy-efficiency positioning; primarily serves Norway rather than Denmark.

Others

• Bygma: One of Denmark's largest builders' merchants and a key distribution partner for Rationel. Listed because of its role in Rationel's go-to-market and its position as a representative channel intermediary for fenestration products in Denmark.

Market position

Strengths1 record

Competitive moat5 records

Key highlights7 records

Customer concentration

• YouTubeyoutube.com/user/rationelvindueras
• Facebookfacebook.com/RationelVinduer
• LinkedInlinkedin.com/company/rationel-vinduer-as

Compliance4 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

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 Rationel