Architects Stein Hemmes Wirtz

What Architects Stein Hemmes Wirtz does

Architekten Stein Hemmes Wirtz was a German architecture partnership (PartG mbB) founded in or before the mid-1990s and registered with the Partnerschaftsregister Koblenz (PR 20291) until 31.03.2024. The firm provided full-scope architectural services across Leistungsphasen 1–9 under the German HOAI fee framework, covering new construction, renovation, conversion, and interior architecture for residential, ecclesiastical, public-sector, and commercial clients. Its core differentiator was specialization in energy-efficient and sustainable construction — in particular Passivhaus and Plus Energy House design — demonstrated through certified Passive House planning, heating demand figures as low as 14–15 kWh/m²a at the +Energiehaus Kasel and +Energiehaus Farschweiler projects, and recognition including the Internationaler Architekturpreis Passivhaus (2010), the Architekturpreis Energie Rheinland-Pfalz (2013), and the Deutscher Landbaukultur-Preis (2016). The team held scarce credentials (zertifizierte Passivhausplaner, Gebäudenergieberater, Sachverständige für Bauschäden) and delivered projects for clients including Evangelische Kirchengemeinden, BASF Wohnen + Bauen, EGP GmbH, Studierendenwerk Trier, LBB Rheinland-Pfalz, and Diakonie Pirmasens.

The firm generated revenue through project-based professional services fees, distributed via direct client engagement, public architectural competitions (Wettbewerbe), and professional network referrals in the BDA and Architektenkammer Rheinland-Pfalz ecosystems. It operated from two offices — Kasel (Rhineland-Palatinate) and Frankfurt am Main (Hessen) — and built brand recognition through 25+ state and national awards plus recurring publications in Architectural Digest, Deutsches Architektur Jahrbuch, SCHÖNER WOHNEN, and Baumeister. Customer concentration skewed toward Protestant church communities (multiple Evangelische Kirchengemeinden as repeat clients) and public-sector institutions, supplemented by private developers and corporate commissions.

In 2024 the practice executed a generational transition: the Frankfurt team continued as ROSA Wirtz Architektur PartG mbB from April 2024, and the Kasel team reorganized as Stein & Hemmes PartG mbB trading as PUR+ Architekten from July 2024. The original 'Architekten Stein Hemmes Wirtz' brand was retired on 31.03.2024. Both successor entities continue under the same energy-efficient design philosophy and the two entities remain 'freundschaftlich verbunden' (amicably connected) per the firm's farewell communication.

Name

Architects Stein Hemmes Wirtz

Legal name

Architekten Stein Hemmes Wirtz PartG mbB

Website

https://stein-hemmes-wirtz.de

Company type

Private

Operating status

Operating

Headcount range

11–50 employees

Short description

Architekten Stein Hemmes Wirtz was a German architecture partnership providing full-scope design services (HOAI Leistungsphasen 1–9) with specialization in energy-efficient Passivhaus and Plus Energy construction. Served ecclesiastical, public-sector, residential, and commercial clients across Rhineland-Palatinate, Hessen, and Saarland; split in 2024 into PUR+ Architekten and ROSA Wirtz Architektur.

Ownership category

akta.pro rank

Product category

Architectural Services

NAICS

Architectural Services (54131)

akta.pro primary industry

Residential Design-Build & Renovation-Integrated Builders (IMAFABAE)

akta.pro secondary industry

Architectural Reconfiguration & Structural Alterations (HSAPAEAB)

Keywords

• Sustainable architecture services
• Passive house design
• Plus-energy house construction
• Ecclesiastical building design
• Energy-efficient building renovation

Headquarters

HQ city

Kasel

HQ country

Germany

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Others

Revenue model

1. Architectural Design Services: Professional architectural services for new construction, renovation, and conversion projects across residential, ecclesiastical, public, and commercial sectors. Revenue generated through project-based fees for design and planning services (Leistungsphasen 1-9 according to German HOAI fee structure).

Distribution channels3 records

Marketing channels3 records

Core offering

Architekten Stein Hemmes Wirtz is a German architectural firm providing full-scope architectural design and planning services (HOAI Leistungsphasen 1-9) for new construction, renovation, and adaptive reuse projects. Core services cover residential, ecclesiastical, public/institutional, and commercial buildings, with specialized expertise in Passivhaus (passive house) and Plusenergiehaus (plus-energy house) construction, energy-efficient retrofitting, and expert assessments (energy, damage, valuation).

Product overview

Architects Stein Hemmes Wirtz is a German architecture firm providing comprehensive architectural services across residential, commercial, public, and ecclesiastical building sectors. The firm's core offerings include new construction, renovation, and adaptive reuse projects, with particular specialization in energy-efficient and Passivhaus-certified buildings. Their portfolio encompasses individual family homes, multi-family housing developments, church and community center projects, educational facilities, and commercial buildings. Notable specialized offerings include their Plus Energy house designs (+Energiehaus Kasel and +Energiehaus Farschweiler) which demonstrate leadership in sustainable construction. The firm operates from two offices: ROSA Wirtz Architektur in Frankfurt and PUR+ Architekten in Kasel, following a generational transition from the original partnership in April/July 2024.

Differentiator

Problem solved

Functional benefit

Products and services

• Residential Architecture Services Design and construction administration for single-family homes, multi-family residential buildings, and multi-generation housing developments, including Plus Energy houses built to Passivhaus standards.
• Church and Religious Building Services Design of new churches, parish halls, community centers, and the renovation, conversion, and adaptive reuse of existing ecclesiastical buildings for Protestant and Catholic communities.
• Energy-Efficient Building Design (Passivhaus / Plus Energy House) Specialized architectural services for certified Passivhaus and Plus Energy House construction, including building-integrated photovoltaics and solar thermal integration, delivered by certified Passive House planners.
• Public and Institutional Building Services Design of public buildings such as schools, kindergartens, student dormitories (Studierendenwerk), community halls, and municipal facilities, including accessible and barrier-free design.
• Commercial and Industrial Architecture Services Design of commercial buildings, office spaces, hospitality venues (hotels and restaurants), wineries, and industrial facilities for corporate clients and private operators.
• Interior Architecture Services Interior design services for residential interiors, commercial spaces, restaurants, and wine bars, including the firm's 2008 Deutscher Innenarchitekturpreis-recognized Weinhaus Becker interior.
• Building Renovation and Adaptive Reuse Services Renovation, modernization, conversion, and energetic retrofit of existing buildings, including heritage and monument preservation (Denkmalschutz) works.
• Expert Assessments and Building Consultancy Building structure analyses (Gebäudestrukturanalyse), village structure analyses (Dorfstrukturanalyse), energy assessments (Energiegutachten), property valuations (Wertgutachten), and construction defect assessments (Bauschadensgutachten) delivered by certified staff including building damage expert witnesses and building energy consultants.

Quantifiable outcome

• Heating energy demand as low as 14-15 kWh/m²a achieved in Passive House projects
• +1 more outcomes

Named customers14 records

Segments4 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

One partnership is on record.

• Matteo Thun & PartnerscoreStrategic or Co-development Partner · 1 January 2012Collaboration on the Weinkulturgut Longen-Schlöder project in Longuich. Matteo Thun & Partners contributed to the design concept for the winery extension and guest rooms, while Architekten Stein Hemmes Wirtz executed the detailed architectural design and project management.

Recent moves5 records

Expansion highlights4 records

Broad incumbents

• HPP Architekten: Düsseldorf-based full-service German architecture firm with deep public-sector and ecclesiastical heritage. Competes for many of the same German municipal and church tenders but at significantly larger scale and broader typology mix.
• gmp Architekten: Hamburg-headquartered large German practice active across stadiums, public buildings, and housing. Relevant incumbent competitor for institutional and public-sector commissions in Germany, though its portfolio is far broader and less sustainability-niche.

Direct peers

• Kadawittfeldarchitektur: Aachen-based German practice with strong credentials in sustainable building, public-sector commissions, and award-recognized residential and cultural projects. Comparable regional scale and similar mix of public + residential work.
• Werner Sobek: Stuttgart-based architecture and engineering firm specializing in sustainable, energy-efficient design including Passivhaus and zero-energy buildings. Highly comparable niche (high-performance envelopes, Plus-Energy thinking) and similar German regional base.
• Behnisch Architekten: Stuttgart-headquartered practice internationally recognized for sustainable architecture (e.g., HafenCity environmental benchmark projects). Overlaps in energy-driven design and award-winning public/institutional portfolio, but operates at meaningfully larger scale.
• Thomas Herzog Architekten: Munich-based pioneer of solar and energy-efficient architecture and long-time advocate of Passivhaus principles. Closely aligned technically — both firms treat heating energy demand as a core design parameter — though Herzog operates at a slightly higher profile.

Others

• Snøhetta: Norwegian-headquartered international practice with a strong sustainability and public-realm portfolio. Not a direct competitor (different scale, geography, fee band), but a relevant peer for design-led, sustainability-anchored commissions in Europe.
• BIG (Bjarke Ingels Group): Copenhagen/New York practice with sustainability as a defining brand pillar. Operates at a very different scale and price band, but is a comparable archetype of an architecture firm whose identity is built around performance-driven, energy-positive design narratives.

Regional players

• Dietrich | Untertrifaller: Bregenz/Dornbirn-based Austrian practice with recognized expertise in sustainable public and residential buildings. Comparable mid-size profile and sustainability orientation, but operating in Austria/Switzerland rather than Germany.
• Baumschlager Eberle: Austrian/Lake Constance architecture group with a strong sustainability and energy-efficient design philosophy. Comparable technical DNA (2000-Watt Society, Passivhaus) but anchored in the DACH region outside Stein Hemmes Wirtz's core market.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat3 records

Key risks6 records

Key highlights6 records

Customer concentration

• Facebookfacebook.com/SteinHemmesWirtz
• LinkedInlinkedin.com/company/architekten-stein-hemmes-wirtz

Revenue estimate

Valuation estimate

Number of profiles

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 Architects Stein Hemmes Wirtz