Prewett Bizley Architects

What Prewett Bizley Architects does

Prewett Bizley Architects is a UK-based architectural practice specializing in sustainable, low-energy, and low-carbon building design, with particular depth in domestic retrofit and Passivhaus standards. Founded in 2004 and operating from offices in London (118a London Wall) and Wells, Somerset, the firm is led by Bob Prewett and Graham Bizley, who have built approximately 20 years of specialist expertise in whole-house retrofit, including work on listed buildings and conservation-area properties. The practice delivers two interconnected service lines: (1) new-build low-energy houses (Dundon Passivhaus, The Orchards, Cambridge House, Quantock House) achieving near-Passivhaus air-tightness and insulation performance, and (2) deep retrofits of existing structures (Mews House Deep Retrofit, 80% House, Kilowatt House, Bruton Narrow House, Bloomsbury Town House, Malmesbury House), with a parallel practice in policy and guidance documents for public bodies including London Councils, Bristol City Council, and the Royal Borough of Kensington and Chelsea.

The firm's underlying technical platform is centred on building performance evaluation rather than software products: 12 years of post-occupancy evaluation (POE) on domestic deep retrofits provides empirical performance data that has informed published work and policy contributions, including input into the PAS 2035 retrofit standard. Project delivery relies on partnerships with specialist building physicists (Greengauge), structural engineers (Conisbee), and landscape architects (Robert Myers Associates). Thought leadership is materially reinforced by two published volumes of Architecture In Detail (Architectural Press / Taylor & Francis), covering over 120 buildings, and an extensive portfolio of RIBA National, RIBA Regional, AJ Retrofit, Passivhaus Trust, and other industry awards dating from 2004 onward.

The business model is a project-based professional services firm. Revenue is generated through architectural fees quoted by project scope, complexity, and RIBA work stages (with technical design completed at Stage 4), targeting private residential property owners seeking bespoke sustainable solutions. Customer segmentation is horizontal: the primary segment is high-net-worth private homeowners, with a secondary advisory segment comprising local authorities commissioning retrofit strategy and guidance documents. Projects are acquired through reputation, referrals, awards recognition, and press coverage in RIBA Journal, Daily Telegraph, and Architecture Today. The firm holds no external institutional investment and operates as an independent partnership with approximately six staff.

Name

Prewett Bizley Architects

Legal name

Prewett Bizley Architects

Website

https://prewettbizley.com

Company type

Private

Founded year

2004

Operating status

Operating

Headcount range

1–10 employees

Short description

Prewett Bizley Architects is a UK-based six-person architectural practice specializing in sustainable residential design, with deep expertise in building retrofit and Passivhaus standards. It serves private homeowners and public-sector clients on low-energy new builds, heritage retrofits, and retrofit policy guidance.

Ownership category

akta.pro rank

Product category

Architectural Services

NAICS

Architectural Services (54131), Architectural Services (541310)

SIC

General Bldg Contractors - Residential Bldgs (1520)

akta.pro primary industry

Architectural Design Services (BPAHAKAA)

akta.pro secondary industries

Architectural Reconfiguration & Structural Alterations (HSAPAEAB), Building Information Modeling (BIM) & Digital Design Services (BPAHAKAK)

Keywords

• Sustainable architecture
• Building retrofit
• Passivhaus design
• Low-energy construction
• Residential architecture

Headquarters

HQ city

Wells, Somerset

HQ country

United Kingdom

HQ region

Europe

Offices2 records

Markets served

GTM type

B2C

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Others

Revenue model

1. Architectural Services: Full-service architectural practice providing design, planning, technical design (RIBA Stage 4), and project oversight for residential new build and retrofit projects. Revenue is generated through project-based fees for private residential clients.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels6 records

Core offering

Prewett Bizley Architects is a UK-based sustainable architecture practice delivering full-service architectural design for residential clients. Core services include low-energy/low-carbon new-build design (including Passivhaus-standard homes) and deep retrofit of existing homes, including listed and conservation-area properties. The practice provides design, planning, technical design (RIBA Stage 4), and project oversight, with 20+ years of specialized expertise in building physics and post-occupancy performance evaluation.

Product overview

Prewett Bizley Architects is a sustainable architecture firm offering architectural design services with a focus on low-carbon and low-energy building solutions. The practice specializes in two interconnected service areas: (1) Passivhaus and low-energy new build projects including Dundon Passivhaus, The Orchards, Cambridge House, and Quantock House, and (2) building retrofit services including deep retrofits of Victorian mews houses (80% House, Mews House Deep Retrofit), listed buildings (Kilowatt House, Bruton Narrow House, Bloomsbury Town House, Malmesbury House), and modernist structures. The practice also contributes to policy and guidance documents on retrofit for public bodies. Their portfolio spans residential projects across London and Somerset, with several projects achieving Passivhaus certification or near-Passivhaus performance standards.

Differentiator

Problem solved

Functional benefit

Products and services

• Low-energy residential new-build architectural design Full-service architectural design for private residential new builds targeting Passivhaus or near-Passivhaus performance, including advanced insulation, MVHR, triple glazing, solar shading, and timber construction. Delivered for individual homeowners across the UK.

Quantifiable outcome

• Heating consumption slashed by 95% in Victorian London Mews House retrofit
• +2 more outcomes

Named customers4 records

Segments2 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

Ten partnerships are on record, tiered core and minor.

• London CouncilscoreStrategic or Co-development PartnerCollective representing all 32 London boroughs led a study into how to retrofit all of London. Prewett Bizley worked with Etude, Levitt Bernstein and Elementa to help plan a trajectory to net zero for the London housing stock. The 118-page Retrofit London Housing Action Plan was signed up to by all 33 London boroughs.
• EtudecoreStrategic or Co-development PartnerCollaborated with Prewett Bizley on the Retrofit London Housing Action Plan alongside Levitt Bernstein and Elementa.
• Levitt BernsteincoreStrategic or Co-development PartnerCollaborated with Prewett Bizley on the Retrofit London Housing Action Plan alongside Etude and Elementa.
• ElementacoreStrategic or Co-development PartnerCollaborated with Prewett Bizley on the Retrofit London Housing Action Plan alongside Etude and Levitt Bernstein.
• Bristol City CouncilminorStrategic or Co-development PartnerIn 2015, Bob worked with STBA (Sustainable Traditional Building Alliance) to produce guidance for Bristol City Council on solid wall insulation. The guide covered whole house thinking and detailing, for which archetypes were developed, modelling was carried out and detail drawings produced.
• STBA (Sustainable Traditional Building Alliance)minorStrategic or Co-development PartnerWorked with Bob Prewett to produce guidance for Bristol City Council on solid wall insulation, developing archetypes and detail drawings.
• Royal Borough of Kensington and Chelsea (RBKC)minorStrategic or Co-development PartnerFunded the ESSA Retrofit Guidance, a set of guidance commissioned by a conservation area group aimed at enabling homeowners within the conservation area to navigate their way through a retrofit project on their home.
• GreengaugecoreTechnology or IntegrationBuilding physicists brought in for thermal modelling and mechanical heating system design for the Kilowatt House retrofit project.
• RM ConstructionminorImplementation/ SI/ Consulting PartnerMain contractor for Cambridge House project.
• Institute of SustainabilityminorStrategic or Co-development PartnerOne of 12 guides on domestic retrofit produced for the Institute of Sustainability in 2011, focusing on managing projects and written by Bob Prewett. Set out the idea of a 'retrofit coordinator', a new role that would become the bedrock of the PAS 2035 standard.

Scale indicators6 records

Recent moves6 records

Expansion highlights5 records

Broad incumbents

• Allies and Morrison: Established UK architecture firm working across residential, commercial, and masterplanning projects with sustainability embedded across a broader portfolio. Operates as a larger incumbent in the same architectural services space as Prewett Bizley.
• Foster + Partners: Global architecture practice with strong sustainability credentials and a wide portfolio spanning residential, commercial, and institutional buildings. A broad incumbent that operates in the same low-energy design space but at vastly larger scale and global reach.

Direct peers

• Haworth Tompkins: Award-winning UK architecture firm known for sustainable design across residential, cultural, and heritage projects. Comparable to Prewett Bizley in retrofit expertise, RIBA award recognition, and depth of practice in low-energy building design.
• Cullinan Studio: Established UK architecture firm with a long-standing reputation for sustainable, low-energy design and heritage-led projects. Comparable to Prewett Bizley in emphasis on environmental performance and listed-building expertise.
• Purcell: UK heritage architecture firm with deep expertise in listed-building and conservation-area work. Comparable to Prewett Bizley in retrofit focus on heritage assets and navigating complex planning and conservation constraints.
• Levitt Bernstein: UK architecture and planning practice with a strong focus on sustainable housing design and retrofit. Partnered with Prewett Bizley on the Retrofit London Housing Action Plan, indicating directly overlapping expertise in residential retrofit and net-zero housing strategy.
• Bere: Architects: UK sustainable architecture practice with strong emphasis on low-energy design, Passivhaus, and timber construction. Similar boutique scale and shared focus on low-carbon residential and small-scale community projects.
• Mikhail Riches: London-based architecture practice specializing in sustainable, low-carbon residential design and Passivhaus construction (RIBA Stirling Prize 2019). Highly comparable to Prewett Bizley in client base, Passivhaus expertise, and emphasis on evidence-based sustainability.
• Elementa Consulting: UK sustainable building engineering consultancy focused on low-energy retrofit and policy. Partnered with Prewett Bizley on the Retrofit London Housing Action Plan and shares overlapping sustainability and retrofit advisory expertise.
• John Pardey Architects: UK-based architectural practice recognized for Passivhaus-standard residential design and contemporary low-energy housing. Comparable to Prewett Bizley in Passivhaus specialization and rural/contemporary residential client base.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat5 records

Key risks5 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/prewett-bizley-architects
• Instagraminstagram.com/prewettbizleyarchitects

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Funding overview

Funding rounds

Investors

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

M&A

Investments

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Frequently asked questions about Prewett Bizley Architects