BSD Passivhaus Head Quarters, Kettering

Design team:


Building Services Design

Project Manager: 

JB Associates


Leaf Architecture

Structural Engineer: 

Lightfoot Design

Main Contractor: 

Aragon Homes

BSD showcases their energy credentials with their new Head Office



Founded in 1991 and with a track record of successful projects, BSD is now one of the UK’s top 30 Mechanical & Electrical consultancies, employing over 80 people in seven strategically located offices. As the company grows from strength to strength it became time to build their own showcase Head Office in a style that would reflect their core beliefs and values.



Passivhaus standard provides a very high level of efficiency with the aim of minimising ‘ongoing’ running costs, whilst also providing optimum thermal comfort to the occupants. Certification for this standard requires design optimisation at every stage of the design and construction process. The challenge was to meet the key principals of Passivhaus:

• Be Lean: the first phase is to increase the base energy performance of the building, by improving the fabric U-values, so reducing base energy demands.

• Be Clean: the second phase is to use most efficient plant and equipment, such as LED lighting and controls, high efficiency heating, cooling and ventilation plant, so reducing energy usage.

•Be Green: the third phase is to consider the use of renewable energy technologies, such as PV panels, so mitigating base energy demands.



The design approach follows a hierarchical triple approach design strategy, to comply with planning guidance, Part L of the Building Regulations, and reduce carbon dioxide emissions, from a building’s heating, cooling and lighting energy usage.

The building has a timber frame with extremely high performing wall insulation, cavity and brick with rendered blockwork and cedar cladding for external treatment.

Openable triple glazed windows provide high thermal and solar properties, in addition to cross flow natural ventilation, with the potential to capture cool air at night for passive office cooling. Background ventilation is provided with the highest efficiency MVHR.

The walls, windows, floors, thermal insulation and Passivhaus ‘construction details’ together act as a system, to create an airtight building which requires virtually no heating at all!



As the developer of their own headquarters in Kettering, BSD made the decision to build an exemplar commercial office building, which could utilise leading edge design technologies and showcase their expertise as low carbon consultants.