Sustainable Design

At Stride Treglown, as designers, we recognise that we have a responsibility - and importantly an opportunity - to make a positive contribution to the environment through the buildings and places that we create.

Therefore we approach each project with a view to maximising the possibilities for environmentally-considered design, which is essentially just ‘good design’. This approach need not necessarily make designs more expensive, and in fact often saves them money in the longterm, but has the power to inspire, inform and make genuine improvements to our environment and quality of life.

This means we seek ways to limit any potentially negative environmental impact that our designs may have in terms of carbon emissions, pollution, resources, waste or ecology. But at the same time actively exploring opportunities for them to have a positive impact; through re-use, regeneration, using sustainable forms of energy and promoting community, wellbeing, sustainable travel, biodiversity, beauty and delight.



We also offer the following specialist sustainable design services:


Passivhaus is a tried and tested design principle based on the core ethos of achieving a healthy, comfortable and stable environment for end users driven through the control of air quality.

The concept focuses on reducing the requirement of energy use in the first instance, rather than the generation of a higher energy demand through renewables. It is a robust and effective way to achieve the challenge of carbon reduction for the built environment sector.

Passivhaus is an exacting quality assurance process giving the client confidence in the built performance from an early stage. The closely monitored design and build process ensures reduced heat loss through the building fabric, resulting in greatly reduced space heating demand throughout the year.

Stride Treglown have in-house Certified European Passivhaus Consultants/Designers providing expertise in designing to Passivhaus standards. The service provides guidance, advise and assessment for all types of buildings for both principle and certification standard.

Sustainable Design Projects

Applied Research and Development
Civic, Community and Culture
Hotels and Leisure
Non-urban Living
Office and Workplace
Owner Occupier
Public Clients
Research and Incubation
Student Living
Sustainable Living
Technology and Innovation

Sustainable Assessment

Stride Treglown has a dedicated team of assessors who are trained and licenced to undertake and provide advice regarding a large range of sustainability assessments and evaluations. Early advice and input by our assessors contributes to the delivery of cost effective and deliverable sustainable solutions.

Our Cardiff office that we designed is carbon neutral and the first privately funded office scheme in the UK to achieve a BREEAM ‘Outstanding’ score in its post construction certification.


Assessment and evaluation services we provide include:

* Building Research Establishment’s Environmental Assessment Method      * Defence Related Environmental Assessment Method

Passivhaus Planning Package (PHPP) Assessment

Passivhaus Planning Package is a proven tool used to assess the energy efficiency of a building through the conventions of the Passivhaus principles. Stride Treglown can review a building at design stage, pre or post planning in order to measure the building for potential Passivhaus certification. All types of building can be assessed through PHPP from private housing to schools and commercial premises. The PHPP process will identify the heating and cooling demand per year as well as the renewable energy demands and gains which can provide the client with a good estimate of annual running costs. As part of the Passivhaus services offered, design stage thermal modelling can be incorporated to ensure low thermal bridging values and reduce the performance gap seen in more traditional build types.Stride Treglown offers an assessment report post PHPP which provides both the results of the assessment and suggestion for improvement or alternative routes to achieve certification standard. PHPP can also be used to assess a building to AECB Carbonlite Silver Standard which has a relaxed standard to the full Passivhaus Certification.

Standard Assessment Procedure (SAP) and EPC, Residential

Standard Assessment Procedure are calculations undertaken through the government approved modelling software which measures the energy efficiency of buildings in compliance with Part L1A Building Regulations. Stride Treglown undertake SAP calculation for small or large scale new build residential developments providing SAP reports for both design stage and final completion, including generation of EPC certification to satisfy Building Control. Stride Treglown can produce all auxiliary information required for SAP assessment including U-value calculations, thermal modelling if necessary and technical advice on performance improvement.

Thermal Bridging Analysis

Considering thermal bridges are an important part of sustainable design. Heat lost through poorly designed bridges can make a significant difference to the overall efficiency of the building. There are two types of thermal bridging, construction thermal bridging where materials with high conductivity penetrate the insulation layer, and geometric thermal bridges, where the insulation changes in direction or thickness.Thermal bridge analysis calculates the heat lost in addition to the normal thermal transmittance value of the element. By calculating the thermal bridges it not only provides a greater accuracy in calculating the in-use energy of a building, helping to close the energy performance gap, but also provides a base to improve detailing by identifying the worst performing junctions.Both SAP and Passivhaus require thermal bridge calculations. Stride Treglown offer both 2D and 3D thermal bridge analysis providing psi (Ѱ) values for use in the overall energy efficiency assessment of a building.

Post occupancy evaluation

Other Sustainability Services

Our Clients

  • Aberdeen Asset Management
  • Abertawe Bro Morgannwg University Health Board
  • Airbus
  • Amec
  • Arena Seating
  • Associated British Ports
  • Balfour Beatty
  • Barclays
  • Barratt Homes
  • Bettws Boys and Girls Club
  • Bloor Homes
  • BNP Paribas
  • Borough of Poole Council
  • Bournemouth University
  • Bouygues Construction UK
  • Bristol City Council
  • Bristol International Airport
  • Brymain Investments
  • Cardiff and Vale University Health Board
  • Cardiff Bay Retail Park Trust
  • Carmarthenshire County Council
  • Castlemore Securities
  • Chichester College
  • City and Council of Swansea
  • Cornwall Council
  • Dorset County Council
  • DWP
  • Eastleigh Borough Council
  • Ernst and Young
  • Exeter College
  • GE Aviation
  • GE Healthcare
  • Hafod Housing Association
  • Hallam Land
  • HCA
  • Health and Safety Executive
  • Hemsley Fraser
  • Hendre Housing Association
  • ISG Construction
  • Kier Group
  • Kingfisher Housing
  • Laing O'Rourke
  • Lend Lease
  • Linden Homes
  • Martock Parish Council
  • Midas Construction
  • Ministry of Defence
  • Ministry of Justice
  • Morgan Sindall
  • MRW Building Services
  • National Composites Centre
  • Neath Port Talbot County Borough Council
  • North Bristol NHS Trust
  • North Somerset Council
  • Parkhall Estates
  • Persimmon Homes
  • Plymouth City Council
  • Plymouth Hospitals NHS Trust
  • Reynolds Porter Chamberlain
  • Rhondda Cynon Taf County Borough Council
  • Rockspring
  • Rowan Properties Partnership
  • Royal Agricultural Association
  • Royal Devon and Exeter Hospital
  • Royal Devon and Exeter NHS Foundation Trust
  • Royal Holloway, University of London
  • Royal Masonic Benevolent Institution
  • Sainsbury’s
  • Saracens
  • Schroeder Asset Management
  • Sedgemoor District Council
  • Somerset County Council
  • South Somerset District Council
  • Sovereign Land
  • Stride Treglown
  • Sustain
  • Swansea University
  • Taylor Wimpey
  • Terrace Hill
  • The University of Exeter, on the University’s Cornwall Campus
  • Torbay Council
  • Torfaen County Borough Council
  • Unite
  • United Welsh Housing Association
  • University of Bristol
  • University of Chichester
  • University of Plymouth
  • University of the West of England
  • URS
  • Vinci
  • Virgin Media
  • VOSA
  • Warings
  • Wessex Water
  • West Berkshire Council
  • West Sussex County Council
  • Westerleigh Group Ltd
  • Willmott Dixon