Building designers and clients have a significant impact on the environment. We aim to make that impact as positive as possible by helping deliver high quality, low carbon architecture with high levels of internal comfort . Alistair is a Certified Passivhaus Consultant and can advise you on the solutions that best fit your brief and budget. We offer services from early stage low energy design review to a full Passivhaus consultancy service. We can also advise on reducing the embodied carbon of buildings using AECB PHRibbon software to inform smart building materials specification. Please contact us or email: if you wish to discuss how we can help with your project.

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We provide a full architectural design and energy modelling service to help you achieve high levels of comfort and energy efficiency on your project. We can advise at all stages of your project from concept design to on-site monitoring, both new build or refurbishment projects.  We can design ourselves, or support your architect providing low energy consultancy to ensure the design is as energy efficient as possible.

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We offer an architectural energy review service to help improve the efficiency of your new buildings or existing building stock. We are also able to provide low energy or Passivhaus consultancy as part of your design team set-up. 

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Both Henk and Alistair have extensive experience in educational design, with a focus on low energy. We can provide both full architectural design and energy modelling services. As well as saving on energy bills, Passivhaus school design provides a more comfortable environment which helps pupils maintain concentration levels throughout the school day. 

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We can advise and provide energy modelling to help you improve the efficiency and internal comfort of your exising or proposed buildings. We offer a flexible service tailored to your requirements, from concept design option appraisal using DesignPH software to full Passivhaus consultancy services using the Passivhaus Planning Package. We have helped projects gain planning permission through a focus on energy efficiency.

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If you don't have in-house energy expertise we can provide a low energy and Passivhaus design consultancy on your projects. From concept design option appraisal using DesignPH software to full Passivhaus consultancy services using the Passivhaus Planning Package, we can tailor our scope of services to meet your requirements.

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We can provide low energy design services at all stages of your building projects including construction stage review and monitoring. We can also work along side your design team in a design and build context, providing low energy consultancy to help ensure your projects are as energy efficient as possible.





Daylight and shadow studies can be used to assist complex planning applications, objections where there may be impact to right to light and to inform low energy design. (3).gif

To enable an accurate study, we develop a 3D model of the proposal and use GPS Co-ordinates and the sun's path at specific times of the year to illustrate the casting of shadows. Our dedicated software can then view the 3D model at any angle to specifically analyse the impact of shadows on your site or your neighbours.

The analysis allows us to understand the times of day/year when the proposal would benefit from increased/ reduced glazing.

The analysis can also be used to assess the efficacy of passive/ mechanical shading elements to improve glazing design and reduce overheating.

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Window area has been increased locally where needed, in order to compensate for the overshadowing from neighbouring dwellings, and to optimise solar gain.



Thermal imaging assessments can be used to identify if the existing envelope of a building has any areas of significant heat loss or  cold bridging which can lead to increased heating demand of the dwelling during the winter period as well as negatively affecting thermal comfort. We can also use thermal imaging for the monitoring of building details on site.

  • Identify areas of missing/defective insulation.

  • Identify thermal bridges.

  • Identify areas at risk from mould and condensation.

  • Identify water leaks in flat roof / building surfaces and other defects.

  • Identify air leaks in build-up.

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High heat loss gable eaves

Heat loss through cavity wall relatively even

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Heat loss greatest through windows


We use Therm software to model building junction details to identify and help design out potential thermal bridges.

  • Eliminating thermal bridges reduces the energy use of your building.

  • Eliminates cold spots, increasing indoor comfort.

  • Help Identify and remove areas at risk from mould and condensation.

  • Increase longevity of building components.

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