Clay Architecture sustainable design principles

Our sustainable design principles are straightforward and balanced and can be incorporated into any construction project, including new build housing.

We are passionate about sustainability and have been delivering sustainable design ever since we completed our very first project, Faversham Gym Club in 2003. We improvised a workable passive-stack ventilation system as an alternative to air conditioning, using off-the-shelf motorised industrial louvers for the gymnastic hall because there were few specialist products available at the time.

Over the years we have incorporated elements of sustainable design into a wide range of projects, including school buildings, libraries and commercial properties.

Many of these projects involve the refurbishment or extension of older properties, some with historic significance, some of which are listed. You have to be flexible and innovative when adapting an older building. And that should include the flexible and innovative application of sustainable design wherever possible.

With new build projects there is more scope to deliver a fully integrated sustainable design from inception. Even if only a partial application of sustainable design is viable or appropriate for a new build project, it always pays to look at a project holistically.

We don’t sell sustainable design to our clients because it’s an everyday part of our working process. Many clients want to incorporate at least some aspect of sustainability into their projects, whether it is to reduce their fuel bills, to improve their chances of planning approval, or to do their bit for the environment.

All this work – plus our interest in and study of vernacular, agricultural, industrial, tropical, and historic buildings – has led to a set of sustainable design principles.

So, what are our sustainable design principles?

1. Find the appropriate level of sustainable design – partial or full, low-tech, or hi-tech
2. Ensure the project is viable
3. Maximise the use of natural light
4. Manage solar heat gain to avoid overheating in Summer
5. Use thermal mass with night cooling strategies to improve thermal comfort
6. Use natural or passive-stack ventilation
7. Create healthy acoustics in and around a building
8. Incorporate sustainable drainage systems to mimic natural drainage where possible
9. Promote health and well-being through building design
10. Encourage and improve biodiversity through building design
11. Consider embodied carbon alongside the carbon footprint
12. Use local knowledge, skills and materials where possible
13. Encourage regeneration, adaptive reuse of older properties and the use of brownfield sites
14. Collaborate with experienced and knowledgeable sustainability specialists
15. Educate our clients but also be pragmatic and responsive to their needs

Clay Architecture’s sustainable design principles applied to homes

We want to apply our sustainable design principles to the delivery of good quality custom homes, home for self-builders and housing schemes for small to medium sized developers.

Working with a sustainable lifestyle developer for over three years, we helped to develop a concept for a prototype ‘eco-house’ to their brief. Although this project did not proceed due to lack of funding, we are confident that features from this ‘eco-house’ concept will be incorporated into our future residential projects.

The house will be built of timber and a combination of pre-cast and site-cast Hempcrete, a composite material made from wet-mixing hemp shives with a lime binder. Hemp is a fast-growing crop that absorbs a very high-level of atmospheric CO2 as it grows. The production and application of Hempcrete is relatively low-tech and uses very little energy. It is a better-than-zero-carbon building material. When combined with lime render, hempcrete provides a natural, vapour-permeable, hygroscopic, airtight insulation material with great thermal mass. This is the ability of the mass of a building to absorb and store thermal energy, which serves to even out daily and seasonal temperature fluctuations. Natural and passive stack ventilation allow the house to breathe naturally, using the effect of wind and buoyancy to drive fresh air through the house and minimising the need for mechanical ventilation. The high thermal mass of the house combined with the natural and passive stack ventilation system enables night cooling – the purging of excess heat and the cooling of the building fabric at night. This reduces peak daytime temperatures inside the house by as much as 2o to 3o.

These features can be adapted to fit different needs, sites, and contexts and a tailored home design can be developed. The parameters of each home design will be tested and adjusted using Dynamic Simulation Modelling to achieve optimum performance. The end result will be a home that performs comfortably in terms of temperature, airflow, and light, even if it was to be disconnected from all active energy sources. Once the design parameters of the home have been optimised, other systems can then be calibrated and added as needed to enhance performance, such as photovoltaic roof tiles to generate electricity, and or an efficient heating system appropriate for the situation.

Clay Architecture’s sustainable design principles applied to school buildings

We apply our sustainable design principles to all our school projects, the most fully integrated of which was a new build 1 FE replacement school building for Walderslade Primary School in Chatham, Kent. The key features of this school are:

Acoustically attenuated passive stack ventilation with night cooling, rated ‘Very Good’ by BREEAM. Large roof lights and north-facing windows provide good quality natural light to the single-aspect building cut into the hillside. High g-value glazing and automated blinds to south-facing roof lights to reduce solar heat gain. 164m2 of photovoltaic roof panels to reduce carbon footprint by 23%. Fully automated lighting system.

This project won a Kent Design & Development Award and a retrospective Medway award for best school building completed in the last decade.

Conclusion

Clay Architecture’s sustainable design principles can be adapted to suit all project types, from housing to schools. We believe there is no one-size-fits-all approach to the sustainable design of buildings. The right solution for each project should be tailored to fit the brief and take into consideration the site, local context, climate, geology, topography, resources, infrastructure, budget, viability, and other factors unique to each project.