The eight strategies in the Communion Sustainability & Energy Creed help bring a focus and rigour to our thinking around sustainability, no matter the size or type of project we’re working on.
Some projects, usually new build dwellings, are able to achieve all eight goals.
Other projects, usually building extensions and refurbishments are much harder to fit into the framework.
Upper Lodge on the Kentchurch Estate is one project where we had to be quite flexible in how we applied each of the eight strategies. It is a stone-built property that was originally one of the outbuildings for Kentchurch Court, but was converted to a dwellinghouse in the 18th century.
Here is how we applied each of the strategies in the Creed for the building.
Fabric: Prioritise the Use of Passive Measures
We prefer passive measures that reduce the amount of energy required to heat a home over active measures that need energy to operate and will require periodic replacement.
For Upper Lodge we designed internal wall insulation using low density wood fibre boards, typically 60mm thick. This was applied to the bare stone walls, then covered with a breathable lime plaster.
This ensures the existing stone walls are able to breathe as they were originally intended, but also provides much improved thermal performance of the building envelope.
Orientate – Make the Most of Free Energy from the Sun
We look at the location of rooms and consider the direction they should face. Our aim is to make the most of solar gain in winter and prevent overheating in the summer. While we couldn’t change the orientation of Upper Lodge, we could change the location of the rooms within the building.
Swapping the lounge and kitchen provided a more fluent use of the ground floor. The kitchen/diner now extends out into the secluded rear garden. The lounge sits on the south side of the floor plan, creating a much more comfortable space and providing some much-needed warmth in the winter months.
Air-Tight – Reduce Draughts and Unwanted Air Movement
We aim to eliminate unwanted air movement between the outside and inside of a building. This removes the need to heat or cool that air, which is ultimately a waste.
Nobody can claim that a stone building will be totally air tight. However, in Upper Lodge, we reduced as much unwanted air movement as possible.
We replaced single-glazed window casements for double-glazed replacements, improved seals around doors and windows and made sure services apertures were correctly sealed.
This has significantly reduced the space heating requirements for the dwelling.
Ventilate – Extract Stale Air and Supply Fresh Air
Buildings that are too airtight affect the health and wellbeing of its occupants. We use efficient ventilation systems that extract stale air and supply fresh air.
In Upper Lodge, we created concealed building voids and various routes through the internal fabric of the building so we were able to install a mechanical ventilation with heat recovery unit. This removes stale air from ‘wet’ areas of the dwelling, recovers the heat, then pre-heats fresh air into the dry areas.
The system runs at a very low speed and indiscernible sound levels all the time, boosting up to a higher ventilation rate when the unit senses a higher humidity, such as when a shower or bath is in use.
Shade – Prevent Overheating from the Sun
We assess the need for shading to prevent a building from overheating in the summer while also allowing warmth from the sun during the winter months.
Upper Lodge has 450mm thick stone walls and relatively small windows on the south side. The building’s listed status meant we couldn’t make these windows any larger, so the energy gain from the sun was fixed.
However, the smaller windows prevent most of the overheating issues, while solar control glass reduces overheating to an acceptable level.
Control – Provide Easy to Operate Systems
We want our clients to be able to actively engage with the energy usage of their building. We therefore aim to install controls that are easy for them to operate.
In Upper Lodge, we installed Heatmiser underfloor heating controls throughout the ground floor, with a Nest smart learning thermostat controlling the first floor. Both systems are app-based, allowing the owner easy access to all the heating settings.
Monitor – Recognise that Knowledge is Power
The more we know about a building’s energy usage the more we can reduce it.
Upper Lodge is fitted with energy meters on the highest consuming items and circuits. This enables the owner to monitor energy consumption and can feed into occupancy and usage patterns for the dwelling.
Report – Accelerate the Learning Process
We monitor the energy usage of our buildings for the first year of their occupation. We then carry out a final inspection where we record meter readings and check all systems are operating as intended. This data is then anonymised and sent to RIBA.
In the case of Upper Lodge, this will help inform other professionals dealing with similar stone buildings – helping to ensure continuous improvement and an enhanced understanding of what it takes to create buildings that are fit for the future.
