SOLAR POWERED ANNEXE
ENFIELD 2023
●THE AMOUNT OF POWER GENERATED BY THE SUN HITTING THE EARTH IN ONE HOUR IS MORE THAN THE ENTIRE WORLD CONSUMES A YEAR.
In this article you’ll learn how this customer harnessed the Suns awesome power, integrating solar with modern methods of construction to build a tasteful contemporary annexe. Having delivered hundreds of projects across the U.K. this is one of the most interesting we have handed over.
Let’s shine some light on the details.
MULTIGENERATIONAL ANNEXE LIVING
Based in Edinburgh teaching art, the distance from his daughters house was a major barrier to their relationship. Grand children on the way and with a beady eye on old age, both decided that relocating and building an annexe was the perfect solution.
Their design ambitions were non negotiable, under no circumstance would they build a twee / stereo type annexe. This was to be a life affirming lifestyle change and the annexe needed to embody this.
● DESIGN BRIEF
Our clients wanted something contemporary and tasteful. It might be a granny annexe but they wanted to break from convention, and create something unique in its own right, with wow factor and kerb appeal. Taking this onboard, the client appointed architect developed a one bedroom annexe with a large open plan kitchen, bathroom and art studio. Using an L’Shape arrangement to create a private courtyard, capture the country views and ensure the solar panels were in the optimum position.
When specifying solar there’s alot to consider, the siting of them being one of the most important surprisingly ‘as much as 40 percent of potential solar generation can be lost due to shading’.
● INSULATION
Having lived on Scotland where the building regulations are more rigorous than in England, our customer wanted to translate his knowledge into the London based Annexe. Combining SIPs panels for the walls and roof, with a joisted celotex insulated floor, triple glazing and additional 30mm insulated plasterboard, the U’Values far exceed current building control requirements.
U-values (sometimes referred to as heat transfer coefficients or thermal transmittances) are a measure of how effective the elements of a building’s fabric are as insulators. That is, the degree to which they prevent heat from transmitting between the inside and the outside of a building.
The lower the U-value of an element of a building’s fabric, the more slowly heat is able to transmit through it, and so the better it performs as an insulator.
●SOLAR
A 6kw system with batteries and inverter was installed. With a flat roof you cannot penetrate the rubber membrane, otherwise leaks will ensue and warranties will be voided. To anchor the panels ballast was used, the additional weight calculated by the structural engineer for specification of the roof structure. The high performing thermal envelope meant that a 6kw system was more than enough for single occupancy.
●GROUND WORKS
It’s not uncommon to come across clay soil in London. In this case, the clay had a high shrinking factor with many large Oak trees nearby. To overcome this, piles were driven 12 meters into the ground, which is unusually deep. In most cases water & power supply comes from the main property. In this case, power and water were independent. Waste water and soil was gravity fed into the existing system.
●HOT WATER
Using the FlexTherm Eco thermal charging station, which converts electricity directly into heat and, stores it for the provision of hot water and, combined with the solar system enable hot water to be supplied CO2- neutral. The appliance is clean and environmentally friendly as it does not burn any gases, contain any toxic substances, and is 100% recyclable. Only a water and electrical connection are required, it contains no moving parts, and the battery needs little maintenance.
●EXTERNAL PRECISION
Using burnt Japanese pine, with insect mesh behind, the vertical cladding was installed running the entire height and in complete widths, creating a uniform pattern across the elevations. These small details, take something from good to excellent. Mixing the roof forms made the building architecturally interesting, across the flat roof 12mm EPDM was installed and raised seam zinc on on the mono pitch. Large format triple glazing was sited for light and a medley of views.
●INTERNAL SIMPLICITY
With a considered collection our client did not want the interior to distract from their art works. Engineered oak was used throughout, white washed walls, feature lighting, loads of natural light and wonderful views gave a feeling of space and calm.
Howdens kitchen, Grohe taps, Bette and Duravit sanitary items with concealed cistern were used in the kitchen and bathroom.
●BUILD
Timber frame was supplied by Building With Frames along with all other materials. ANX supplied all the trades required to complete every element of the build.
SERVICES ENGAGED
Building Control | Mobilisation | Ground | Joinery | Electrical | Decoration | Kitchen | Plumbing | Solar | Commissioning | Landscaping.
Planning and building control approved the result was stunning. Sympathetic to the open countryside and achieving the clients ambitions, their family are the proud owners of a timeless building that all generations can enjoy.
If you want to be the architect of your dream build, then please get in touch.