11 things we consider when designing an eco home

A good eco home isn't a matter of bolting on green features. It comes from a set of decisions made in the right order, from the orientation of the building down to the last junction.

Whether we are retrofitting a terrace or designing a new house in the countryside, these are the eleven things we work through on every low-energy project.

A low-energy rural home designed on Passivhaus principles, with careful solar orientation, natural materials and a close connection to its setting. RISE Design Studio.

1. Design with the climate and site

Every site tells you something, about sun paths, wind direction, local materials and the lie of the land, and the first job is to read it. Shaping the building to its site, getting the orientation, solar access, shading and ventilation right, reduces the energy it needs from the very start. Get those basics right and much of the rest follows.

2. Passivhaus precision

We use Passivhaus principles to guide thermal comfort, airtightness and performance, whether or not a project certifies to the full standard. In practice that means super-insulated walls, triple-glazed windows, mechanical ventilation with heat recovery, and meticulous detailing to remove thermal bridges. Even used informally, the Passivhaus method raises the bar well above the regulations.

3. Natural ventilation

Summer comfort without air conditioning is entirely achievable, and it starts with air movement. Cross-ventilation, the stack effect, and operable windows in the right places can cut overheating sharply. It isn't guesswork: where the openings go, and how air moves through the plan, is designed deliberately from the start.

4. Airtightness, with ventilation

Airtightness has a bad reputation it doesn't deserve. Paired with MVHR, it is what gives you fresh, filtered air and very low heat loss at the same time. The two go together: seal the building properly, then ventilate it deliberately. We test the envelope carefully, because every leak wastes energy and comfort.

5. Low-embodied-carbon materials

Timber, cork, lime, clay, straw. These aren't a passing trend; they store carbon, regulate humidity and age well. Every material in a RISE home has to earn its place on performance, ethics and how long it will last. We are wary of greenwash, and always favour what is genuinely low-impact over what is merely marketed that way.

6. Thermal logic, and U-values

We pay close attention to U-values, not to tick a target but to make sure a house holds its warmth in winter and stays cool in summer. That means insulating deeply, but also intelligently, so the building feels good to be in all year. On a retrofit we often use external insulation, which keeps the thermal mass of the existing walls working for you and avoids the damp problems internal insulation can cause.

7. Daylight, air and good space

A low-energy home shouldn't feel like a bunker. The best ones feel light and uplifting, because daylight, views and the flow of the plan have been designed in from the start. We tend to put the active, lived-in rooms to the south where the light is best, and the quieter service spaces to the north.

8. Reduce the operational energy

The less energy a house needs, the easier it is to supply cleanly. So we start by cutting demand, then meet what is left efficiently: LED lighting and efficient appliances, an induction hob, solar panels and battery storage, and a ground or air source heat pump. None of it is a gadget for its own sake; each part earns its place in the overall energy strategy.

9. Use water carefully

Water is easy to overlook and worth designing for. We build in rainwater harvesting and greywater reuse where it is practical, and low-flow taps and dual-flush toilets come as standard. On the right site we will look at reed beds and natural treatment too. The invisible parts of a home, the pipes, tanks and filtration, matter as much as the visible ones.

10. Design out waste

Construction waste is one of the biggest environmental costs of building, so we reuse what we can, specify responsibly, and design with disassembly in mind. The useful question is how the building will come apart in a hundred years: whether its parts can be reused or returned to the ground rather than sent to landfill. The same thinking extends to the garden, which can be somewhere to grow, rest and gather rather than just a lawn.

11. Design for change

The most sustainable house is one that stays useful for decades, which means designing for adaptability. Can the layout flex as a family's needs change? Can rooms serve more than one purpose? Can new technology be added later without tearing things apart? Building that flexibility in from the start is what keeps a house from becoming obsolete, and keeps it out of the skip.

None of these is exotic. Taken together, and applied from the first sketch rather than added at the end, they are what makes the difference between a house that looks sustainable and one that genuinely is, in every material and junction. If you are thinking about a new low-energy home or a retrofit and want to get the fundamentals right, we'd be glad to talk it through.

→ Email us at architects@risedesignstudio.co.uk
→ Or call the studio on 020 3947 5886

RISE Design Studio, Architects, Interior Designers + Sustainability Experts

☉ Architecture for people and planet
☉ Trading since 2011
☉ Company reg no: 08129708
☉ VAT no: GB158316403