What is Passivhaus architecture?
The Passivhaus standard, which originated in 1980s Germany, aims to craft healthy and incredibly comfortable homes while consuming minimal heating and cooling energy.
Passivhaus sets a higher standard than the UK Building Regulations and proves its effectiveness in real-world scenarios. Often, there's a notable gap between typical UK-regulated design intentions and actual performance; this is not the case with a properly implemented Passivhaus.
As architects, after years of focusing on sustainable buildings, we've found that starting with the right design philosophy is key. We can then integrate additional technologies to help you achieve a carbon-neutral building.
Let's make a difference together.
1) Fabric First Approach
Passivhaus adopts the "Fabric First Approach" as a core principle, focusing on reducing heat loss in buildings through various methods:
High Levels of Insulation: Prioritising high insulation for walls, floors, and roofs keeps buildings warm, reducing the need for excessive heating.
High-Performance Triple-Glazed Windows: Triple-glazed windows of superior quality minimise heat transfer while maximising natural light entry.
High Levels of Air Tightness: Ensuring tight seals in the building envelope keep indoor climates stable, cutting down on heating and cooling energy use.
Minimising Thermal Bridging at Junctions: Careful design and construction techniques reduce thermal bridging, preventing heat escape through materials with high thermal conductivity.
Mechanical Ventilation Heat Recovery (MVHR): Incorporating MVHR systems efficiently exchanges heat between incoming and outgoing air, enhancing energy efficiency and indoor air quality.
2) Solar Orientation: Maximising the Natural Energy of the Sun
Solar orientation is a key aspect of sustainable building design. Here are some principles involved:
Majority of Windows Facing South: Strategically positioning windows to face south allows buildings to capture the low winter sun, maximising solar heat gain during colder months. This passive solar heating reduces reliance on heating systems.
Providing Shade: While south-facing windows benefit winter warmth, managing solar gains during the hot summer is essential. Shading elements such as overhangs, awnings, or deciduous trees help prevent overheating and excessive cooling demand. This approach maintains a comfortable indoor environment while minimising the need for mechanical cooling.
High Thermal Mass: Incorporating materials with high thermal mass, such as concrete, brick, or stone, helps stabilize indoor temperatures by absorbing and storing heat during the day and gradually releasing it at night. This minimises temperature fluctuations, enhancing comfort and reducing the reliance on active heating and cooling systems.
3) Renewable Technologies: Reducing Incoming Energy Demands
In pursuit of sustainable building practices, integrating renewable technologies is crucial in reducing incoming energy demands. Here's an overview of considerations:
Solar Energy: Solar power from photovoltaic (PV) panels is widely used. Installing solar panels can generate electricity for buildings.
Wind Energy: Wind turbines convert wind into electricity. Assessing wind patterns and space can determine turbine feasibility.
Heat Pumps: Heat pumps use ambient heat for heating, cooling, and hot water. Ground-source and air-source options are efficient, especially with renewable electricity.
Biomass: Biomass systems use organic materials for heat or electricity. Assessing feedstock availability and environmental impact is crucial.
Batteries: Energy storage systems, like batteries, enhance renewable energy reliability. They store excess energy for use during low generation or high demand.
4) Enhancing Biodiversity
Enhancing biodiversity on a site is essential for promoting ecological balance and supporting native flora and fauna.
Reviewing Appropriate Interventions: When aiming to enhance biodiversity, it's crucial to review a range of interventions suitable for the specific site context. This includes evaluating options such as green roofs, bird boxes, bat boxes, ponds, native planting, and habitat spaces.
Green Roofs: Vegetated roofs enhance buildings' appearance and provide habitats for wildlife. They manage stormwater runoff and enhance air quality.
Bird Boxes: Nesting boxes support bird populations, aiding biodiversity conservation by offsetting habitat loss.
Bat Boxes: Bat roosting sites aid insect control and plant pollination, particularly in urban areas lacking natural habitats.
Ponds: Creating water features supports amphibians, insects, and waterfowl, fostering biodiversity and plant diversity.
Native Planting: Native plants restore ecosystems, offering food and shelter for wildlife while requiring less maintenance.
Habitat Spaces: Dedicated areas like meadows or woodlands provide diverse habitats, supporting wildlife with food, shelter, and breeding sites.
5) Water Management
Managing water effectively is integral to reducing demand and mitigating potential flooding risks. By implementing thoughtful strategies, such as:
Low Flow Fittings: Installing low-flow fittings helps minimise water consumption without sacrificing functionality, promoting water conservation within your household.
Greywater/Rainwater Harvesting: Harvesting greywater and rainwater presents a sustainable solution for reducing reliance on mains water. These collected waters can be repurposed for non-potable uses such as irrigation or toilet flushing, further reducing demand on freshwater sources.
Balancing Ponds/Stores: Integrating balancing ponds or storage systems on-site serves to delay runoff, allowing water to be stored temporarily during periods of heavy rainfall. This helps alleviate pressure on drainage systems and reduces the risk of flooding downstream.
Permeable Surfaces: Utilising permeable surfaces, such as permeable paving or gravel, allows rainwater to infiltrate the ground rather than contributing to surface runoff. This not only helps to replenish groundwater supplies but also reduces the strain on drainage infrastructure.
Ready to do something amazing with your new house?
Consider a Passivhaus! It takes care and attention to detail, but the concept is pretty simple. As your architects, we're here to help you every step of the way. With lower energy consumption and healthier, more comfortable spaces, you're not just building a house – you're helping to make a better future.
Let's make a difference together.