We are on our 4th Passivhaus and have built up a wealth of experience to tackle any design circumstances. Each of our Passivhaus designs have their own set of unique issues and characteristics which we will explore how they were resolved and became a fully-fledged building.
Passivhaus no.1 – Modern new build
Story: Our client recently purchased a detached property in a street of semi-detached houses and wished to demolish the building to build themselves a sustainable dwelling.
Issues: The council imposes a 45 degree light rule which is a method used by Local planning authorities to measure the impact from a proposal on sunlight and daylight to neighbouring properties.
Resolution: Together with the client, we collaborated on a building form that had chamfered edges to the rear conforming to the 45 degree light rule and a parapet frontage with recessed window frames for a sleek, modern, and elegant appearance.
Planning permission was successfully obtained and the Passivhaus began construction at the start of the year.
Passivhaus no.2 – Traditional new build
Story: Our client came to us with a building design that had already obtained planning permission for a pair of semi-detached houses. They decided that they wanted to go eco-friendly and sought our practice to assist in the next stages in design.
Issues: The original proposal was not designed as a Passivhaus. It had corbels, soldier & dentil coursing, and gables with a hip valley in the rear. As a general rule of thumb, the form of a Passivhaus should be as compact and simple as possible in order to achieve a low form factor which will affect the house’s efficiency in losing heat.
Resolution: We explained to the client step by step how we would alter the building to make it into a Passivhaus whilst retaining the architectural features. To make up for the inefficient roof shape we could install windows with a higher specification and use insulation with a lower u-value in the floors.
The project is now under construction and the building will aim to achieve the PHI Low Energy Building Standard. If we were involved with the design stages from the start, we might have been able to bring the energy standard of the building to a higher degree.
Passivhaus no.3 – Premium Passivhaus.
Story: Our client came to us with a wish to downsize from their current home and to build a new environmentally friendly forever home. The brief was to achieve the Passivhaus standard Plus or better, and to produce a layout that could encompass the later stages of their lives.
Issues: Set within a brownfield site, pre application advice was already sought and the Local Authority expressed their preference for a traditional design set back from the streetscape. The site area spans just over one acre and is enveloped by dense trees. Recent heavy precipitation has increased the flooding to the entrance.
Resolution:
- We produced a layout that was lifetime homes compliant with a bedroom and wet style bathroom accessible from the ground floor.
- The orientation of the building sits facing north to maximise the solar gains in the winter and positioned in the middle of the site to avoid the shade from the group of trees in the east.
- Veranda to shade the south facing elevation from summer sun.
- Rooflight incorporated to encourage passive stack cooling in the summer.
- Thermal mass added to bathrooms and ground floor.
- 2 no. solar thermal and 12 no. PV’s @ 45 degree pitch for maximum efficiency. 24 no PV’s @ 17 degree pitch.
- 225sqm ground source heat pumps.
- New lagoon to divert surface water run-off from heavy rainfall.
- We took inspiration from neighbouring and local characteristics to produce a design to complement the surrounding dwellings.
- Dense tree planting near the entrance to act as a buffer from the main road.
With the aid of a certified Passivhaus designer, we were able to produce a Passivhaus Pre-assessment study based on the current design and were able to achieve a Passivhaus Premium standard which is the highest standard achievable. The project is currently going into planning stage and if successful, it is believed that this may be the first Passivhaus premium dwelling of this kind in the country1.
If you would like to talk to us about reducing your energy bills, how to make your home more sustainable or building yourself a passive house, please feel free to call or email the office!
1It is understood that a college campus in Northern Ireland could be the first premium building, but this is not a dwelling.