Goldsmith Street delivers economies of scale

The award winning and Stirling Prize nominated Goldsmith Street development for Norwich City Council, just shy of 100 Passivhaus homes that are 100% social housing, has recently achieved certification. Consisting of 93 Passivhaus homes spread across 7 blocks aligned in 4 simple rows the development now holds the title as the UK's current largest residential Passivhaus development.

Goldsmith Street aerial view ©Mikhail Riches/John Fielding aerial photography

Goldsmith Street aerial view © Mikhail Riches/ John Fielding aerial photography

The terraced housing scheme began life as an RIBA competition (won by Mikhail Riches with Cathy Hawley) in 2008. The competition-winning Goldsmith Street design did not aim for Passivhaus standard at the outset. The council’s subsequent conversion was sparked by two local housing association projects in north Norfolk, and adopted a fabric first framework.

Passivhaus is a good way of building because it both helps with fuel poverty and is aligned with our climate change agenda through carbon emissions reduction.’

Andrew Turnbull, senior housing development officer, Norwich City Council

All the new council-owned energy-efficient homes, a mix of 2-4 bed houses and 1-3 bed flats, will be let for social rent through Norwich Home Options.

Goldsmith Street, Street section

Narrow streets, carefully considered window placement, and cleverly sloped roofs maximise daylight into a dense developement, that does not feel oppresive or unsafe. Parking has been pushed to the perimeter to help maintain openess.

Key Stats

Treated Floor Area (TFA): 3,337.7m²

Year of completion: 2019

Units: 93 certified Passivhaus homes

Construction cost £14.7 million

Construction cost per m² £1,875 (excluding professional fees)

Goldsmith Street Mikhail Riches/ Tim Crocker

It has been fantastic to meet some of the residents and hear their stories, which have shown the real difference these new homes will make. This development demonstrates our commitment to providing high quality social housing and I’m especially proud of these properties’ eco-credentials which will benefit residents as well as the environment.

Cllr Gail Harris, Norwich City Council

This project demonstrates that cost is no longer a barrier; at £1875 / m², construction costs are in line with the average for the country. Architect Mikhail Riches explains that cost savings were made early in the design process by making significant alterations to the brickwork, roof and foundation packages, which didn't affect energy performance. The savings made in other areas allowed the Passivhaus features to be safeguarded. That is not to say that this is a low spec development. Contemporary materials include black glazed pantiles traversing from roof to wall, contrasting light coloured brick, and perforated metal brise soleil.

Predicted Energy Performance

	Airtightness (≤0.6ACH@50pascals)	0.55-0.61
	Thermal Energy Demand (≤15kWh/m².yr)	11.7-12.3
	Thermal Energy Load (≤10W/m²)	10
	Primary Energy Demand (≤120kWh/m².yr)	109-117

This is Mikhail Riches's first Passivhaus project and they had high architectural expectations. The architects wanted the Passivhaus Standard to work to the design rather than the design being secondary to complying with the Passivhaus Standard.

I think that’s where a lot of Passivhaus schemes fail,” adds Turner. “The focus is often too much on making the project Passivhaus compliant and forgetting that there still needs to be good design. This is where we pushed the design hard to achieve both.

James Turner, Mikhail Riches

This has been reflected in the finished result with services concealed and elegantly integrated into the design. Gas meter cupboards are concealed, gas pipework is hidden within the cavity of the brickwork, MVHR intakes are intelligently controlled, and boiler flues are not visible from the street.

It had to be ensured that systems & services employed were accessible and maintainable by the Council so they could readily adopt the new buildings with little issue. Each dwelling has a range of providers’ services pre-wired, so that they can be connected on demand, mitigating the need for service providers to come in later and unintentionally damage or drill through vital airtightness layers.

Key lessons learned

1. Have an aspiration & commitment to achieve Passivhaus from the outset

2. Manage solar gains & overshadowing carefully

3. Early service co-ordination essential to integrate into design

4. Careful selection of construction method – to ensure repeatability

Key Team

Client: Norwich City Council

Architect: Mikhail Riches

Contractor: RG Carter

M&E engineer: Greengauge

Passivhaus consultants: WARM

Clerk of Works: Enhabit

Quantity Surveyor: Hamson Barron Smith

Structural Engineer: Rossi Long Consulting

Timber frame: Cygnum Timber Frame

MVHR supplier: Green Building Store

Certifier: Etude

Goldsmith Street Mikhail Riches/ Matthew Pattenden

Given that the upcoming Future Homes Standard is likely to increase regulations to the equivalent of Passivhaus certification within the next few years, good coordination and collaboration are key drivers of successful delivery. Goldsmith Street demonstrates all the positives that can be achieved when everyone involved pulls together in the same direction.

Learn more about delivering Passivhaus to the masses at the 2019 UK Passivhaus Conference this October in Manchester. Exclusive discounts are available for those working in Local Government & Housing Associations.