Marigold care home blooms in Bedfordshire

Marigold House in Leighton Buzzard is a 63-place care home for older people targeting the Passivhaus standard. Developed for Central Bedfordshire Council, the accommodation is organised as a cluster of small households across three floors, each with a dedicated living & dining area. A day centre providing care and support for around 25 older people living in the community is co-located at ground floor level.

Central Bedfordshire Council has embarked on an ambitious programme for its senior living provision with - not one but two - projects targeting the Passivhaus standard currently under construction. The Marigold Care Home and the Red Kite Meadow development projects utilise two different construction techniques and airtightness strategies, each with their advantages and disadvantages. An additional two Passivhaus homes are in the pipeline for completion in 2027-8 and will carry forward the best construction characteristics and airtightness strategies from the current two pilot projects.

We are investing in building contemporary living places to ensure that older people have access to a better choice of accommodation, using Passivhaus certification to deliver low energy buildings with much improved indoor air quality, prioritising the health and well-being of residents, staff and visitors.

Ian Hanton, Development & Commissioning Manager, Social Care & Housing, Central Bedfordshire Council

Specification of Passivhaus for the project also aligned with the Council’s Sustainability Plan. The business case for targeting the Passivhaus standard for the project was based on assumptions of savings on operational energy consumption which more than justified the additional investment in improvements to the building fabric and certification, with a break-even point anticipated after 16 years. This calculation may need to be amended in the light of recent energy price volatility, further strengthening the case for the council's commitment to Passivhaus.

Marigold House, Leighton Buzzard. Image credit: Central Bedfordshire Council

Key stats

Construction: Steel frame, block and brick
Number of homes: 63 bedrooms
TFA: 3,591 m²
Build start date: 2021
Completed: Under construction
Certified: Targeting Passivhaus

Construction

Marigold House is being constructed on traditional brick and block construction, with the airtightness line on the internal face of the blockwork wall. Building Information Modelling (BIM) is being used throughout the design, to deliver an innovative and accurate design.

U-values

Marigold House, Leighton Buzzard. Image credit: Central Bedfordshire Council

Floor: 0.09 W/m²K

Insulation over beam and block

Wall: 0.17 W/m²K

Block & brick

Roof: 0.13 W/m²K

Tapered insulation & single ply membrane

Building performance

Designed energy performance

Space Heating Demand (≤ 15 kWh/m².a)

9 kWh/m².a

Heating Load (≤ 10 W/m²)

8 W/m²

Primary Energy Demand (≤ 120 kWh/m².a)

145 kWh/m².a

Primary Energy Renewable (PER) Demand (≤ 60 kWh/m².a*)

61 kWh/m².a

Primary Energy Renewable Generation

18 kWh/m².a

*+/-15 kWh/m².a allowance if offset by energy generation. See Passivhaus criteria.

Services

Heating is provided by air source heat pumps. Summer comfort strategies include solar canopies and brise soleil to bedrooms and living spaces at risk of excess solar gain.

Passivhaus design of Marigold House was a client-led decision, the first new care home we’ve built in nearly 50 years, driven by a vision to futureproof our next generation of facilities that enable high quality, energy efficient later living in Central Bedfordshire.

Ian Hanton, Development & Commissioning Manager, Social Care & Housing, Central Bedfordshire Council

Key team

Client: Central Bedfordshire Council
Architect, M&E Consultant, Structural Engineer: Concertus Building Design Consultants
Passivhaus Designer/ Consultant: QODA Consulting
Contractor: Farrans Construction
Passivhaus Certifier: Mead Consulting

Breaking ground at Marigold House. Image credit: Central Bedfordshire Council

It is great to see such informed and ambitious clients who understand the benefits of building resource-efficiently, the benefits to its immediate occupants, and the positive societal impacts it delivers. We look forward to seeing the scheme complete later this year.