Green Building Store is now 21°

Carntyne Church Passivhaus Flats, Glasgow

Shettleston Housing Association has just completed a newbuild 5-storey block of flats on the site of Cartyne Parish Church, aiming for Passivhaus certification.  

These homes were designed by Page/Park Architects, with John Gilbert Architects as the Passivhaus Designers, and were built by Stewart and Shields.

21°s ULTRA triple glazed timber windows and doors were specified for the project. Green Building Store also designed and commissioned the MVHR units at the project.


The 5-unit project was designed for over-55s clients, with the aim of creating energy effiicient and comfortable social housing. By aiming for the Passivhaus standard, the project sought to decrease fuel bills and make living in the new properties more affordable.

The building was constructed as a timber / steel hybrid structure and was implemented on site with a high degree of collaboration between design teams, and once certified, may become Scotland’s tallest Passivhaus. 

The building is not fully completed or certified at the time of writing, but the interim airtightness test result is 0.4 ach @ 50 Pa.

Triple glazed timber windows & doors

21°’s ULTRA range of triple glazed timber windows and doors were selected for the project. Tilt and turn and fixed windows were selected and finished in RAL 9003 white on the inside, and RAL 7037 on the outside. On the ground floor one ULTRA  entrance door was specified.  All ground floor windows and doors were Secured By Design compliant.

We looked at a wide range of suppliers. The ULTRA windows and doors stood out for us with their dual compression airtightness seals. Airtightness was obviously s incredibly important on this project, to ensure comfort of occupants and achieve the Passivhaus certification. We also liked the width of the ULTRA frame which enabled us to wrap 25mm of the frame in external insulation, enabling us to reduce heat loss. The supply and delivery of the windows all appeared to go smoothly and we have not had any complaints. The ULTRA triple glazed timber windows and doors on the project have been a great success, helping us achieve the airtightness and U values required for Passivhaus certification.

Christopher Antoniou- Architect at John Gilbert Architects

MVHR heat recovery ventilation

The MVHR systems for the flats were designed, supplied and commissioned by the Green Building Store to comply with the Passivhaus Standard and the Scottish Building Regulations. Spiral wound ducting was used to create a route and branch system incorporating silencers to keep the sound within comfortable limits. Each flat has its own unit in a cupboard which has several advantages over using a centralized system including cost saving and individual control. 

Project details


Page/Park Architects

John Gilbert Architects

Stewart and Shields



Case Study


Passivhaus certification

Still underway

Life changing homes