Case Study
Name of Case Study: Increasing Offsite Construction for Housing in Scotland
Country: Scotland
Partner: Built Environment – Smarter Transformation
Company: Link Group Ltd & Paragon Housing Association
Link to Website: https://linkhousing.org.uk/
https://paragonha.org.uk/
Overview / Project Summary:
The Alva Volumetric Housing Development is a turnkey development for social rent in
Alva, Clackmannanshire, Scotland, is Scotland’s first volumetric off-site manufactured
housing development built to the Gold Standard of Sustainability.
The development comprises a mix of one-bedroom cottage flats, and two and
three-bedroom homes. Following completion, 14 units were transferred to Paragon,
while Link retained ownership of the remaining 34 units.
Multimedia Content:
Description:
A housing development for Link Group Ltd and Paragon Housing Association at Queen
Street, Alva, Clackmannanshire was officially opened in 2018 and was the first
development of its kind in Scotland.
The £5.3 million construction of 48 homes for social rent was supported by a grant of
almost £3.1 million from the Scottish Government and is a showcase of how offsite
construction can more readily deliver high quality, affordable, energy efficient homes.
The development was an exciting and innovative project, producing energy efficient
homes which offer real benefits for the tenants, and also help the social housing sector
grow and develop its knowledge around the use of the volumetric construction
techniques. A lot has been learned about these more affordable and sustainable homes,
and the lessons learned will shape the development of the next generation of houses.
The Innovation
The 48-unit project was Scotland’s first offsite, volumetric manufactured housing
development built to meet the Gold Standards of Section 7 Sustainability as outlined in
the 2016 Scottish Building Regulations.
Some other innovations included in the development were the integration of Mechanical
Ventilation and Heat Recovery (MVHR), heat pumps and solar photovoltaic (PV) panels.
Key Outputs
The majority of the volumetric homes had their entire interiors constructed offsite, fitted
out with tested services, kitchens, bathrooms, toilet and wet rooms and were fully
decorated.
The Alva project demonstrated that with appropriate quality control, the volumetric units
could be constructed in reduced time in the factory. In this project a 16-stage production
line was set up, where the modules progressed each day to the next station.
The project also demonstrated that rapid installation of the modules on site was possible,
with module landings taking on average approximately an hour per module.
Overall, it can be said that the use of volumetric timber construction has simplified
several key project aspects. The quality control opportunities in the factory resulted in a
product with predictable quality and cost, both factors being crucial for affordable
housing providers.
Challenges
The modules were sourced from Wales, which resulted in the crossing of 3 road
legislative systems for each module delivery which created a number of logistical
challenges.
Another challenge, common to many innovative construction projects, was managing the
supply chain. With innovative products lead-in times tend to be greater than with more
established products and also restricting the provision of goods and services to a sole
supplier adds risk though sometimes is unavoidable.
There were some challenges relating to interface between the factory and site though
these were reduced or removed through effective communication as the project
progressed.
Given the nature of the project there were some delays in the factory. Any flexibility that
may be allowed for relies upon regular and effective communication between factory and
site.
One of challenges most difficult to overcome was the supply of utilities on site,
predominantly as the utilities companies were found to have protracted design and
mobilisation times. It should be noted that such issues are not unique to this project and
typically can be alleviated by engagement at the earliest opportunity
Variation makes mass production in the factory more challenging. The number of
variations in the modules themselves, largely dictated and driven by the requirements of
the local authority, didn’t always lend itself well to the volumetric construction method.
