Project Summary

The design for Ysgol Bro Hyddgen seeks to create an inspirational environment and a sense of progression for pupils in the rural Powys town of Machynlleth, which provides ‘cradle to college’ mainstream education from nursery to sixth form. Balancing the changing needs of pupils and staff as they progress through a possible 17 years at the Welsh language school was a key design consideration, as well as the sustainable future for the school, which is underpinned by a sustainable Passivhaus design.

Design Rationale

The angular forms and intersecting arrangement of massing is softened by an interesting and varied palette of Welsh, natural materials. As a gateway site to the town of Machynllyth, the design strikes an important balance between the surrounding hilly woodland countryside and the introduction to the towns’ development.

Due to complete in September 2020, the new 6500m2 school will be built on Ysgol Bro Hyddgen’s current playing fields, with the old school being demolished after occupation to make space for car parking and sporting facilities, including a 3G pitch to provide pupils and the community an accessible ground for team fitness during the wet winter months.

Community Consultation

Throughout the design process a comprehensive consultation programme has been in place, with the results contributing to design development. Involving various stakeholders at early stages of the design process has allowed the design team to respond to comments and suggestions in the application proposals. The programme of consultation events is ongoing, but to date has included consultation with local school children, the headteachers, staff and catering and maintenance people and a general public consultation for the community. A scale model was created for the purpose, along with large presentation boards and virtual reality animation to help the stakeholders understand and visualise the scheme.

Thermal Bridging Assessment

Using a combination of BIM, Passivhaus Planning Package and Psi-therm, we identified where thermal bridges were occurring on the school and investigated specifically at what areas the highest risks occurred. Once the thermal bridges had been ranked, we were able to undertake bespoke detailed design work to detail out the high-risk areas, simplifying the building processes with as little disruption to the insulation and airtight layer as possible. Sometimes this would involve finding alternative solutions or a fresh thinking about product specification to improve the risk-ratio. For example; on this school project, where budget is an important consideration, we re-thought the shading strategy, moving from a fixed brise-soleil solution to a free-standing canopy to reduce the use of expensive thermal breaks required. Exercises like this help the design team to understand where the costly thermal breaks are so that the building can be more practically quantified at early stages.

Managing BIM

Architype were BIM manager for this large-scale project. Bringing together and coordinating the project information models from the M&E, structures, landscape and architectural designers. By running a full clash detection process we de-risked any potential issues and optimised buildability and synchronisation, resulting in streamlining the design stages. At this early stage, issues were picked up on and rectified, improving project efficiency and minimising the cost and time implications to the project.

One example of this was realising that the plant room was not large enough. To extend the plant room by the necessary amount would have had implications to the layout and area options. We were able to show the client, using 3D views, how moving the plant room up to the roof area was an appropriate solution that did not impact visually on the design. We also used VR (virtual reality) with the clients to demonstrate how hub spaces would work, easing the clients reservations and letting the design progress quickly. .

BIM to PHPP coordination

With Architype having undertaken so many Passivhaus projects, we felt there was a more efficient way to inform the data for the Passivhaus Planning Package, by utilising the data in the building information model. Ysgol Bro Hyddgen was the first project that we trialled this method on. We worked closely with Passivhaus certifiers to ensure that our methodology worked and would remain acceptable to the Passivhaus Institute, who would ultimately certify the building.

Taking data from the building information model, we were able to display accurate values of each area in the school, which in turn created a more simple and legible visual, accessible for people not trained in Passivhaus design. It also had the added benefit of a much earlier understanding of how the building was performing in PHPP allowing for glazing design to be adjusted to maximise design and solar gains.

In this trial of coordinating to BIM and PHPP elements, we found most of the information translated well and in some cases we understood that more customised algorithms were needed for the more bespoke areas of the project. Our next steps are to explore how we can implement this on different typologies and gather even more data such a full glazing take off for future projects.