Pushing the envelope

Siniat’s Chris Norris tells Building For Education why steel frame systems and gypsum sheathing are proving popular in the education sector

What are the biggest challenges that education projects face?

Naturally, schools and universities want to be ready to accept students in line with term timetables. This means completing builds for September, April and January, right after the holiday periods – leaving little wriggle room for delays in the build programme. It’s understandable therefore that project managers are keen to condense the programme to allow for simultaneous activity, without increasing the risk of delays.

Sustainability is a major concern, too. Recent changes to Part L are pushing project teams to find greater efficiencies – specifically a nine per cent reduction in carbon emissions for non-domestic buildings and a six per cent reduction for domestic buildings – including student accommodation. 

Where can time be saved?

Steel frame systems, as opposed to more traditional methods such as concrete or brick, have become the structure of choice in the effort to speed up construction. SFS is also proving popular due to the trend in using external façade systems – structural elements that provide lateral and vertical load resistance as well as weather, thermal, acoustic and fire resistant properties.

The systems that are often used are lightweight and quick-to-install gypsum sheathing boards that sit on the external face of the SFS frame to provide a weather-tight and air-tight seal, prior to external façade installation. This is an ideal area to save time. Not only is gypsum sheathing quick to install it also reduces silica dust emissions, as it is hand cut.

A real-life example of this is a project my colleagues were involved in with BAM at Bradford College. In the construction of a new six-storey learning facility, we had to tackle some exacting design challenges in order to save time in the build programme. Gypsum sheathing board is normally installed to the outside of the SFS frame, but at Bradford the boards were fitted to the inside, as cradle access systems – allowing access to the outside of the building – were not available until six weeks into the project. Working this way protected the inside of the building from the elements, meaning the internal trades could start sooner. 

How can carbon reductions be achieved?

In practice, there are major opportunities to drive efficiencies by targeting the building envelope. We’re finding that project teams are considering all of the design and material choices in reaching efficiency targets and trying to work in partnership across the supply chain to maximise the benefits.

At the University of Bath, a multi-award-winning campus university, gypsum sheathing was used to provide an airtight seal and improve the thermal performance of a new 350-seat refectory including a cafe, bar, and delicatessen. This formed a central part of a wider 708-room student accommodation project, for which the university has committed to an ambitious programme with The Carbon Trust. The goal: to reduce CO2 emissions by 19 per cent by 2014.

Using gypsum sheathing boards in the building envelope of the refectory was a certain way to improve efficiency. Fitted without expansion gaps, the boards are dimensionally stable, unlike cement particle boards, meaning that heat loss and energy wastage is reduced. 

Can these processes also affect positive learning outcomes?

Evidence-based design research has shown that students’ ability to learn is dramatically affected by their physical environment. Noise, temperature, air quality and aesthetics all have an influence. Achieving a building envelope that can help to alleviate these discomforts is vital to positive learning outcomes.

Getting an airtight seal will prevent outside airborne noise leaking in and maintain air quality, as well as keeping rooms cool in the summer and warm in the winter. As for the aesthetics, the building envelope is the basis for design, so getting the technical requirements right makes eye-catching designs possible. 

Chris Norris is architectural specification manager at Siniat W: www.siniat.co.uk