A lesson in affordability and continuous insulation
High-value school refurbishments don’t necessarily require a massive budget. Something as simple as quality insulation can make a world of difference to classroom conditions, as the students and staff at a primary school in Victoria have just discovered.
The perceived high cost of refurbishing school infrastructure has always been an issue for school communities, which is understandable given tight capital budgets and a fear of long-term financial liabilities.
But not all capital improvements need to cost a fortune; in fact, by prioritising works that will deliver the best ‘bang for your buck’, it is possible to make dramatic improvements to the comfort and energy efficiency of school buildings without breaking the bank.
Recently, significant refurbishments were completed at Ringwood Heights Primary School, in Melbourne’s outer eastern suburbs, with a comparatively modest budget of approximately $1 million. The works involved the restoration of the entire southern half of the school’s infrastructure (including multiple classrooms, as well as office and administrative areas), which greatly enhanced the comfort levels of staff and students and reinvigorated the entire school campus.
Project coordinator Roger Vieth, an architect from Crosier Scott Architects, says his firm became familiar with the school while working on a new hall several years ago (part of the Building the Education Revolution (BER) program), and it was clear that some more widespread improvements would be appropriate to bring the main buildings, which date from the 1960s, up to a modern level of amenity. Consequently, he says he jumped at the opportunity to contribute to the latest refurbishment works, notwithstanding the need to strategise expenditure carefully.
“The fixed budget allocation for the project was not enough to do the whole school,” Roger explains, “so we decided to do part of the school – a heavy refurbishment to one wing.”
This wing effectively comprises all facilities south of the school’s main east-west axis, as demarcated by an internal/external corridor.
Roger says early conversations with teachers revealed that high classroom temperatures in summer – exacerbated by corrugated metal roofing – were a major concern, so an effective insulation solution was a clear priority.
“Insulation-wise we didn’t know what was up in the ceiling or in the walls – we had some idea that it would be very limited when we spoke to the staff in depth. They said temperatures typically became uncomfortable at about lunchtime, so we assumed there was very little [insulation] in the walls and very little in the ceiling.”
When the ceilings in the areas undergoing refurbishment were removed, Roger says mineral fibre batts were discovered, “so it actually had insulation that we weren’t aware of.” These batts, he explains, had compacted to a thickness of 25mm or so and were evidently ineffective. In addition, they had not been well installed and had probably been moved around by contractors working in the roof, leading to unwanted heat transference through ‘gaps’ in the insulation coverage. Even if the batts had functioned correctly, they would have done nothing to prevent ‘thermal bridging’, also known as ‘cold bridging’, whereby heat energy is lost through un-insulated framing members, including door and window frames, as well as timber framework.
“So we contacted Chris Davis from Kingspan,” Roger says, “and he said they had a new product, Kingspan Kooltherm® K18 Insulated Plasterboard, which would be perfect for our application.”
Kingspan Kooltherm® K18 Insulated Plasterboard is a rigid thermoset insulation comprising a front-facing, gypsum-based plasterboard sheet bonded to a reverse-side insulation panel. Various thicknesses are available, but the ideal configuration selected for the school was 10mm plasterboard with 50mm Kooltherm® insulated backing material, which provided a product R-value of R2.6.
The insulation material contains a low-emissivity foil to minimise heat gain in summer or heat loss in winter. Other advantages include:
- Stable, even, long-term performance due to the fixed rigidity of the panels (no material compression or displacement to worry about)
- Premium effectiveness and efficiency due to the ability of Kooltherm® insulation products to provide ‘continuous’ insulation coverage, i.e. without heat loss via un-insulated framework materials
- Retention of internal wall cavity spaces for unimpeded rollout of cables and wiring
- Outstanding fire-retardant characteristics.
Thermal Imaging and Continuous Insulation
In mid-July 2013, an independent thermographic survey was conducted at the school to compare the insulation performance of the refurbished southern half with the older northern half. Both wings had classroom heaters, which were turned on and set to maintain indoor temperatures, which were as close to each other as possible. The results were startling, although expected.
The visible framing in the older ceilings (see Figures 8 and 9) indicate un-insulated elements, which are all ‘thermal bridges’, or conductive paths for energy loss. Framing such as this can account for around 15% of the surface area of the ceiling, meaning 15% of the ceiling is un-insulated. As a result, the heating system on that side will be working significantly harder, costing a lot more to operate and affecting indoor levels of comfort.
In the refurbished southern wing, Kingspan Kooltherm® K18 Insulated Plasterboard was fixed directly to the underside of the existing roof framing. No un-insulated gaps ensured a continuous insulation barrier, clearly evident from the thermal images (see Figures 10 and 11). The rooms in this wing were around 2-3°C warmer on average than the northern wing, and every degree counts when it comes to the operational costs of heating and cooling systems.
Of particular interest were the hallways, given that they are without any artificial heating. In the midst of a Melbourne winter, the refurbished southern wing hallways were around 17% warmer than the northern wing, indicating significant heat loss through the framing in the classrooms in the northern wing (see Figures 12 and 13). It also indicates that the continuous KingspanKooltherm® K18 Insulated Plasterboard in the southern wing is working effectively to prevent heat loss, and contributing to retaining heat in the hallways.
Common Sense Initiatives
The effectiveness of the insulation was reinforced by a series of complementary low-cost measures, including clerestory operable windows for cross-ventilation. These powered windows are a great improvement on past manual systems, which required the use of a tall pole to reach and open windows.
“Also, we increased the sun shading to the north by creating a covered deck, which shades some of the windows to stop heat getting through,” Roger says. Additional improvements such as carpets, external access to classrooms, new soft lighting, as well as simple but no less welcome initiatives like bag holders have all contributed to the overall result.
The value of the refurbishments, according to School Principal Mandy Dunn, is obvious to all staff and children.
“The students are able to concentrate and feel more comfortable in their learning environment,” Mandy says. “Our teaching staff have also commented on the reduced noise level and stable temperature in the new classrooms.”
Teachers Cassie Dixon, Stephanie Gibney and Hayley Davidson have also expressed delight in their improved surroundings.
The differences between their old and new working environments, they say, include:
- Better and lower noise levels, especially in the corridors and between adjoining rooms
- Temperature of rooms is always even
- More welcoming for the school community and visitors to the school
- Better line of vision between classrooms – for supervision during wet days inside, and collaboration between teachers and students.
And what about the students’ reactions to the refurbishments? Has their learning capacity improved at all? “Absolutely! There is a sense of pride for the students,” say Cassie, Stephanie and Hayley.
A useful piece of advice to other schools considering a refurbishment, they say, relates to the use of “busy” internal colours and fittings, which might pose difficulties for autistic children.
“Consideration [should] be taken to keep rooms as clutter-free and ‘neutral’ as possible for these children,” they recommend.
Setting an Example
In terms of qualitative improvements to the school, there can be little doubt that the campus achieved significant outcomes for its investment.
By choosing to prioritise works according to the most urgent needs of the school (in this case, excessive heat in the classrooms) and relying on good design to complement new equipment, the entire school community has benefited from a tailor-made, cost-effective rejuvenation. The stage is now set for the refurbishment of the northern side of the campus to complete the project.
There are hundreds of schools of a similar age and construction to Ringwood Heights Primary School just waiting to be rejuvenated – they would be well served to heed the positive example set by Ringwood Heights.