Theme: education buildings
After decades of neglect and under-funding, education is again high on the political agenda.
Here we look at a typical Private Finance Initiative schools project and the factors that need to be considered when selecting and specifying materials for this demanding sector Tony Blair's promise of 'education, education, education' is turning into reality, and vast sections of the construction industry are relying on education-related projects to form the mainstay of their workload. My practice, Aedas AHR, is no exception to this.
It is using the expertise developed from decades of working in the education sector to form a key part of the supply chain driven by the latest political imperatives. Work in the education sector typically forms about 45 per cent of the annual turnover of the practice, which has been particularly successful with the Private Finance Initiative.
As a nation, we are seeing levels of expenditure on our schools unheard of since the previous building programme of the 1960s and '70s. The reasons for this recent injection of investment bear a striking resemblance to the previous building boom: the need to address the results of inadequate funding in investments and repair of existing building stock over many years; and a desire to improve levels of educational attainment.
This article deals with the selection of materials for a typical school project, and uses the PFI procurement route as a vehicle.
Indeed, this process should be seen as universal irrespective of the procurement route, though there are specific aspects of the PFI that should create an environment where material selection is given the full measure of importance it warrants.
Tough environment All briefing documents from local authorities highlight the requirement for 'robust and durable materials'. People not associated with the education sector may think that not much damage can be inflicted by relatively small people who (in theory at least) have their minds focused on educational attainment.
They are in for a surprise. Early in my career I was involved with the procurement of premises for the army: operational, training, social and custodial. The need for durability in these situations (where the standard method of opening a door in a barrack room was with the boot rather than with the hand) was taken for granted. Schools are no less demanding environments, and in many instances create greater problems. Military discipline is a moderating influence on the type of damage that may be inflicted in that environment.
Regrettably, the same conditions do not apply in educational establishments, where the taking of 'trophies' as some form of initiation rite is not uncommon. These trophies typically include doors, fixed furniture and sanitary appliances! In these extreme cases, the selection of proprietary products that are capable of demonstrating extreme resistance to removal is likely to find favour.
There is, however, benefit to be gained by sensible space planning at the outset. The risk of physical damage to the building fabric in schools is concentrated in two types of spaces: circulation areas and WCs. The simple act of placing a departmental head's office near to corridor corners, staircases and pupil WCs has a remarkable deterrent effect.
The nature of the timetable and the way the curriculum is delivered within schools create another significant issue in relation to robustness of materials. Every 50 or 60 minutes, up to 2,000 pupils may be disgorged into circulation space, every one of them desperate only to get to the next lesson, armed with coats and bags of a volume similar to the army personnel I used to rub shoulders with. The result is extreme wear and tear to the building fabric. I sometimes wonder whether it would be better to require pupils to stay in the same room for a range of different lessons, with members of staff travelling from room to room. There are signs of this being implemented to some degree. The latest thinking from the DfES is that the same room could be used for teaching English, foreign languages, mathematics and humanities, particularly if information technology can be harnessed to change the physical nature of the teaching environment when the requirements of the subject change. But there is still an issue of long-term maintenance, and the PFI process (at least in theory) is the ideal vehicle for considering this. I say in theory, because there is all too often a fatal flaw in the procurement process, and that is the mismatch between expectation and affordability.
Raised expectations Through the process of Outline Business Case and PFI credit allocation, the project sponsors arrive at a financial model that produces a public-sector comparator (PSC). This illustrates the financial outlay a local authority would expect to incur were it to procure a school through traditional means. It effectively sets the affordability of the project.
The expectation of the end user is rather different. Having being starved of adequate investment over the years, governing bodies and staff naturally expect the PFI process to deliver an enlarged school estate of high quality. They expect that there will be a greater proportion of useable space provided within schools procured by the PFI. Because the affordability limit, typically, is set prior to a detailed consultation with end users, the expectation in terms of physical space is likely to be greater than that envisaged within the PSC. Given the choice, as is so often the case, between amount of space and quality of materials, space wins every time, in the belief that the quality of material in these spaces can be addressed at some time in the future.
There is little long-term feedback on the earliest PFI projects at present, but it will be interesting to investigate this issue further with the benefit of hindsight.
Certain things will be considered good practice in the selection of finishing materials. We prefer to select materials that do not rely on a thinly applied surface colour that, through a process of wear and tear, becomes thin, degraded or non-existent within a short time. This implies through-coloured products such as linoleum or rubber sheet that, even though they may be subject to physical damage by gouging, have a lifespan to first replacement that is significantly greater than for other materials. On occasions we have successfully advocated the use of linoleumfaced internal doors on the basis that, once installed, the maintenance regime typically consists of surface cleaning only. Surface indentations and scratches could be tolerated for some time, as there is no differentiation in colour as a result of physical damage. We know of instances where the same doors have been in place in a hospital operating theatre since 1966 and are still in service today, albeit displaying the scars of innumerable trolleys and beds having been wheeled through them.
The only difficulty the estates manager has with these doors is that hinges and floor springs have had to be replaced several times.
The doors themselves are still going strong.
Corridor walls Walls in classrooms are under little threat of physical damage and are typically occupied by fitted furniture or displays of pupils' work.
In the corridors, however, substantial damage by constant rubbing is the potential threat.
Widening the corridors sufficiently to eliminate this rubbing is the obvious approach, although it is frequently not possible, particularly in terms of affordability. One solution would be to employ high-quality architectural masonry blockwork in these locations, leaving the blocks unpainted although with a judiciously located scuff rail. In other situations, the use of an acrylic paint system produces the necessary lightness and brightness.
The school will typically be programmed, through its facilities-management operator, for periodic redecoration and there is nothing simpler than the re-application of a paint system. Although this is the converse of the previously argued 'through colour' approach for floor finishes, it removes the risk of having expensively applied panelling system that is also expensive to maintain repeatedly.
Industrialise the process Another theme running through the PFI schools process is the need for speed of construction. This has echoes with the previous boom in education construction, that was similarly politically driven. The solution then was all too often the provision of modular or system-built solutions. While this was (and still is) a reasonable solution to the specific problem, there are clearly issues of perception. Some types of modular or volumetric systems do not provide the long-term flexibility required by local authorities.
There are also issues of long-term durability, though the problems associated with the systems are also partly to do with lack of adequate repair and maintenance funding.
There are other ways in which industrialised building processes may be harnessed to deliver the enormous volume of building required. A number of systems can provide in modular form what would be the inner leaf of a traditionally built cavity wall. Using these techniques, the building shell can be completed in about 25-30 per cent of the time required by conventional means. This allows following trades to start earlier than usual, while the external weathering finish is being applied to the outside of the building.
This weathering surface may take many forms: traditional masonry, curtain walling, rainscreen cladding, render, timber cladding etc. Similarly, internal partitions between classrooms may be constructed using drywall techniques, either metal or timber framing with a durable facing board and acoustic lining filling the voids. These walls are typically at low risk from physical damage, unlike corridor walls.
Having provided an internal leaf and infill to what is typically a steel frame with floors of pre-cast or in situ concrete, the roof needs to go on quickly to gain the full benefit of watertight enclosure. There are many systems that offer enhanced speed of installation. These fall into two basic types, both of which employ large-scale sheet-metal components.
One type uses the metal component as a structural liner at the bottom of the roof system. This liner typically supports the insulation and then a more or less traditional application of battens with slating or tiling. The other type employs a metal component as the outer finish, often in the form of a standingseam roof. These systems can be of two distinct types: composite, where a single component offers all the functions of structural support, thermal insulation and external weathering, and built-up systems that require separate components for each of these purposes. The latter approach has the benefit of offering greater flexibility in internal lining sheets and thermal insulation, with the added benefit that drumming from rain may be reduced significantly.
Sustainability on show What better way is there to educate the population on the issues centring on sustainability than through educational establishments?
Much of the waste and inefficient use of natural resources derives from ignorance. Local Agenda 21 requires that, while construction issues may form part of the response, by far the greater emphasis is on raising awareness.
The following criteria may be applied to the process of selecting materials:
lUsing products and materials that minimise wastage.
lUsing products that may be recycled or re-used in the future.
lUsing products that are themselves products of recycling.
lContain the least amount of embodied energy reasonably possible within their manufacturing process.
lIf natural, are from clearly certified and managed renewable sources.
lDo not contain components that will contribute to toxic landfill in disposal, or that need toxic processes to dispose of them safely.
lThe use of products that might create toxic gases in the event of fire.
In addition to the obvious benefits from improved thermal performance that result in low energy requirements, there are a number of options that can form part of the overall building management system. One is the use of greywater. The principle involves the collection of either rainwater or water from hand washing that is stored and re-used for purposes such as WC flushing. At present, however, the cost of the infrastructure often far outweighs the savings in consumption of clean water. But there are enormous benefits to be gained from using this type of system as a teaching aid. A number of systems now offer monitoring packages that measure the volumes of water 'saved' over the course of a year. This raises the issue of the responsible use of natural resources that are otherwise taken for granted. Systems are also available that use geothermal energy to assist with water heating.
Inclusive design In some instances, the choice of material is driven by other functional requirements.
One example is the gathering momentum behind issues of 'inclusion'. The Disability Discrimination Act, Building Regulations, BS8300 and guidance from SENDA (the Special Educational Needs and Disability Act) are dovetailed with the purpose of removing barriers or obstacles that might prevent anybody with any form of impairment using any building. This includes school premises. While much of the impact relates to physical planning and access for people with mobility problems, a host of other, more subtle, issues also have an impact on building design and material selection.
These relate specifically to people with hearing- or sight-impairment. The auditory performance of individual spaces is important. While induction loops or infrared-based hearing-enhancement systems may be appropriate for people with significant hearing impairment, the suitability of teaching spaces for those with only slight impairment is another issue. One piece of research suggests that even pupils with good hearing can only hear clearly seven out of 10 words spoken in the classroom. Imagine the difficulty experienced by anybody with even slightly imperfect hearing. Reverberation time within the room is therefore critical. Given the need, as discussed earlier, for robust and durable surfaces, there is often limited scope in the typical class to provide the necessary 'acoustic damping' to generate the required reverberation times, except in the ceiling space. Some people believe that suspended ceilings are not needed in classrooms. If that is the case, other ways of providing the necessary absorbent surfaces must be found. There are a number of excellent publications from manufacturers that explain recent and forthcoming changes in legislative requirements in terms of acoustic performance. You should consult these as early as possible.
Visual impairment will also affect selection of materials. The expectation is that partially sighted people should be able to use any building facility with the same ease as a normal sighted person. This makes it necessary to use surface finishes to differentiate changes in surface or direction. Materials selected should be available in a range of tonal qualities or colours that enable staircases or ramps to be defined in a contrasting tone.
The government has laid down a challenge and the construction industry is rising to it. The enormous expectation placed upon the industry provides a tremendous opportunity to create something worthwhile and of lasting value. When specifying materials we must not lose sight of the principles of the PFI selection process: understand the requirements, identify the possibilities, and select the most appropriate solution.
David Longfield is a director of Aedas AHR READER ENQUIRIES Altro 1500 Bekaert 1501 British Thornton 1502 Ecophon 1503 Eternit 1504 Fermacell 1505 Forbo Nairn 1506 Hewetson 1507 Ibstock 1508 Kingfisher 1509 Kingspan Insulation 1610 Laybond 1611 Passivent1612 Plannja 1613 Rockwool 1614 Rubberfuse 1615 Sandtoft 1616 SAPA Building Systems 1617 Velfac 1618 Wavin 1619 Enquire at www. ajplus. co. uk/ajdirect