Fresh air, solar windows and impressive toilets - Is this the future of green building?

Like most people, I am extremely susceptible to the power of suggestion. Consequently, I am truly rubbish at poker, endlessly fascinated by hypnosis and will usually try to steer well clear of drug dealers and cult leaders.

So upon strolling round the new Scottish headquarters of building services firm NG Bailey and hearing about its natural ventilation system, I could not be sure if the air seemed so much clearer because I was being told that was the case or if this office was in fact the workplace equivalent of some Highland fell, all fresh air and open spaces.

The thing is though, it really did seem fresher – at least when compared to the rather stuffy workplaces I have become used to, where both the temperature and staleness of the air is entirely determined by the distance you are forced to sit from the air conditioning unit.

In contrast, NG Bailey's new Solais House is decked out with temperature, light and carbon dioxide sensors that feed into a central building management system, which calculates when the air is getting too hot and stuffy and automatically opens the appropriate windows or draws the correct blinds.

The opened windows themselves are positioned high up against the ceiling to exploit the fact that an air stream will stick to a surface. Consequently, when the windows open the air flows along the ceiling to the middle of the room where it drops down to ground level, precisely where the bulk of the desks in the open-plan office are situated.

Obviously, natural air ventilation has its limits when the natural air itself has been the subject of a summer heatwave (an unlikely occurrence in Scotland admittedly, but not unknown). So dotted throughout the building in receptacles in the ceiling are so-called phase change materials, paraffin-based substances designed to melt at 26 degrees centigrade, soaking up five times as much heat as concrete as they do so.

Solais House's near zero-carbon ventilation system is just one of the features that has allowed the otherwise anonymous-looking building in Strathclyde's business park to become the first standard office building in the UK to attain the government's A-rated energy performance certificate. And according to NG Bailey's chief executive Mark Andrews, the certificate and accompanying 42 per cent reduction in energy bills compared with a conventional building of the same size have been achieved with established and relatively mature technologies.

"Solais House is a showcase of what can be done with existing technology in a typical developer spec building," he said at the opening of the office last week, adding that almost all the features included in the 150-seat block could be scaled up to larger developments and would deliver a return on their initial investment within an average of five years.

Of course, keeping the building cool on a warm afternoon at the start of autumn such as the day on which I visited is less of a challenge in Scotland than keeping it warm in the winter, but again NG Bailey is confident that a number of further low or zero-carbon innovations will ensure that, unlike at least one office I have worked in, there will be no need for scarves and mittens to be worn at peoples' desks during the winter months.

For example, the building faces directly due south and the office has a glass front (double glazed, of course) and several large roof lights, both of which ensure that not only is 80 per cent of the building lit almost entirely by sunlight, but on clear days it captures as much of the sun's energy as possible.

Meanwhile, a bore hole sunk beneath the semi-permeable car park surface to a depth of 120m draws up the water required to feed a ground source heat pump. Tucked away in an adjacent outhouse, the heat pump takes the ground water, which is already naturally heated to between 11 and 13 degrees centigrade, and compresses it to a level where it is warm enough to heat the building. According to NG Bailey, the heat pump delivers three kilowatts of energy for every one kilowatt it takes to run it, making it far and away one of the most efficient means of space heating available.

Another form of renewable energy is on the building's windows and rooftop where photovoltaic (PV) glass and a solar water heating array are to be found. Solar panels may seem a strange choice in a country that is rightly renowned for its inclement weather, but NG Bailey claims that even during this miserable summer it has managed to generate 350KW/h in the six and half weeks since the solar PV windows became operational, while the solar water heater is providing up to 60 per cent of the hot water the building requires.

This hot water serves the bathrooms and showers that are arguably the most impressive feature of the building. I am not often impressed by toilets, but those at Solais House really are worthy of mention. Provided by a Swedish company, they have a square-shaped bowl that means they use just two litres (of rainwater collected from the roof) per flush compared with the standard six litres per flush. Meanwhile, waterless urinals are expected to save more than 800,000 litres of water a year and highly polished "sun tubes" work like a child's kaleidoscope, bouncing daylight down into these internal rooms. Like I say, it's a pretty impressive toilet.

Unsurprisingly, all these green features come at a price. NG Bailey reckons the building cost £850,000 more than a comparable office of the same size – a sginficant premium for a development with a total price tag of £5.5m.

It is a premium that many firms will be reluctant to pay, according to CBI director general Richard Lambert, who observed at the opening of the building that the payback period would have to fall from the five years NG Bailey is expecting if these various technologies are to be adopted more widely. However, he added that this was likely to happen as energy bills continued to climb and energy-saving technologies mature further.

There are also questions to be asked about the net carbon savings given that separate offices in Glasgow and Edinburgh have been moved to the new site, meaning some staff will have a longer commute.

However, NG Bailey is confident that a new car-pooling scheme and commuter bus service will help tackle transport-related emissions and the company is adamant that the financial case for such buildings stacks up, particularly when you consider the numerous "soft" benefits that can be realised in terms of staff retention and productivity.

"Companies need to look beyond the traditional ROI [return on investment] when looking at these types of developments," Andrews argues. "If people want to come to a building because it is a nice place to work, that makes a big difference. It is difficult to put that sort of thing on a balance sheet, but it does have value."

Andrews has a point, and as he observes increases in productivity and retention rates of just a few percentage points would deliver significant financial and commercial benefits over and above the £3.3m in reduced energy bills the company expects to save over the 60-year life of the building. And that is even before you consider the potential savings that would be realised in the event of a carbon tax by a building that emits just 13kg of CO2 pr metre squared compared with 41kg for a conventional office.

NG Bailey will have to wait and see if the fresh air, big windows and pride at working in a green building does indeed lead to greater staff motivation once the initial gloss has worn off, or if it was all down to the power of suggestion in the first place. But as I return to my stuffy central London bunker my money is firmly on the former.