UK Building Regulations
for Ventilation and 
Energy Conservation
Read VEETECH's
Response - 
Whatever Happened 
to "Keep it Simple - Stupid"?

  Ventilation Energy and Environmental Technology
                                     from VEETECH Ltd.              Updated 11th November  2009

Building Airtightness - Is Tight Right for British Homes?
Mechanical Ventilation Case Studies point to an 
Energy and Indoor Air Quality Disaster for Homes 

Coventry University Library (UK)

Energy Pollution and Health

Energy efficiency has become a cornerstone for achieving sustainability. This is not surprising  since the major  proportion of global pollution is derived from energy conversion. Apart from concerns over climatic change, increasing evidence shows that pollution generated by the burning of fossil fuels has an identifiable impact  on the health of people. In recent times, studies have shown conclusive epidemiological evidence that such pollution results in poor health and premature death, especially in urban environments. Ultimately, as individuals and pressure groups begin to assimilate this evidence and seek legal redress, the health aspect of energy conversion will almost certainly transcend the pressures of global warming as the motivator towards establishing clean energy policies. In any event, gas and oil reserves are predicted to be reaching peak production. Thus it is probable that the fossil fuel age has already  reached its climax and, hence, this form of fuel will rapidly cease to become an economic source of energy.

Renewable Energy

Fortunately ‘renewable’ sources of energy are beginning to show promise.  Proponents have always insisted that energy from the sea, wind and sun can more than meet our energy requirements. Now, technology is beginning to back this claim. In addition, fuel cells are becoming viable as high intensity electrical sources, while the effective hydrolysing of water, to produce the necessary hydrogen, is becoming a reality. As a consequence, the remaining key ingredient, i.e. the need to be able to ‘store’ energy, is coming into place.

Building Energy Use

On the demand side, the heating, cooling and lighting of buildings accounts for approximately 40% of all energy use and, consequently, easily matches  that of the transport sector. Unlike vehicles, however, with, perhaps, a 5 – 10 year life span, the life of a building could exceed  100 years or more. Thus today’s buildings could well be those that are in the forefront of the renewable energy age. Many countries have now developed energy efficiency requirements and guidelines for buildings but much still needs to be done to ensure that buildings both meet these targets and provide occupants with the necessary level of comfort. Without designing for comfort, ad hoc, quick fix solutions such as electrical heaters, portable air conditioners and extra lighting will quickly have an adverse impact on building energy use.

Cooling

An area of particular concern is the ever-growing need for comfort cooling.  Even in the cooler zones of Northern Europe, the demand for cooling is resulting in the growing use of air conditioning units in offices and homes. In part they are being installed to cope with warmer outdoor conditions but, probably, their principle application is to offset the impact of internally generated heat load and solar gain. Whatever the reason, it is an error to assume that the market for mechanical cooling can be controlled or diminished, since the demand for thermal comfort is here to stay. Evidence of such demand is already present in the huge numbers of portable air conditioners finding their way into buildings. Invariably they are of the least efficient design and, more often than not, can be seen blowing cold air over occupants while the exhaust hose is left wrapped around the base of the unit.

If sustainability is to be taken seriously, therefore, it is essential to meet the need for cooling head-on.  With good design of the building envelope, combined with careful control of indoor thermal sources, it is readily possible for a building interior to operate at 3 degrees dry bulb temperature below the peak daytime outdoor value. This represents an enormous cooling potential that can ensure good comfort conditions in a building for much longer periods than is possible in a conventional building.

‘Top-up’  Cooling

Thereafter, however, a pragmatic approach to mechanical ‘top-up’ cooling is necessary. The key is to identify how much cooling is necessary and to determine the most efficient means (both in terms of energy and cost effectiveness) by which this may be  achieved. This should result in a complete rethink about cooling, especially in localities where outdoor temperature and humidity conditions are rarely oppressive. In many climates top up cooling, aimed at the most demanding design requirements, should be achievable using    substantially downsized cooling approaches that match or surpass the cooling performance of conventional methods. Apart from energy considerations, this could result in much  reduced capital cost and a reduction in the need for the space necessary to house the system and associated ducting. 

Several modern buildings are beginning to incorporate passive measures aimed at securing a good thermal comfort. A recent example is the library at Coventry University, UK (see Figure above). This is listed as the largest wholly naturally ventilated building in the world. It combines thermal mass, passive cooling, daylighting and natural ventilation to achieve the desired health and comfort conditions.