By Lood Welgemoed, Boogertman and Partners
It never ceases to amaze me how architects still don’t apply the basic principles of sustainable design from the very first conceptual sketch of a project. I see this in large commercial buildings and particularly also at domestic scale. What they don’t seem to realise, is that the occupant of the building, whether a business or a family, will suffer the consequences long after the architect has moved on. These might include inflated energy bills due to enhanced cooling and/or heating, or simply poor comfort levels. We all know that people are more productive in a comfortable environment, so why not stick to what our forefathers had known centuries ago, but we seem to have forgotten since the onset of the industrial revolution.
For me the most basic of basics is building and glazing orientation. Our African sun is fierce, and east and west facades really ought to be solid with little or no windows. North is great for heat and natural light, but shading needs to be applied liberally. South can be quite transparent as shading is not really required, however the more glass, the less insulated the building will be unless you specify double glazing, so strike a balance between natural daylight and U-values. Otherwise you might end up with a freezing building in the winter.
Next is mass versus insulation. In many ways we are blessed with mild temperatures throughout the year compared to the extreme weather conditions of Europe or the United States. This is particularly true of the Highveld, where the biggest challenge is the temperature fluctuation over the course of a winter’s day. So, mass is good for storing heat on a summer’s day and slowly releasing it at night, however, this only really works in the summer. Ask most inhabitants of older Pretoria homes and they will tell you how freezing their houses are in mid-winter. Still, it’s only really a three-month problem out of twelve. Insulation really helps, particularly under the floor and on the roof, where approximately 70% of the sun’s energy hits. So in winter insulation can really contribute to the cold spike, but in my opinion and from experience the best designs include elements of both mass and insulation.
The main reason for particularly focussing on these two basics, orientation and mass/ insulation, is that these are no or low-cost interventions which can and should be accommodated from the earliest design inception. If done properly, the benefit will be invaluable and the cost negligible. Any other green incentives will then be a bonus and will contribute to the overall sustainability of the project in compliment to the basics. If not done correctly, then no amount of money thrown at other green programmes or initiatives to improve occupant comfort will ever solve the fact that the building is inherently unsustainable.
Sustainability is not an optional extra to be picked from a shopping list. If this was the case, then most clients would simply not choose to spend the money upfront. What we are finding to the contrary is that, if we design the greenest possible office buildings by getting the basics right, they comfortably achieve a four-star green rating and a five-star rating is so tangibly close that clients are happy to spend the little bit extra to achieve it. This is great for public relations, attracts blue chip tenants and helps them to achieve the best possible rents.
Boogertman + Partners
Tel: 012 429 7300