Above: Left: ‘Letterbox’ solution connects 3 rooflights without impacting too greatly on roof structure. Centre: New beams allow complete removal of flat ceiling. Right: not in a structural capacity, but these beams add sense of scale to a very tall space.
I love light. Daylight and sunlight both have a place in buildings. A soft even north light will provide consistent lighting over the course of the day, whereas an east facing window will be a joy on sunny mornings. A south facing rooflight will track a ‘hotspot’ of light through the room as the sun passes over, bringing a dynamic and changing light level.
I work a lot in existing buildings, and often try to bring as much light into projects as possible, sometimes in unexpected places. I have recently completed a few projects where an existing flat ceiling has been opened up to create height as well as light. Installing rooflights on a pitched roof and boxing in around them down to the ceiling can bring in lots of light and be a useful solution but not always as dramatic as opening up the whole ceiling.
Velux lightwell to flat ceiling
One way of achieving height and a sense of grandeur, is to vault the ceiling, or have the ceiling up high sloping directly beneath the existing roof surface. This is only possible in certain situations as taking away the ceiling has an impact upon the structural mechanics of the building. Roofs are normally triangulated with the bottom chord (the ceiling) performing a tension role. This stops the sloped roof part from sliding out and apart. Essentially it ties the two walls together. Imagine a house of cards (just 3 cards), the tension force holding the cards up is the friction between the two stacked cards and the horizontal bottom one that ties the two together. If you take away or reduce this friction, then the ‘roof’ slopes will slip down and collapse. To stop the walls being pushed apart by the roof, some structural solution is required.
It is usually easiest to provide a number of tension beams or cables across the space. I’ve had a few projects recently that have benefitted from the use of beams in the exposed roof space. They enliven the space, add a sense of scale and help keep soaring ceiling heights in check. (They also stop the building from falling down!)
With some lighting they can look very purposeful, either in contrasting timber or painted a subtle shade.
While not always applicable in each project, I do love vaulted ceilings with big rooflights!