Bullnose & Concave Curves

The best looking verandahs are those where both the Bullnose (or Concave) curve; and the height between the top of the fascia board and the top of the wall plate falls within a specific range.

The radius of the bullnose curved section on traditional Bullnose verandahs in Adelaide is generally between 400 mm – 600 mm, with the length (circumference) of the curved section generally being slightly longer than the radius. e.g. a 500 mm radius curve combined with a 520 mm – 550 mm length of curve is common.

For Bullnose verandahs 1600 mm – 1800 mm wide, a height difference (from the top of the fascia beam to the top of the wall plate) of between 450 mm - 650 mm is most common and a satisfactory appearance can be achieved. Shallower depths can be used but the balance between seeing both the curved and straight section of the bullnose sheet may be jeopadised.

Concave curves generally look best when the difference in height between the fascia and wall plate is deeper (e.g. 600 mm – 800 mm), rather than shallow. The depth of the curve also influences the appearance. If the depth of curve is excessive the roof may leak at the fascia line, but if the depth of curve is too shallow it may appear as if straight sheets have been used and they have sagged.