'Slender' roofs won't bear a solar future'
"If you've got a slender roof, it's really built to the minimum specification. It's structurally adequate but when it comes to additional roof capacity, there is none.
"Retro-fitting of roofs is financially unviable. Structural engineers work at the whim of the owners."
It can cost an extra $19 per square metre to strengthen a roof to the required capacity, on Mr Hoogesteger estimates.