potential disadvantages of green roofs:
Green roofs are very versatile, but they’re not appropriate for every project:
increased structural loading:
-However, some extensive systems, fully saturated, weigh no more than gravel roof ballast would.
expensive and complicated roof maintenance:
-Some new technologies like electric field vector mapping (efvm) systems can reduce this risk, and modular systems can facilitate access to roof membrane.
increased capital cost: -a common rule of thumb
is that green roofs cost twice as much as conventional roofs, but the
membrane will last twice as long. That’s probably hogwash; I think they’re
probably at least three times as expensive.
increased maintenance:
-Most systems must be weeded and watered for one or two years, but some modular systems are installed fully planted.
