3 Tips for Planning Vegetative
PREPARATION IS KEY TO AVOIDING MAJOR MAINTENANCE COSTS
Vegetative roofs are a great way to combine sustainability with amenities, as they can be inviting
places for building occupants. However,
improper planning for their maintenance
demands means you might be dealing
with more than you bargained for in
terms of costs and labor.
Prepare for the responsibilities of a
green roof with these three tips.
1) Enlist Multiple
One of the biggest mistakes facility
managers make with vegetative roofs
is consulting with only one expert. A
roofing expert will help you identify the
structural demands of a vegetative roof,
but they can’t attest to regional and
climate-based concerns about plant life
and the maintenance required.
Therefore, you’ll need two types of
experts – one for roofing and another
for vegetation and maintenance who is
knowledgeable about the best kinds of
plants for your climate. This person will
identify plants that require less upkeep
and that thrive in your environment.
Of course, depending on what kind of
vegetative roof you’re looking into, you
will need to include plant life that’s compatible with the structure of the roof.
Make sure your roofing and vegetation
consultants have an open dialogue to
ensure that the roof can work optimally
for as long as possible.
2) Know Your Roof
If your roof requires a lot of maintenance work after a severe weather event
or from wear and tear over time, knowing the details of your roof’s installation
and materials will help you save big.
Familiarize yourself with your roof’s
warranties. Compare your detailed
record of the roof’s installation with your
warranty policies during major repairs.
“In general, warranties insure the
owner against defective products and/or
inadequate installation by the contrac-
tor,” notes the Whole Building Design
Guide (WBDG). “They can cover all prod-
ucts of the vegetative roof installation
including the waterproof membrane, root
barriers, filter fabrics, growth medium,
drainage layers, etc. as well as the work-
manship of the installation subcontrac-
tors. There are several waterproofing
manufacturers that will warrant the
entire vegetative roof system, including
removal and restoration of the overbur-
den, if they provide all of the materials in
the original construction.”
To stay ahead of major maintenance
needs, WBDG identifies four vegetative
■ How durable are the components of
your roof? Identify when they will
need replacement or checkups.
■ Did one contractor install all the
features of the vegetative roofing
system (e.g. waterproofing
membrane, growth medium, etc.), and
are they from one manufacturer? If
you obtain all components from one
manufacturer, all of the parts of the
green roof will be covered under one
warranty and there won’t be liability
disputes if there is an issue.
■ If a number of manufacturers and/
or contractors are involved, clearly
define the extent of each warranty
and what they individually cover. For
example, does the membrane
warranty also include reasonable
uncovering and restoring the
vegetative assembly in order to
perform the warranty work?
■ Does the warranty cover the plants?
Many vegetative roof warranties don’t
cover plant survival, but some include
it as long as the owner purchases a
3) Establish a
Transitional Period for
Unlike other building systems and
roof types, a vegetative roof is a living,
breathing ecosystem. This means many
things can go wrong and cause issues
for your building.
To counter this, WBDG suggests
including a minimum two-year maintenance and warranty period in any initial
construction contract. This ensures plant
establishment, maintenance personnel
training and comprehensive assessments
of local pest issues.
If you can implement this two-year
period for your vegetative roof, you will
be able to avoid a number of serious
issues that require expensive solutions.
After that period has expired, vegetative roofs should receive maintenance
from trained personnel at least twice a
year, notes WBDG. If untrained people
perform maintenance, manufacturers are
likely to void any warranties.
Justin Feit Justin.firstname.lastname@example.org is
Associate Editor at BUILDINGS.
TRAINED PERSONNEL SHOULD PERFORM MAINTENANCE CHECKS FOR
GREEN ROOFS. They know what to
look for and can keep your warranty