Published in Maintenance Solutions
(February 2002)
High-Level Decisions
Successful roofing management relies on a
strategy that features planning, regular inspections and timely
follow-through
By Jeff Evans
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Rare
is the organization in which roofing funds flow like water. Most
maintenance and engineering managers face the quandary of too
many problem roofs for the money available. The problem might
well be a lack of money, but it could it also be the lack of a
coherent roof management plan.
Most managers in commercial and institutional facilities agree,
in theory, that regular inspections are an essential part of a
roof asset management program. They also would recognize and
agree with the basic roof management tenet that regular
inspections and routine maintenance reduce ownership costs,
reduce leak frequency and severity, extend roof life, and reduce
management inefficiencies.
But, in practice, by the time many organizations think about
starting a roof management plan, they need a roof replacement
program. The opportunities to maintain and repair have been
supplanted by the obligation to fund and implement roof
replacements.
If organizations can extend the life of each roof under
management one year, they break even on the roof management plan
costs. If they can extend each roof by two or three years, the
plan can reduce roof expenditures by a multiple of its costs.
So why don’t all organizations have a viable roof inspection
and maintenance plan? Is it inertia or a fear of the unknown?
It’s hard to fathom. What is certain, however, is that some
plans never get started. Also certain is that even a minimal
plan is better than no plan. The best advice for managers is to
get started now.
Getting
started
The
temptation in beginning a roofing program is to jump right in
and start filling pitch pans. This would be a definite
improvement over no roof management effort at all, however, but
the best first step is for managers to take an inventory of
roofs under their care. This inventory begins with developing a
historical file for each roof that includes these pieces of
information about each roof:
- date
of installation
- installing
contractor
- roof
system manufacturer
- existence
and duration of warranties
- type
of roof membrane, insulation and roof deck
- leak
history, including any warranty claims and their resolution
- repair
history, dates, type and cost of repairs.
Roof
assessment
With
all of the roof information in place, the next step is to get up
on the roofs and perform a condition assessment. No roof can be
managed appropriately without first knowing the roof’s history
and then understanding its current condition. Managers can best
obtain current roof condition by scheduling roof inspections or
surveys.
The person performing visual roof surveys should be familiar
with the design, installation, repair and types of failure
specific to the roofing system being surveyed. Whether surveys
are done by in-house staff or contracted to a consultant depends
on the technical competence and availability of resources.
In-house personnel who have had training in roof inspection,
diagnosis and repair can perform limited overview surveys.
A roof survey should include: an examination of roof membrane,
flashings, sheet metal flashings, drains, gutters, etc.; an
evaluation of observed conditions that might impact the roof
system’s long-term performance; documentation of deficiencies
requiring corrective action; and development of long-range
preventive maintenance (PM) needs.
Survey documentation should consist of a written report or
checklist, photographs, and notes on a roof plan indicating
conditions observed. The roof plan should supply enough data to
facilitate performance of the required repairs. Several
checklists are available for documenting conditions observed
during a survey, but these checklists sometimes fall short of
conveying all conditions assessed over the long term.
Survey
frequency
How
often an organization needs to perform various tasks associated
with a roof PM program depends on the roof’s age and
condition, environmental influences, rooftop traffic, occupancy
sensitivity, size and roof accessibility. The following
guidelines can help determine the frequency of the tasks:
- Perform
comprehensive visual roof surveys semi-annually. But for
large roof areas in good condition with limited rooftop
traffic, managers can perform a comprehensive survey each
spring. A limited overview survey in the fall can ensure
integrity prior to winter weather.
- Conduct
warranty surveys before a contractor or manufacturer’s
warranty expires. This allows the repair of any covered
deficiency before the expiration of the contractor or
manufacturer’s possible monetary obligations.
- Perform
monthly housekeeping surveys on most roof areas. Surveys
help identify potential problems. In some cases, managers
might need to increase the frequency of surveys. For
example, during the fall, roofs adjacent to trees might
require that crews remove vegetation weekly.
- Schedule
corrective steps or repairs soon after the survey. Delaying
corrective repairs allows small, isolated deficiencies to
become major problems that can be expensive and difficult to
repair.
- Conduct
roof moisture surveys on a three-year cycle unless specific
conditions exist that warrant more frequent surveys or
moisture is present in the roof system. Perform the first or
baseline survey before a contractor’s warranty expires so
repairs can be covered under the warranty terms. In any
case, the first roof-moisture survey should be performed
within the first two to three years after installation.
Formulate
a plan
The
information gathered during an inspection does no good if it
sits on a shelf accumulating dust. Managers need to study the
information, as it will help identify opportunities to make
repairs, conduct maintenance or anticipate re-roofing.
Formulating a plan will help managers communicate better with
upper management, roofing contractors and maintenance staff.
Perhaps the most important goal of all is to avoid having a roof
replaced before its design life is reached or having to perform
emergency repairs at the least opportune time. To avoid letting
a good roof sit neglected and doomed to early failure, managers
can begin the effort with a well-devised roof inspection and
maintenance plan.
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Different
Roofs, Different Concerns
Many common elements exist between various generic roof types.
Each type has distinct aging characteristics and develops
different defects over time. The defects an inspector finds in
built-up roofing are different from those found in an EPDM
rubber roof. Listed below are several common conditions that
affect a roof’s long-term performance, regardless of roof
type, as well as differences to look for in the three most
common roof systems:
All
low-sloped roofs
- Underfilled
pitch pans
- Clogged
or restricted drainage
- Debris
or sharp objects
- Chemical
exhaust, particularly oil and solvents
- Collapsed,
wet or damaged roof insulation
- Insufficient
fastening of sheet metal copings, gravel stops and
counterflashings
- Poorly
sealed flashing terminations.
Built-up
roofs
- Loss
of felt surfacing, gravel, aluminum coating or asphalt
surfacing
- Felt
erosion or loss of plies
- Membrane
aging, such as alligatoring and brittleness
- Membrane
damage, such as punctures and cuts
- Membrane
defects such as blisters, splits and ridges
- Flashings
aging, splits, open laps, racheting and slippage
- Poorly
sealed flashing terminations.
Modified
bitumen roofs
- Blisters,
especially at laps
- Loss
of surfacing, especially SBS modified bitumen membranes
- Open
laps
- End
lap shrinkage
- Membrane
aging, surface crazing and pitting
- Membrane
damage, such as punctures and cuts
- Flashing
defects, blisters, open laps and slippage.
Single-ply
membrane
- Open
membrane laps
- Membrane
damage, punctures and cuts
- Inadequate
attachment, ballast or membrane displacement, shrinkage
and wind damage
- Membrane
aging, crazing, stiffening and brittleness
- Flashing
defects, open laps and loss of attachment
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