Regular roof inspections and maintenance are the keys to realizing the full life cycle of a roofing system, and that’s good for an architect’s reputation as well as the environment. By detecting minor defects and repairing them early, it is possible to avert major problems in the long run.
Premature roof failure places a heavy burden on the environment. Considering the energy costs for manufacturing new roof materials and the waste associated with the removal and disposal of spent ones, it could be said that a roof inspection is the single most important activity that an environmentally-conscious building owner or facility manager can do.
One of the most valuable services that a roof consultant offers is a keen eye for roof inspections.
It is an axiom of roof consultants that commercial roofing systems should be inspected twice per year.
First, inspections should be performed as early as possible in the spring to assess any damage that was incurred in the winter and allow ample time to schedule needed repairs over the summer. It is better not to wait too long or else it may be too late to complete the repair work before winter returns.
Second, the roof should be inspected before the arrival of winter to prepare for the upcoming winter by ensuring that the drains are working properly and there is no damage that could be difficult to repair when the roof is covered in snow.
Who Should Inspect
Many facility managers are qualified to perform roof inspections. A basic survey for obvious damage is better than no examination at all. Damage often occurs near flashings, wherever the roof meets a wall, a drain or other penetration.
Usually the damage is apparent, but an untrained eye often will overlook the obvious. A moderately experienced facility manager can check the roof membrane, flashings and drains for obvious problems. If defects are spotted then an independent roof consultant should be called for an objective evaluation of the roof’s condition. In this manner, serious problems can be averted without concern that unnecessary roof work is recommended.
A more complex issue is determining when it is time to replace a roofing system. If you don’t get the full life out of a roof then you are doing damage to the environment. A registered roof consultant will not recommend replacing a roof that hasn’t reached the end of its service life. That’s where experience comes in. A roof consultant can tell when a roof is still in good working condition and when it should be replaced. He will help the building owner eke out a few more years of service life whenever possible, which is especially appreciated in difficult economic times.
The objective of a roof maintenance program is to extend the expected useful life (EUL) of a roof system. The elements comprising a successful program are periodic inspections, routine maintenance and repair, and correct application of quality roofing products.
Many maintenance programs have been developed to monitor the conditions of roofing systems and schedule repairs. Regardless of the age of the roof, regular inspection and maintenance is vital to ensure that a roof reaches or exceeds its expected useful life. As a roof approaches the end of its life cycle, maintenance decisions become especially critical.
What to Look For
Membrane defects vary according to roof type. For a three- or four-ply built-up roofing system, be observant for exposed felts, wind scour, blisters, asphalt migration (down slope), ply slippage (down slope), exposed embedded metal, inadequately filled pitch pockets, splits or tears. Common defects in a two-ply modified bitumen system include open seams, inadequate bleedout, exposed bleedout, blisters, fishmouths, wrinkles, exposed reinforcing scrim, loss of granules, inadequately filled pitch pockets, punctures, tears, or splits. Single-ply roofs can have problems with open-lap seams, short-lap seams, fishmouths, wrinkles, inadequately filled pitch pockets, punctures, tears, or splits. A standing-seam metal roof can have open seams at standing seams, missing or backed-out fasteners, buckling of pans, scratches, dents or corrosion.
Flashings are frequently found to be a problem source. In general, the assessment of flashings is similar to the assessment of the membrane insofar as the type and extent of defects. Two important concerns not associated with membranes are the vertical attachment and the counterflashing. When counterflashings appear damaged or flashings do not appear to be watertight and performing well, then plans should be made to get them repaired.
The slope of the roof and drainage are other important factors. Roof drainage and roof deck slope are two distinctly different parameters. An adequately sloped roof deck can have inadequate drainage, and a flat roof deck can have adequate drainage.
A visibly clogged drain is a very common problem in the spring which can easily be noticed and fixed by the building maintenance staff. Just remove the debris from around the roof drain and also from the roof. An independent roof consultant can also assess the proper functioning of the drainage system by noting the roof slope to the drains and general roof slope; and the size or amount of drains, gutters and scuppers.
Drainage refers to the ability of the system to carry water away from the roof and the building. The building code usually dictates the minimum level of drainage required for a roof. Conventional design calls for at least four drains for larger roofs, a minimum of two drains for roofs under 10,000 square feet, and a maximum spacing of 75 feet in any direction for drains.
Other factors that are important to note in a roof maintenance program are the relative costs of repairs compared to the cost of replacing the roof; the leak history of the building; the durability and toughness of existing membranes; the type of membrane attachment; the susceptibility to roof traffic; and the importance factor, meaning what is the use of the building under the roof area.
A typical roof maintenance program will be scored on various factors, and on a relative scale of 1 to 10 based on the knowledge and experience of the roof consultant. The conditions of roofing sections can then be prioritized and ranked for maintenance or repair.
Partner With a Consultant
A registered roof consultant is not going to recommend roof repairs or roof replacements that are not needed. RCI members typically specialize in the entire building envelope. They have deep knowledge of roofing, waterproofing and exteriors. By their code of ethics, RCI members are objective in their project and product recommendations. RCI members know how to cooperate with manufacturers to obtain accurate technical information about the reliability and performance of building products and their suitability for a particular application. Additionally, many of the association’s members hold the professional designation of Registered Roof Consultant (RRC)®. These consultants have demonstrated skills through written exam, character reference and documented experience.
Most modern roof membranes are rugged enough to withstand the forces associated with winter weather. Aside from actual structural damage to the building from excessive loads, snow and ice on the roof is not usually the cause of damage to the roofing membrane. However, severe winter weather does contribute to the wear and tear on the roof. Water tends to remain longer when there is snow and ice on the roof because the water does not drain. So a small defect that may not leak during a typical rain event could leak when snow and ice is on the roof.
A regular maintenance program and inspection should be in place every year, regardless of the severity of the weather in any particular region. If the building owner is having a problem and does not have an in-house expert, it would be prudent to call a roof consultant, who can provide an objective and independent assessment.