Preventive Medicine
Feb 1, 1998 12:00 PM, Dick Jozwiak
Shattered bottles. Rocks. Tree limbs. Balls of all sorts. While these may not sound like much of a threat by themselves, each one or a combination can cause extensive damage to a school's roof. Factor in bad weather and acts of God, and the potential for rooftop damage becomes a never-ending concern.
The most effective weapon against roof damage is regularly scheduled preventive maintenance checks. While with single-ply thermoplastic roofs these checks are minimal, they are valuable.
Facility personnel should set up a program similar to those created for washing and waxing floors. The program should require a qualified individual to walk the entire roof, checking all the edge details to make sure nothing has come loose due to high winds. Other areas to inspect include the penetrations and skylights for deteriorating sealants or any vandalism that may have occurred, all of which may cause leaks.
Establishing a checklist also can make roof inspections convenient and beneficial. Once the inspection has been completed, keep a maintenance file so that past inspections can be reviewed. This file also should include notes about any outside servicing. These records will help facility personnel determine how and why the damage occurred, as well as possibly who caused the damage.
Facility personnel also must regularly check rooftop air-conditioning units to see if there are loose panels, as well as to make sure the condensation liners are operating properly. It is good practice to inspect the roof around the air-conditioning units following any servicing from outside contractors.
Walking lightly To help deter accidental third-party damages, walk pads or protection mats are being specified on most single-ply thermoplastic roofs. Walk pads can aid in eliminating any punctures that may occur around air-conditioning units. These protective pads usually are designed to surround all air-conditioning units and are sometimes placed around the entire roof. Although there may be an additional cost for the walk pads during installation, the long-term results and savings are worth it.
Restricting access to the rooftop also can reduce maintenance. With a ballasted single-ply thermoplastic roof in which a layer of stone covers the roof membrane, facility personnel must be more attentive when inspecting the roof.
Wind scour sometimes can cause problems in the corners of a building that has a ballasted single-ply thermoplastic roof. Depending on the flow of wind on such a roof, the small stones can be displaced, requiring facility personnel to rake the stones back in place. If this continues to be a problem, consider installing paver tiles to alleviate the displacement of stone.
Inspect any areas that possibly could leak. Also, make sure that all air-conditioning units are level on the curb and properly sealed. If they are not, condensation and rain-along with snow-can cause problems and leaks.
Down the drain Other vital parts to a single-ply thermoplastic roof are the drains. Regardless of how many drains are on a roof or where they are located, check every one monthly. Leaves, branches and other debris can clog the drains and cause standing water on the roof. If debris has collected on the rooftop, facility personnel should clean the entire roof thoroughly.
Leaves and stones are the worst enemies to roof drains, so make sure that leaf grates and stone guards (ballasted roofs) are used on all drains. A plugged drain during a thunderstorm can cause damage to a roof structure, so precautions can save money, manpower and time. Furthermore, anytime there is a windstorm, tornado or other inclement weather where debris may accumulate on the roof, check for punctures and other structural damage.
Periodically check the termination of wall flashings, which is a crucial part to a leakproof roof. If a wall flashing is not securely attached to the parapet wall, water can leak in between the two areas and cause damage. Facility personnel should be well-versed in the particular product line that was used for the roof installation. This way, if a minor repair is needed, school staff possibly can do the work-at least on a temporary basis until the appropriate contractor can be contacted.
If a school's single-ply thermoplastic roof experiences damage, regardless of how minor or severe, contact the contractor who installed it. A thorough inspection by the appropriate roofing professional will ensure that the repair is done correctly.
