By Tom Irvine, RRC, CDT
As the hurricane season approaches, it seems appropriate to review some basic roof-related preparedness activities. The hurricane season lasts from June 1st to November 30th, with the peak season from mid-August to late October.
High winds, heavy rains, and flooding can each have disastrous affects on roofs. Wind can obviously cause roofs with poor wind uplift resistance to blow off. However, a more common problem is interior leakage due to roof damage from windborne debris. Unfortunately, many inches of rain typically fuel these leak locations prior to the completion of repairs. During flooding conditions, roofs that have drains piped into the storm sewer can be at risk of severe ponding if emergency overflow drainage provisions are lacking.
Development of a detailed hurricane preparedness plan is highly recommended by FEMA and insurance companies. Model plans are readily available online, most of which define tasks along a hypothetical timetable (e.g. general preparation, during a watch, during a warning, during the storm and after the storm).
When combined, the following proactive efforts can lessen the impact, should one of your facilities lie in the path of a hurricane. Items 1-8 would be appropriate during the “off season”, with items 9-14 being prudent during storm watches and/or warnings.
- Facilities in hurricane regions should be evaluated by qualified professionals that can identify areas of risk exposure and recommend appropriate remedial work.
- Roof perimeters should be closely inspected, as wind uplift forces are greatest there. Check to ensure sheet metal flashings/copings, gutters, downspouts and wall panels are secure. Attempt to determine if any wood nailers or other substrates beneath roof edges are loose. Did the roof system receive enhanced fastening in the perimeter and corner zones during its installation? Provide reinforcement or repair of any areas with insufficient securement.
- If a facility is located in a potential flood area, have the roof drainage system evaluated to identify any areas where water could build up to dangerous levels should the storm sewer or other drain outlets become submersed. Where necessary, add overflow drains or overflow scuppers.
- Make wind resistance a key criterion when prioritizing roof improvements. A roof over a critical area might be a candidate for reinforcement or replacement when evaluated from the standpoint of windstorm resistance, even though it has a history of watertight performance.
- Check anchorage of rooftop units, piping, conduits, vents, ductwork, etc. Provide securement where lacking.
- Review your insurance policy to verify all buildings are listed. Check into flood insurance.
- Maintain photographic documentation of pre-storm conditions for use in the event of a future storm-related insurance claim.
- Establish agreements with repair contractors, cleaning services, and other suppliers in advance. Consider using companies outside potential hurricane areas, as local companies may be over-committed.
- Move all vital records and protect critical equipment, products and furnishings.
- Inspect roofs and remove debris. Tree litter, manufacturing byproducts, etc., can clog drains and should be included.
- Inspect HVAC units, making sure all access panels are securely attached. Inspect curb-mounted equipment for proper anchorage.
- Remove debris from drain strainers, scuppers, gutters, downspouts, overflow drains/scuppers.
- If downspouts empty around the foundation, consider adding temporary extension pipes to carry water away. Secure the pipes.
- Procure emergency roof repair materials, such as wet or dry roof cement, bentonite granules, reinforcing fabric, caulking, tarps, rope and duct tape. Extra buckets or trash bins are helpful for containing leakage.