Emergency Roof Repairs
1. General
Emergency repairs may be required after severe weather because leakage into a building can occur at any time (nights, holidays, weekends, etc.). Caution: It is generally not advisable to attempt roof repairs until after the severe weather has ceased, due to the danger of high winds and the possibility of a lightning strike. Caution should be exercised when inspecting a roof after there has been severe weather, or when there is suspect damage to the roofing assembly, because storm damage may have left the roof in a hazardous condition. If the roof condition is questionable, have a professional roofing contractor perform the inspection and necessary repairs. In the event a professional roofing contractor is not available, and to minimize damage to the interior building finishes and contents, emergency repairs may be performed.
Emergency repair procedures should be as simple as possible so they may be performed safely by non-roofing professionals. These repairs should be considered temporary. Permanent repairs should be made by a professional roofing contractor as soon as weather permits.
If the roofing system is under a manufacturer's warranty, the roofing material manufacturer, and the installing contractor should be contacted as soon as possible.
The following are emergency repair guidelines that may be performed by non-roofing professionals, or by professional roofing contractors.
2. Leak Repair Procedures
There are too many different types of roofing membranes to tailor emergency repair procedures for each. However, if literature cannot be located and/or if procedures are not detailed for emergency repairs, the following guidelines are suggested:
Remove excess water from the roof: Check roof drains and scuppers to be certain that they are open and functional. A frequent cause of roof leakage and roof collapse is excessive ponding on the roof surface due to clogged drains and/or scuppers.
Caution should be exercised when clearing debris from drains. Significant suction forces can be created by draining water, which can suck tools, hands, or arms placed within these vortices quickly into the drain.
Locate the source of a leak: In attempting to determine the source of a leak, locate the point on the roof surface above the area of leakage in the building interior. From this point, first check the condition of rooftop mechanical equipment, then check all flashings at terminations and penetrations. Second, if the system is ballasted remove ballast from the immediate leak area, then check the membrane surface for cuts, splits, or punctures. Finally, check the seams (laps) in the roofing membrane.
NOTE: In many cases, it can be extremely difficult to locate the source of a leak on a roof membrane that has been installed over insulation placed on a structural concrete deck, or over an existing membrane or vapor retarder. If the source of a leak into the building cannot be readily located, the owner or building maintenance personnel may have no recourse except to control the spread of water until a professional roofing contractor can be contacted and arrives at the site.
Perform emergency repairs: Once the source of a leak is located, the materials and procedures which will cause the least amount of damage to the roofing membrane should be chosen. Please refer to the following list of suggestions to perform emergency repairs by roofing system type.
Plastic Roof Cement - This method is recommended for use on all Built-Up-Roof systems and Modified Bitumen BUR and Single-ply systems.
An emergency patch can be made using plastic cement and fabric or roofing felt. Permanent repairs should be made as quickly as possible.
NOTE: If used on single-ply systems, this type of repair may require a larger section of single-ply membrane (and perhaps the insulation) to be removed prior to the permanent repair in order to ensure that any of the existing membrane contaminated with plastic cement is no longer present.
Plastic cement is a trowel-grade product. It is available in "rain patch" or "wet patch" grades, which are somewhat easier to apply to wet or damp surfaces. Avoid the use of a liquid or pourable asphalt repair products. Liquid products do not usually work well and most often only hinder a roofing contractors attempt to locate the leak source while performing temporary or permanent repairs.
Prior to making emergency repairs to existing gravel or granule surfaced roofing systems – Remove all loose gravel or granules from the membrane surface. Scrape (spud) embedded gravel/granules and surface asphalt to the membrane. For ail smooth surfaced B.U.R. systems including Modified Bitumen single ply, smooth surfaced B.U.R., Cap Sheet B.U.R. Composition Shingles etc., clean the surface of all dirt, dust and debris.
After the surface has been prepaired, and making sure that the area to receive the repair is clean and dry, apply a trowel grade asphalt plastic cement to extend beyond the area of repair approximately six (6") inches. The plastic cement should be applied in a continuos application over the membrane split, puncture, hole etc. Work the material into the membrane by applying a constant pressure while trowling.
NOTE: You can test the adhesion of the plastic cement to the membrane by laying the trowel flat on fop of the applied plastic cement surface and lifting. If the plastic cement lifts with the trowel, and exposes the membrane, it needs to be worked into the membrane better. After applying the first layer of plastic roofing cement to the membrane, embed a strip of fiberglass reinforcing fabric. Over the embedded fabric, trowel an additional layer of plastic roof cement to cover all exposed fabric. The fiberglass fabric acts to reinforce the plastic cement and can greatly extend the life of the repair. Some larger repairs can be covered with a additional layer of Type IV fiberglass felt set into a continous layer of plastic roofing cement.
Sealant & Roof Tape - This method of repair can be used on most smooth surfaced systems including Built-Up-Roofing systems, but is suggested for use on Single-Ply systems such as E.P.D.M. or PVC Thermoplastic.
To make emergency repairs using a sealant or roof tape membrane, start by cleaning the membrane surface with alcohol or a household cleaning solution, such as window cleaner. Then wipe the surface with a clean cloth and "splice cleaner" or white gas (use rubber gloves and proper skin protection).
After the membrane has been cleaned, apply a butyl or polyurethane sealant (caulking), or roof tape to the damaged roofing material. (Note: The surface must be clean for the repair material to adhere.) When using roof tape, pressure should be applied over the entire surface of the tape to ensure adhesion.
Sealants are available at most hardware, builders supply and home discount stores. A variety of roof tape products are also available. These products typically have a release paper on the backside and are a few inches wide. Roof tape products are also available through membrane manufacturers, roofing materials distributors, and roofing contractors.
Duct Tape - This method of repair is recommended for PVC (Thermoplastic) systems only.
Make a temporary patch for the roofing membrane using common duct tape. (Note: The surface must be clean and dry in order for the tape to stick. Cleaning guidelines are described in the "Sealant and Roof Tapes" section.)
3. Storm and Wind Damage Repair Procedures
Protect the interior: Control the spread of water in the interior by collecting the water in containers or by using plastic sheeting to protect the building contents.
If roof damage is observed during a storm, it is generally not advisable to attempt repairs or damage control until after the storm because of the danger of high winds and the possibility of a lightning strike.
In some instances, however, repairs during a storm may prevent or minimize further wind damage. For example, if a loose metal edge flashing is observed, securing it during a storm may prevent subsequent lifting, peeling, and blow-off of the membrane. If work is performed during a storm it should be done by a professional roofing contractor at his discretion. Work should not be performed during high winds or electrical storms. If a professional roofing contract is not available, work should not be undertaken unless wind speeds are moderately low and electrical storm activity has ceased.
Following the storm, loose debris on the roof that could be blown off in subsequent storm should be removed.
Because some roofs are in a hazardous condition after wind damage, debris removal should be performed by a professional roofing contractor if one is available within a reasonable time period.
Different types of attachment methods require special considerations, as discussed in the following guidelines:
Ballasted Systems: After high winds, the roof should be inspected to determine if ballast (aggregate or pavers) has been scoured (scattered), leaving areas of bare, unprotected membrane. If so, the exposed membrane should be inspected for open seams, punctures, and tears from flying debris (from rooftop mechanical equipment or from adjacent buildings). Membrane damage should be temporarily repaired before redistributing the ballast.
Temporary repairs made to the membrane should be marked on a roof plan to aid in locating them for later permanent repair. Except for areas less than 50 square feet (e.g. five feet by ten feet), inspection and permanent repairs should be performed by a professional roofing contractor.
Temporary Ballast: On ballasted single ply systems, bare areas greater than 50 square feet should be temporarily ballasted using sandbags, tires, concrete blocks, or concrete pavers. When applying temporary ballast, use caution to avoid overloading the structure.
If lightweight concrete pavers were used for the ballast and were displaced, use concrete blocks, heavy concrete pavers, or sandbags to achieve a minimum load of about 40 pounds per linear foot around the perimeter of the bare area. (The width of the temporary ballast around the perimeter to achieve the 40 pound load will depend on the weight of the ballast being used.) Place the temporary ballast on top of the remaining lightweight pavers to provide temporary protection against further wind damage until permanent repairs are made. In conjunction with setting temporary ballast of 40 pounds per linear foot around the perimeter of a bare area, also apply temporary ballast to secure the membrane when the bare area exceeds 50 square feet.
In some instances, insulation boards below the membrane are displaced. Displaced boards should be repositioned prior to final redistribution of ballast. If membrane cutting is required to reposition the boards, it should be performed by a professional roofing contractor. When bare areas exceed 50 square feet or when ballast is blown off the roof consult with the manufacturer because, in either of these cases, design enhancements may be advisable.
Mechanically Attached and Adhered, Single-Ply and Modified Bitumen Systems:
After high winds, the exposed membrane should be inspected for damage from flying debris. If fasteners have backed out or popped up and punctured the membrane, or if debris has punctured or torn the membrane, temporarily repairs will be needed.
Mechanically attached membranes should also be inspected to determine if any batten bars or fastening plates were uplifted, or if the membrane has separated from them. Likewise, fully adhered membranes should be inspected to see if they separated from the substrate. If the membrane is unattached from the substrate or fastening system, and the area exceeds 50 square feet, temporary ballasting should be performed as described previously under "Ballasted Systems."
If any of the above conditions are observed, a professional roofing contractor should make the permanent repairs.
If a mechanically attached membrane is observed billowing, consult with the manufacturer or the installing contractor. While some billowing may be normal, an excessive amount would indicate that design enhancements may be advisable.
If all or a portion of the membrane is peeled back, the building is vulnerable to water infiltration. In some instances, it is possible to reposition the membrane to provide temporary protection. Repositioning should be performed by a professional roofing contractor if one is available within a reasonable time period. After repositioning, the membrane should be fastened at the perimeter, the damage repaired, and temporary ballast installed.
If membrane is too damaged to be repositioned for temporary protection, replacement material will be needed. If a professional roofing contractor cannot provide temporary or permanent roofing service within a reasonable time period, it may be necessary to utilize large tarps or sheets of polyethylene secured at the perimeter and temporarily ballasted as previously described.
4. Installation of New Penetrations or Equipment
One of the most common causes of leakage is the improper installation of new roof penetrations or equipment. To avoid roofing problems associated with new penetrations or equipment, consult with a local roofing contractor qualified to apply the type of roofing system in place, to recommend temporary tie-in steps prior to the installation of rooftop penetrations or equipment. This would include such items as TV Antennae. sign or equipment supports, skylights, plumbing soil stacks, HVAC equipment, and electrical conduits.
If the roof system is under warranty, the name and telephone number of the roofing membrane manufacturer should be written down and kept in a safe place for future reference. Notification prior to installation will allow the contractor or manufacturer to recommend how to incorporate the new penetration or equipment and how to protect the membrane warranty, if one exists.
The permanent addition of penetrations or equipment to the roofing system should be undertaken by a professional roofing contractor qualified to perform such work. The name, address, and telephone number of a roofing contractor qualified to perform the work can usually be obtained from the roofing membrane manufacturer, or RoofHelp™, if the original roofing contractor is not available. Improper installation of penetrations or equipment may void the roof warranty. If the building maintenance person is forced to install temporary flashings, set the flashing flange(s) into a continuous layer of plastic roofing cement and follow the procedures set forth above.
5. Permanent Repair Requirements
The function of flashings is to provide a watertight junction between roofing materials and roof projections or other parts of the structure, and between roof sections. Flashings should be designed to furnish service for at least as long as the materials used in the field of the roof. Flashings are the most vulnerable part of any roof. Their importance and the importance of maintaining them properly cannot be overemphasized.
