Repair failed roof flashing in McKinney, TX: wall terminations, curb corners, pipe boots and parapets traced to the entry point and rebuilt to match.
Tell us about the building and what you are seeing. We reply with the next practical step.
Counterflashing that has pulled away from a masonry wall is one of the quietest ways a roof starts to leak. The membrane field can be fine for years while the strip where it turns up the wall lets in a little water on every windy rain. In McKinney, TX, we treat flashing as the first place to look when a leak does not line up with a damaged field. The first check separates a contained detail repair from a larger scope: is the failure local, or is the termination failing along the whole wall?
The city names Historic Downtown and several highway-oriented districts among its retail areas, and older storefronts there need a different access plan and phasing than the larger retail properties. The repair follows the wall in front of us, whatever the building.
A facility director with a stain on a ceiling and a roof that looks fine from the ladder needs something specific. We give that person a marked photograph of the failed detail, the reason it failed and the materials that will replace it, so the work order says exactly what is being done.
We inspect every flashing, not only the one near the stain. Wall terminations are checked for height, termination bar condition, sealant and fastener spacing. Curb flashings are checked at the corners, where the membrane is folded or cut and where leaks often begin. Pipe boots are checked for cracked rubber, loose clamps and failed sealant. Parapets are checked for open coping joints and loose caps.
Corners deserve extra time. An inside corner at a curb needs a formed or welded piece, and a field-folded corner without reinforcement splits under thermal movement. In summer, a dark roof runs far hotter than the air, and the daily swing from hot afternoon to cool night works every corner.
Penetrations multiply over time. Antennas, conduit, gas lines and sensors are added by other trades, and not every one is flashed properly. A skylight and penetration flashing review lists each opening with its condition. Some have a boot, some have sealant only, and sealant alone does not last.
A flashing repair opens the roof at its most vulnerable line. Before cutting, we confirm the interior below, protect equipment and ceiling, and agree on how far the work zone extends. If the building is in an occupied shift, we plan the sequence so the opening is closed the same day.
Temporary protection is built into the plan. Sealed covers, tape-down membrane and caulked edges hold until the permanent detail is ready. We photograph each stage, so the facility director can follow what was opened, what was dried and what was closed.
When the entry point is not clear, a leak trace narrows the source before cutting. Water can travel along a deck flute or beneath insulation, and the visible stain is often a long way from the opening. We start at the ceiling mark and work outward.
A re-seal is appropriate when the flashing is intact and the sealant has aged. We clean the surface, remove old sealant, prime where needed and apply a compatible product. It is quick and inexpensive, and it is temporary if the underlying detail is poor.
A rebuild replaces the flashing material and its attachment. We cut out the failed membrane or metal, install new base flashing at the correct height, add a termination bar or counterflashing and seal the top edge. On single-ply roofs the new flashing is welded to the field sheet. On bituminous roofs, plies are adhered or torched in compatible layers.
Replacement of the whole termination is needed when the wall is deteriorated, the flashing height is below the minimum, or the surrounding membrane is too aged to bond. The repair boundary lands on sound material, not on brittle sheet. McKinney lists the 2024 International Building Code and related existing-building and fire codes among its adopted editions, so the building official can confirm what applies when a flashing project grows. For parapets, edge metal and coping often needs replacement in the same visit.
Adhesives, sealants and welds have temperature and dryness requirements. Summer highs near 96 degrees in July and August, per the DFW normals, mean the roof surface can be too hot to handle membrane safely in the afternoon. We start early and plan to close each detail by midday where possible.
Spring is the other constraint. Spring storm lines move fast in this region, so we never leave a termination open when one is forecast. A weather hold is better than a half-finished corner.
Sequencing matters on roofs with many flashings. We work from the high side to the low side so that water running during the job does not enter a new opening. At sites near US 75 or the SH 121 districts, tenants and deliveries are settled before a lift goes.
The flashing must match the roof. Thermoplastic roofs use welded flashing of the same material. Rubber roofs use compatible sheet with adhesive or tape. Modified bitumen uses flashing plies bonded to the field. Metal roofs use formed trim and sealants rated for the metal. Mixing materials, such as putting asphalt mastic on a single-ply sheet, can damage the membrane itself.
Movement is the common cause of failure. A rigid sealant bead cracks. A flashing glued to a wall without a termination bar peels as the wall shifts. A metal flashing without expansion joints buckles. If the cause is movement, the fix must allow for it with a flexible detail. If the cause is water standing at the wall, the drainage is corrected as well, as with ponding water.
Wind can reopen a detail that was sound. After a gust event, a wall termination or coping may lift, and the lifted edge is reset the way it would be on any wind-damaged roof. We test the finished flashing by probing edges and inspecting laps.
The record for a flashing repair is a map: each detail located on the roof diagram with before and after photographs and the material used. We include termination height and fastener spacing for walls. The next facility director can then see what was done and where.
A follow-up after the first heavy rain confirms that the leak is gone. Properties in Frisco or Allen follow the same mapping method, and facility teams with several buildings can add flashing checks to a preventive maintenance route.
Tell us where water appears, your operating hours and how the roof is reached. We will trace the failed detail and sequence the repair around the workday.
Short answers to what owners and facility managers ask before a roof visit.
Only as a short-term measure. Caulk can slow a small leak where the flashing is sound. If the flashing has lifted, cracked or split, a rebuilt detail is the durable fix.
The patch usually treated the symptom. A corner under movement needs a formed piece or reinforcement. We find why it failed before choosing the repair.
High enough that water cannot get behind the top edge. Codes and manufacturer details set the minimum. We measure existing heights and report any that fall short.
Sometimes. If the flashing runs behind the unit or the curb is damaged, the unit may need to be raised or shut down. We coordinate with the mechanical contractor to keep the downtime short.
We close the opening with a temporary cover and hold the permanent work for the next dry window. No detail is left open overnight when rain is expected.
Send a question about the building and we will reply. Or call 555-555-5555.
