This example is made up, but the pattern is common in older masonry buildings: a roof that looks fine from below, an internal drain that has been slowly clogging, and a short, intense storm. The building materials, not just the water, shape every decision that follows.

The situation

Illustrative example. Not a real job or customer.

A hypothetical four-story brick warehouse in LoDo, converted decades ago to offices, has a flat roof with internal drains. During a late-afternoon thunderstorm with small hail, debris blocks one drain. Water ponds, rises over a flashing, and runs down inside an exterior brick wall. On the third floor a design firm finds water streaming down exposed brick, across the original timber floor and onto the ceiling below.

  1. The building manager sends the roofer to clear the drain and temporarily seal the flashing once lightning has passed.
  2. Tenants move drawings, computers and models away from the wet wall.
  3. The restoration contractor extracts water from the timber floor and checks the ceiling and floor below.
  4. Rather than tearing out, the contractor documents the brick, timber and plaster conditions and sets up controlled dehumidification.
  5. Moisture readings are taken in the brick and timber at marked points and compared with a dry wall elsewhere in the building.
  6. A modern drywall partition built tight against the brick is removed because it is trapping moisture.

The brick and timber dry over a longer period than a drywall office would, but without cracking or checking. The original materials stay in place. The roof drain is added to a quarterly maintenance list, and the flashing is repaired permanently after checking whether exterior work needs historic review.

Two ways this could have gone

Rushed response

  • High heat to dry fast, risking timber checking and mortar damage.
  • Removing plaster that could have been saved.
  • Exterior flashing replaced without asking about historic district review.

Measured response

  • Controlled drying with readings at depth.
  • Only failed or moisture-trapping material removed.
  • Exterior repairs coordinated with Denver Landmark Preservation where required.

Follow-up for the building

  1. Roof drain maintenance

    Add internal drains and overflow scuppers to a regular cleaning schedule, with extra checks before storm season.

  2. Parapet and flashing survey

    Have the roofer review all flashings, not just the one that failed.

  3. Tenant awareness

    Ask tenants on top floors to report ponding sounds or drips during storms right away.

General information for Downtown Denver, not a quote or professional advice. In an emergency, call 911.