Commercial Roofing in Downtown Flagstaff, AZ

Brick holds the edge. Snow loads the middle. Downtown Flagstaff, AZ is a district of masonry buildings. Fires led to an 1897 ordinance that put brick, stone or iron on every building in the business area. Older downtown roofs sit on those walls. Flagstaff's 90 to 97 inches of snow gives the parapets their drifts, freezes the drains and tests the decks underneath. We start every downtown roof with a sag check. Then we read the parapet, the drains and the flashing.

The District: What Sits Under the Snow

The Railroad Addition Historic District covers 17.8 acres bounded roughly by the Santa Fe tracks, Agassiz and Beaver Streets, and Birch and Aspen Avenues. It was listed on the National Register in 1983. The Weatherford Hotel, the Monte Vista Hotel, the Babbitt Brothers Building and the Riordan Building are among its historic commercial buildings. Along Santa Fe Avenue, each building fronts the tracks. Downtown declined after I-40 bypassed it in the 1970s and 1980s, and a 1987 master plan aimed to revitalize it. Roofs in a district this old differ in age and in the repairs they have taken. We read each one on its own.

Age shows in the details. Older commercial buildings can hide wood decks, layered repairs from different decades and sealed-up skylights. Each one holds water in its own way. A skylight that was covered but not removed is a flashing line with nothing below it. A deck repaired in one corner may carry less elsewhere. We list these items on the roof sketch so the next owner or crew inherits the knowledge.

Parapets: Where the Drift Piles Up

A masonry parapet turns a flat roof into a tray. Wind drops snow behind the wall, and the drift can run several times deeper than the open field. That load sits on the deck right where the roof is already weakest. When it melts, the water has to cross the drift and find a drain or a scupper. If those are iced shut, the water stands. We mark every drift line, check the deck below it and look at the parapet cap, the counterflashing and the mortar joints. Cracks at the wall top let meltwater into the brick and the interior.

Drift is not even. A tall neighboring building throws wind shadow across the roof, and a rooftop unit builds a long tail of snow. We walk the roof after the first big storm to see where the snow actually landed, then compare it with the plan. Roofs differ from year to year. A drift line that moved is a sign something else has changed, such as a new unit or a taller wall next door.

Structural Flags: Read the Ceiling First

Some parts of Flagstaff had 24.5 inches on the ground by March 2, 2023, after the storm of February 28. City officials reported collapses and gave owners a short watch list: sagging ceilings, bowing trusses, severe leaks. Those are not leak complaints. They are structural flags. In older buildings, the deck may be wood boards on old joists, carrying less than modern work. If you see a sag, a bow or a door that sticks, call a structural engineer before you call a roofer. The roofing scope follows the engineer's findings.

Drains and Scuppers: Keep Them Open

Old roofs often have few drains and old pipe. A clog in October is a pond in March. The fall walk clears each drain and scupper, flushes the line and tests the flow. We check the overflow openings in the parapet, since they are the only path when a primary drain freezes. A drain and scupper review pays for itself the first thaw. Heat tape on the drain line can help where freezing is chronic. We note which drains sit under drift lines, because they see the most water in the first warm spell.

Interior drain lines run through walls in many older buildings. A frozen or cracked line can flood a wall cavity without any sign on the roof. We check the visible pipe, the roof outlet and the cleanout, and we flag any line that needs a plumber.

Repair, Recover or Replace: The Options

Repair makes sense when the deck is sound, the insulation is dry and damage is local. We reseal parapet caps, reflash corners and patch the membrane. A recover may suit a flat roof with one dry layer, if the old deck can carry more. Replacement fits roofs with wet insulation, many layers or a failed deck. A core sample tells us which. A moisture scan narrows where to cut. In a historic district we also check what the building's character allows. Cornices, copings and decorative metal may need to be kept or matched, and the work is planned around them.

Winter work is limited to stopping water. We tarp, patch and clear drains, then date each temporary fix on the sketch. Permanent work waits for dry weather above freezing, usually late spring through early fall. Planning a year ahead lets the owner book that window before the rush.

Working Downtown: Access, Hotels and Shops

Downtown work happens among open businesses. Where hotels, shops and restaurants stay open, sidewalks carry foot traffic, and the railroad runs through. We plan hoisting and debris routes so sidewalks stay clear and entrances stay open. Noisy steps happen early. A hotel roof brings guest-room concerns, and a restaurant roof adds grease and exhaust. Cold-applied and welded systems reduce odor and flame risk near open windows. Occupied building reroofing goes best with a phased plan every tenant has seen.

The Recommendation: Check Before the First Storm

The September walk is the one that counts downtown. Freezing returns right behind it, in late September. Drains get cleared the same day. Check the parapet, the flashing and the edge metal. Write a shoveling plan with plastic tools. The address, the roof type and the last walk date are all we need to put the sag and drain checks on the calendar. Past Buffalo Park, East Flagstaff has the single-story mall, and the half-mile of old Route 66 in Southside and Mike's Pike has boxy industrial buildings. A repair that grows into a replacement has to meet the 2018 building and energy codes as the city amended them in 2019.

Rank the work by risk. A failed sag check puts a roof at the front of the line. Open parapet joints or drains that freeze move a roof to the second tier. Sound old roofs get a yearly walk. That order puts the money where load and leak risk meet.