A distribution center roof fails at the drift line first. Long, flat spans collect snow wherever a wall, a unit or a dock canopy breaks the wind. That snow melts into drains that may be frozen. In Flagstaff, AZ, 90 to 97 inches of snow in a normal winter puts those two facts at the top of the maintenance calendar.
Get the roof walked before the first heavy storm. Tell us the building, how many docks it has, the roof type and the last time anyone went up. We set the sag and drain checks around your shipping days.
Distribution buildings are built for clear space inside. That means long spans and few columns. It also means the roof carries snow with little help from interior supports. The one-day record in town is 35.9 inches, logged on February 21, 2019. Roofs came down across the city after the late February 2023 storm. Its warnings started with sagging ceilings and bowing trusses.
Watch for those signs from the warehouse floor. A bowed truss over a rack aisle is an urgent call, not a roofing job. We report it to the owner and the engineer, then adjust the roof plan around what the engineer decides.
Weight is only half of it. Sliding snow is the other half. A heavy slab can release from a sloped section and land on a lower roof, a truck or a person. We look for lower roofs under higher ones and add snow retention or a protected zone where that happens. A map of these spots goes in the building file.
I-17 ends at I-40 in Flagstaff, and the BNSF Southern Transcon runs east-west through town. Industrial land in Flagstaff runs along I-40 and I-17. Bellemont, about 11 miles west-northwest on I-40, hosts the Camp Navajo industrial park. Nestle Purina PetCare and Joy Cone are among the major employers in Flagstaff.
Roof systems on these buildings vary. The first job on any walk is to name the system on top. Built-up, metal and single-ply all call for different checks. A plain warehouse has fewer moving parts, and a cold storage building adds vapor trouble to the snow.
Start at the dock edge. Trucks back in, canopies project and parapets rise. Snow drifts behind each. Deep drifts load the deck and bury drains. We measure drift lines in fall, mark them on the plan and flag any deck that already sags.
Then check rooftop units. Each has a curb, a flashing and a shadow of drifted snow on its leeward side. Look for cracked sealant, loose panels and ice-damaged condensate lines. A unit that leaks into the sprinkler system or a rack aisle is a worse problem than a drip on a pallet.
Look at the sprinkler and fire lines near the roof too. Water that freezes in a pipe below a cold roof can burst it, and a leak above a pipe adds to the risk. Insulation that has gone wet loses value fast, so a cold spot on a ceiling is worth a moisture scan. An infrared moisture survey shows it from above in one pass.
Of Flagstaff's 20 to 22 inches of yearly moisture, roughly a third arrives with the July and August monsoon. A monsoon cell can drop a hard burst of rain on a dry roof in minutes. Winter snowmelt asks drains to carry water that is partly frozen.
Keep roof drains and scuppers clear in both seasons. Clean them in fall. Check them after the first thaw. Add overflow scuppers where the main drain can ice over. Water that cannot leave will find the lowest edge detail and use it.
Freeze cycles arrive early. The first hard freeze comes in late September, and the coldest reading on record is minus 30 degrees F. Sealants and flashings that were fine in summer stiffen and crack in the first hard freeze. Walk the roof in fall, and walk it again after the first deep cold. Mark any joint that has opened.
Roof work should not block docks. Plan staging away from truck courts. Keep fire lanes open. Schedule loud work for shifts when the floor is quiet. We close the roof in at the end of each day, so an overnight storm does not meet an open deck.
For snow removal, name who goes up and what they may use. Plastic shovels. No scraping to the sheet. Clear drains and drift areas first. A roof rake handles low edges. Each person on a snowy roof is tied off and has a clear path down.
Tell the dock supervisor and the security desk before roof work starts. Crews badge in, park where agreed and carry no loose material near truck lanes. A short daily briefing keeps everyone clear on what is open.
If the deck is sound and insulation is dry, repair the seams, flashings and edges. If wet insulation covers wide areas, plan a commercial roof replacement. A recover can work where the existing roof tests dry and the deck can carry another layer, but a snow-heavy site has less margin for added weight.
Moisture surveys and cores decide. Single-ply membranes with welded seams suit large, flat roofs. Add cover board where foot traffic is heavy. In snow country, specify a sheet and an attachment that tolerate cold, movement and ice.
Warranty paperwork matters. Many membranes carry terms on repairs and snow removal. Read them before work starts, log each repair and keep the file. If a roof is out of warranty, the same records still help with insurers and lenders. Our roof condition reports give you a dated baseline for each building.
Owners with several buildings near Butler Avenue and Lone Tree Road and on the I-40 corridor should rank roofs by span, age, drift exposure and what is stored below. Spend on the worst first. Put a fall walk and a post-thaw check on the calendar every year. Phone us before the first storm, and have the address and the last walk date ready.
Look for sagging ceilings, bowing trusses, doors that stick and new cracks. The city listed them following the February 2023 storm. On seeing any, stay off a roof that looks unsafe, clear snow only to a written plan, and phone an engineer along with us.
Clean them in fall, check them after each major thaw and add overflow scuppers where the main drain can ice over. Heat tape on drain lines helps in exposed spots. Mark the drains on the roof plan so a snow crew can find them.
Yes. Work in sections, stage materials away from docks and close each section in daily. We agree on quiet shifts for loud steps. Racking and sprinkler zones under the work get extra protection.
They do. Units block wind, so drifts form beside them, and their curbs are leak points. Check sealant and flashing in fall and clear drifted snow from the curb after each storm.
Once wet insulation covers a wide area, seams open in rows or the same section keeps failing, replacement is cheaper than another repair. Moisture mapping plus a handful of cores tells you how large the wet area is. Get both before you decide.
Browse the services, roof systems and building types we work with across Flagstaff and nearby Arizona communities.
A walk of the roof with photos, findings and a written scope.
Active leaks, storm damage and blocked drains get a fast response.
Roofing across Flagstaff and nearby Arizona communities.