The most expensive thing on a dealership roof is a wet showroom floor on a Saturday, and the second most expensive is a sheet of snow sliding onto a customer's car. Both are bid items. Showroom, service building and canopy all need protecting, and all three answer to the same 60 psf snow and 115 mph wind in the city's criteria. Send us the plans and the sheet. We return one scope per building, the alternates on their own lines and the work hours that keep the sales floor open.
The call: three roofs, three bids
A dealership is usually three buildings in one: a showroom with glass walls and a tall parapet, a service wing with large bay doors and exhaust, and a canopy or porte-cochere where customers drop off cars. Each roof is built differently, fails differently and runs on a different schedule.
Bid them apart. The showroom roof is the one customers see through the glass, so a leak there costs sales. The service roof carries rooftop fans, makeup air and often oil-laden exhaust. The canopy sheds snow onto the one place people stand. A single lump-sum price hides which roof is driving the cost and which can wait a season.
We hand over the three numbers and a core result behind each. If the showroom roof is dry and sound, spend the money on the service wing, where the fans and exhaust wear the membrane. If the canopy is the only leak, fix the canopy and hold the rest. A good bid gives the owner the option to spend less now and more later, and it says what each choice risks. A showroom roof that is dry today but ten years old belongs on next year's list, not this year's, and the core results are what justify putting it there.
What it costs: after-hours work, glass protection and the canopy
Showroom work means covering glass and floor, scheduling noisy phases before opening and keeping dust out of cars on display. Those are labor lines. The crane pick runs at dawn, and the staging area sits on a side lot, never in the customer row.
The canopy is a separate cost. It may need new decking, flashing and a drainage change so meltwater does not drip where customers stand. If the owner wants snow guards or heat cable above the drop-off lane, price them as alternates with the tradeoff in a sentence: guards stop the slide, cable melts a path, and neither fixes a heat-loss problem inside.
What the code sheet says: 60 psf and ice barrier at every eave
Ice barrier underlayment is required at every eave on the city sheet, and wet snow is dense enough that a drift against a tall showroom wall is a concentrated load on the lower roof.
The lower service roof beside a tall showroom takes that drift. It is the first place we check for sag, ponding and cracked flashing. A structural check on the service wing before any recover layer is a line item, and it is cheaper than a repair after the framing moves.
Wind adds its own number. A tall showroom wall with a glass face catches gusts and pushes them across the roof edge, where uplift is highest. Edge metal with continuous cleats and a tight fastener row at the perimeter costs little at install and a lot after a storm. We price the perimeter pattern as its own line, so the owner can see the cost of the 115 mph design speed.
Where it fails first: the showroom parapet and the service roof drains
The showroom parapet takes the longest wall exposure and holds drifts. Flashing at the glass wall base and the roof edge is the first to open. On the service wing, drains clog with grit and frozen debris, and rooftop fans sit on curbs whose flashing has been patched more than once.
A stain on a showroom ceiling tile points to the roof edge or the drain closest to it. We trace with a moisture reading and a hose test, then repair the detail. For fans and exhaust, rooftop equipment curbs and supports are rebuilt with taller flashing and proper support, so the next thaw does not find the same hole. Exhaust from an engine bay carries heat and oil vapor, and both age a membrane faster in a small zone around the fan. A protective pad or a more resistant sheet there is a cheap alternate with a long payback.
Alternates: white membrane, cover board and a heavier edge
A white single-ply sheet, such as TPO roofing, reflects heat and welds at the seams. A cover board adds protection from foot traffic and tool drops. A heavier edge-metal and fastener pattern answers the 115 mph design wind speed. Each is a line with a price.
We name what we would buy, then let the owner pick. A dealer with a lot in Hayden on US-95 and another in town can carry the alternates from site to site. The same cost logic applies to big-box retail roofing, where a large field and customer traffic work the same way, and to shopping center roofing, which splits one roof among many tenants. Dealers who share a lot with other retail near Riverstone should read their lease for roof responsibility before the bid goes out.
Schedule and snow window: no tear-off over a full lot
Open the roof only as far as the crew can dry in that day. Move the work zone away from the customer row. Book the job in winter for a June start, because dealerships cannot lose a spring sales season to a late start. A windstorm can arrive any night of the season, so open edges get tied down before the crew leaves.
If a leak appears during the season, our emergency roof repair response dries it in the same day. The permanent fix waits for a dry window, and the showroom does not close. Hold points go in the schedule: the deck inspection, the insulation layer and the final flashing walk. At each, the crew stops and the owner or an inspector looks before the next layer covers the work.
Closeout: a showroom roof file and a fall drain check
Handover includes drain, flashing and seam photographs, a dated punch list, a roof diagram marking each curb and fan, and product data for the membrane and edge metal. When a manufacturer's rep or an insurer asks what is on the showroom roof, the answer is already in the folder. A fall visit clears drains before snow. A spring visit checks the canopy and the parapet for ice damage. The file answers the next lender or buyer without a site visit.
Commercial Roofing Questions
Can the showroom stay open during a reroof?
Yes. We cover glass and floor, run noisy work before opening and dry in every day. The sales floor stays open. Display cars stay covered and the crane lifts material before the first customer arrives.
Who pays for snow sliding onto cars?
That is a risk question for the owner and the insurer. From the roof side, snow guards and a redirected drain cut the risk, and we price them as alternates.
Is heat cable worth installing at the canopy?
As an alternate, sometimes. It melts a channel but does not stop ice forming. Insulation and air sealing treat the cause.
How do we handle oil-laden exhaust on the service roof?
We check the area around the exhaust for staining and softening, clean it and add a protective pad where needed. A full or missing tray gets replaced.
What does the closeout file include?
Photographs, a punch list with dates and a roof diagram marking every curb and fan.