Flat Roof Systems for Ann Arbor's Office Parks
Office space in this market spreads out rather than stacking up, from the Domino's Farms complex on Plymouth Road to the low-rise business parks scattered through Pittsfield and Scio Townships. Almost all of it sits under low-slope membrane roofing, most of it built in a handful of eras with a handful of system types, and most of it multi-tenant. We spend a lot of time here on coordination as much as membrane work, because a roof over a multi-tenant office building answers to more than one lease.
Office Stock Around Domino's Farms and Plymouth Road
The Domino's Farms office park and the buildings strung along Plymouth Road and Green Road carry a mix of 1980s and 1990s-era built-up and modified bitumen roofs that have gone through at least one recover cycle already, alongside newer TPO installations on more recently built or renovated space. Further south, the office and flex buildings around State Street and Eisenhower Parkway skew slightly newer but face the same basic question every low-slope office roof eventually faces: recover the existing field or tear off to bare deck. We answer that by core-sampling the existing assembly, checking for trapped moisture in the insulation, and being honest about whether a recover actually solves the underlying problem or just buys a few years before wet insulation forces the issue anyway.
Multi-Tenant Coordination
A single-tenant building answers to one facilities contact. A multi-tenant office building answers to a property manager balancing several leases, each tenant with their own sensitivity to noise, dust, and access disruption. Before we schedule a phase, we work through which suites sit directly under the section being worked, what hours are quietest for that tenant's business, and where staging and crane access can happen without blocking parking that multiple businesses share. A full roof inspection up front usually surfaces which tenants are most likely to notice water intrusion first, which shapes how we prioritize phasing.
We also build in tenant notification timing as part of the schedule rather than an afterthought, since a property manager coordinating five or six leases needs lead time to notify tenants before work starts overhead.
TPO and EPDM Choices for Low-Slope Office Roofs
Most office roofs in this market are straightforward candidates for either TPO or EPDM, and the choice usually comes down to the building's specific conditions rather than a blanket preference. TPO's heat-welded seams and reflective surface make sense on buildings with meaningful rooftop equipment density where seam integrity around multiple curbs matters most. EPDM's simpler installation and long field track record make it a strong option on buildings with a cleaner roof field and fewer penetrations, particularly where budget favors a system with a long history of predictable performance in this climate. We walk owners through both before recommending one, because the wrong system for the building's actual use is a worse outcome than either system installed correctly.
- Core sampling before any recover-versus-replace decision
- Tenant-aware phasing that respects shared parking and access
- TPO for equipment-dense roofs where seam welding matters most
- EPDM for cleaner fields where long-term field performance is the priority
- Fastening patterns matched to each building's actual wind exposure
- Drainage checked against real ponding history, not only design specs
Ballasted and Mechanically Attached Systems Over Occupied Space
Some of the older office park roofs in this area still carry ballasted EPDM systems, which have their own maintenance profile: stone ballast shifting over time, drains getting buried under displaced gravel, and root systems from wind-blown seed finding their way into the ballast layer. Where a ballasted system is still sound, we clean and reset ballast around drains rather than defaulting to full replacement. Where wind exposure or roof condition calls for a change, mechanically attached systems with fastening patterns engineered for the building's actual height and exposure category give a more predictable long-term result than continuing to maintain an aging ballasted field.
Freeze-Thaw and Ponding on Large Office Roofs
Large, flat office roofs are prone to ponding wherever the deck has settled slightly over the decades, and standing water that survives more than 48 hours accelerates membrane breakdown regardless of system type. Freeze-thaw cycling makes this worse in winter, when ponded areas freeze, expand, and stress seams that stayed sound through the rest of the year. We map ponding patterns across a roof visually and through drainage testing before recommending tapered insulation or additional drains, since guessing at a fix without confirming where water actually collects wastes the owner's money.
Questions Office Property Managers Ask
How do you minimize disruption to tenants during a reroof?
We phase work around which suites sit under each section, coordinate quiet hours with sensitive tenants, and build tenant notification lead time into the schedule so the property manager isn't fielding surprise complaints.
Should we recover the existing roof or tear off completely?
That depends on what core samples show. If the insulation is dry and the deck is sound, a recover often makes sense. If moisture has gotten into the insulation, a recover just delays a tear-off that's coming anyway.
TPO or EPDM, which is right for our building?
Buildings with dense rooftop equipment usually favor TPO's welded seams around multiple curbs. Buildings with a cleaner field and fewer penetrations are often better served by EPDM's simpler, long-proven field performance.
What causes ponding on a large flat office roof?
Usually deck settlement over the decades combined with drains that weren't sized or placed for how the roof actually sheds water. We map the ponding pattern before recommending tapered insulation or added drainage.
Can a ballasted roof be maintained instead of replaced?
Often, yes, if the membrane underneath is still sound. We clean and reset shifted ballast around drains rather than defaulting to a full system replacement when the underlying roof doesn't call for it.