What to Expect During a Commercial Roof Replacement
A commercial roof replacement is a significant investment and a major project. Understanding what happens at each stage helps you prepare your building, communicate with tenants, and ensure the project runs smoothly. Here's a comprehensive overview of the replacement process.
Phase 1: Assessment and Planning
Before any work begins, a thorough assessment determines the scope of the project.
- Complete roof inspection including core samples to assess decking
- Identification of problem areas and special requirements
- Material selection based on building needs and budget
- Permit acquisition and HOA/municipality approvals if needed
- Scheduling to minimize business impact
Phase 2: Site Preparation
The week before work begins, preparation protects your property and ensures efficient operations.
- Notification to building occupants about project timeline
- Establishment of material staging areas in the parking lot
- Protection of landscaping and building entrances
- Setup of safety equipment and roof access
- Coordination with any rooftop equipment providers
Phase 3: Tear-Off
The existing roof system must be removed down to the deck in most cases. This is the noisiest and most disruptive phase.
What to Expect
Tear-off typically generates the most noise and debris. For a 20,000 square foot roof, tear-off usually takes 2-4 days depending on the number of existing layers and deck condition.
Phase 4: Deck Inspection and Repair
With the old roof removed, the underlying deck is fully visible. Any rotted, damaged, or deteriorated decking must be replaced before the new roof goes on. This is also when additional insulation is typically added to improve energy performance.
Phase 5: Installation
The new roofing system is installed in layers: insulation, cover board (if specified), and the membrane. For TPO and PVC systems, seams are heat-welded. Flashings are installed around all penetrations and edges.
- Insulation installation (typically polyiso boards)
- Cover board installation for puncture resistance
- Membrane installation with welded or adhered seams
- Flashing installation at walls, curbs, and penetrations
- Installation of edge metal and drip edges
Phase 6: Final Inspection and Cleanup
After installation, the project isn't complete until final inspections are passed and the site is cleaned.
- Contractor quality control inspection
- Manufacturer inspection (for warranty certification)
- Municipal inspection for permit closeout
- Complete site cleanup and debris removal
- Final walkthrough with building owner
Timeline Expectations
A typical commercial roof replacement takes 2-4 weeks for a 20,000-50,000 square foot building. Weather delays can extend this. Your contractor should provide a detailed schedule and keep you updated on progress.
Minimizing Disruption
Most commercial roof work can happen while the building remains operational. Work hours can sometimes be adjusted for noise-sensitive businesses, and experienced crews know how to minimize impact on daily operations.
