Commercial Roof Replacement: What to Expect from Start to Finish

A commercial roof replacement is one of the larger capital projects you will undertake as a property owner. Knowing exactly what is going to happen from the moment you sign the contract to the day you get your warranty paperwork helps you plan, communicate with tenants or staff, and spot any contractor who is cutting corners. Here is the typical process for a Delmarva commercial roof replacement.

Phase 1: Pre-Project Inspection and Bid

Before we put a number on paper, we walk your roof completely, document everything with photos, and identify:

• Current membrane type and age
• Deck condition (probing for soft spots)
• Insulation condition
• All flashing details (parapets, curbs, drains, penetrations)
• Drainage patterns and any ponding zones
• Building access constraints

The proposal we write back is itemized: tear-off, deck repair allowance, insulation, membrane, flashing, dump fees, permit fees, warranty. No lump sums. You should be able to compare apples to apples with any other bid you get.

Phase 2: Permits and Scheduling

We pull all required commercial permits with Worcester or Wicomico County (or Sussex County in Delaware). Lead time on permits is usually 1 to 2 weeks. We schedule the project around your operational needs: peak business windows, special events, weather forecast.

Phase 3: Tear-Off

Existing roof gets stripped to the deck. Dumpsters staged, walkway protection set up if needed. On Delmarva commercial buildings, this is where most surprises happen: the layers underneath the old membrane often reveal more deck damage than was visible from above.

We photo-document everything we find and update the project scope if deck damage exceeds the original allowance. No surprise change orders without documentation.

Phase 4: Deck Repair and Insulation

Soft or rotted deck sections replaced. New insulation layer installed (typically polyiso boards) to meet or exceed local code R-value. Insulation joints staggered and taped per manufacturer spec.

Phase 5: Membrane Install

The membrane goes down per manufacturer requirements:

• TPO: mechanically fastened or fully adhered, seams heat-welded.
• EPDM: glued or ballasted, seams sealed with tape.
• PVC: similar to TPO with heat-welded seams.

Every seam is tested. We use seam probes to verify weld integrity, especially on TPO and PVC installs.

Phase 6: Flashing Details

All flashing terminations go in: parapet walls, HVAC curbs, drains, scuppers, vent penetrations, expansion joints. This is where most commercial roofs fail prematurely, so it is where we spend disproportionate time and attention.

Phase 7: Final Inspection and Warranty

Final walk-through with you. We document the finished roof with photos and provide:

• Manufacturer warranty registration (typically 20 to 30 years on membrane)
• Our workmanship warranty in writing (typically 5 to 10 years)
• Maintenance recommendations and schedule
• Final invoice with itemized completion

Total Timeline

• Small commercial (under 5,000 sq ft): 3 to 7 days of active work
• Medium commercial (5,000 to 15,000 sq ft): 1 to 2 weeks
• Large commercial (15,000+ sq ft): 2 to 4 weeks

Weather delays add time. Plan for some buffer in your scheduling.

Frequently Asked Questions

Can my business stay open during replacement?

Yes, in most cases. We phase the work, cordon off active zones, and clean up daily. Specifics vary by building type.

What if you find more damage than expected after tear-off?

We photo-document everything, communicate immediately, and provide a clear change-order with pricing. No surprise charges without documented justification.

How long is the manufacturer warranty?

20 to 30 years depending on membrane and installation level. Carlisle, Firestone, GAF Commercial, and Sika all offer multi-decade NDL (no dollar limit) warranties on certified installations.

Schedule a Commercial Roof Walk-Through

Thinking about a commercial roof replacement on Delmarva? G and Bros provides free walk-throughs and detailed proposals across Salisbury, Ocean City, and the entire Eastern Shore. Call 410-677-4975 or visit gandbrosroofing.com/contact. Also read: complete commercial roofing guide.