Renew or Replace Your Commercial EPDM Roof: A Step-by-Step Guide

If your EPDM roof is aging and causing problems, this step-by-step guide will help you make the right decision.

Step 1: Commission an Independent Inspection

Before accepting any recommendation, commission an independent inspection from a contractor who offers both restoration and replacement. Request core samples at multiple locations and an infrared scan if the roof is large. You need objective moisture data — not a contractor's opinion formed on a visual walkthrough.

Step 2: Determine Wet Insulation Percentage

The core sample data reveals moisture levels in the insulation. If wet insulation is below 25% of the total area: renewal is viable. If above 25%: replacement is more cost-effective. This single data point drives the decision more than anything else.

Step 3: Assess Membrane Condition

If moisture qualifies for renewal, assess the membrane itself. Is it adhered (not significantly delaminated)? Are seams still bonded (even if leaking)? Widespread membrane shrinkage or delamination may prevent restoration even when moisture levels are acceptable.

Step 4: Get Proposals for Both Options

If renewal is viable, get proposals for silicone coating restoration ($2.50–$4.50/sq ft). Get a replacement proposal for comparison. In most qualifying cases, the cost difference is so significant that renewal wins clearly.

Step 5: Choose and Execute

For renewal: verify the contractor is manufacturer-approved, confirm the proposal includes wet insulation removal and replacement, and insist on a manufacturer warranty. For replacement: choose a system with a renewable warranty to avoid repeating this decision in 20 years.