How to Easily Increase the Slope of Your Commercial Roof?

Flat commercial roofs require adequate slope to drain water properly. When slope is insufficient, ponding water develops — and ponding accelerates membrane wear, adds structural load, and voids most warranties. Here's the easiest way to add slope.

Why Traditional Methods Are Difficult

Traditional slope correction requires: removing the existing membrane, installing tapered insulation boards at varying thicknesses (a precise, labor-intensive process), and re-installing the membrane. This is expensive, time-consuming, and highly disruptive — effectively a full tear-off project.

Spray Foam: The Easy Solution

Spray foam is fluid-applied and can be built up at any thickness in any location. To add slope, the contractor applies more foam in low areas and feathers it toward drains or roof edges — creating positive drainage without any structural work. The foam itself becomes the new roof surface (with topcoat), so no separate membrane installation is required. The entire slope correction happens in the same application as the waterproofing.

Precision Slope Design

Before installation, a spray plan is developed that specifies foam thickness at each point of the roof to achieve the desired drainage pattern. Depth probes verify that specified thicknesses are being achieved throughout application.

Cost-Effective at Any Scale

Because foam application scales efficiently with crew size and equipment, slope correction on large commercial roofs is completed in days to weeks at $4–$8/sq ft total — far less than a structural slope correction combined with a new roofing system.