Navigating the Roofing Inspection: A Kansas City Homeowner’s Manual

In the Kansas City metro, a roof inspection isn’t just a cursory glance from a ladder. It is a technical evaluation of whether your home meets the specific International Residential Code (IRC) standards adopted by local jurisdictions—from the historic bungalows of Waldo to the newer builds in the Northland.

The Technical Baseline: IRC 2018 and 2021

Most municipalities in the KC area, including KCMO and the larger suburban districts, have transitioned to the 2018 or 2021 IRC standards. During an inspection, the primary focus is on "system integrity." This means the inspector is not just looking at the shingles you bought from local suppliers like ABC Supply Co. or Beacon Building Products; they are looking at what lies beneath.

The "Ice and Water" Mandate

Because Kansas City sits in a unique freeze-thaw climate zone, code requires an ice and water shield (a self-adhering polymer-modified bitumen sheet). Inspectors look for this membrane to extend from the eave's edge to a point at least 24 inches inside the exterior wall line. In neighborhoods with steep pitches, like those found in the Country Club District, this is the most common point of failure in a municipal inspection.

The Three Phases of Inspection

1

The Decking Evaluation

Before the first shingle is nailed, an inspection of the "deck" or sheathing is critical. In older KC homes, particularly in the Midtown area, we often find spaced board decking (1x6 or 1x8 boards). Current codes generally require a solid surface. If the gaps between boards exceed 1/8 to 1/4 inch, your inspector will require a re-deck with 7/16" OSB or plywood. This adds roughly $85 to $110 per "square" (100 sq. ft.) to the project cost.

2

Drip Edge & Flashing Verification

A major focus for Kansas City inspectors today is the drip edge. Per IRC R905.2.8.5, a drip edge is required at eaves and gables. It must be mechanically fastened and overlap at least 2 inches. Many "storm chaser" crews skip this to save $200 in material, but it is a "red tag" (fail) offense in KCMO inspections.

3

Ventilation Calculation

The inspector will verify the Net Free Venting Area (NFVA). The 1:150 rule applies here—one square foot of ventilation for every 150 square feet of attic floor space. In the humid Missouri summers, inadequate ventilation leads to shingle blistering, which can void your manufacturer warranty.

Mid-Roof vs. Final Inspections

Depending on your specific KC zip code, you may be subject to a "mid-roof" inspection. This occurs while the underlayment is visible but before the shingles are fully installed. If your contractor misses this window, the city may require "destructive testing"—literally tearing up new shingles—to prove the underlayment and ice shield were installed to code.

  • ✔ Chimney Cricket (if chimney width > 30")
  • ✔ Kick-out Flashing at wall intersections
  • ✔ Fastener count (typically 4-6 nails per shingle)
  • ✔ Valley lining (metal or high-temp membrane)

The Cost of Compliance

While basic inspection fees are usually included in your permit price, failing an inspection can result in a "re-inspection fee," typically ranging from $50 to $100 per visit in the Kansas City area. For homeowners, the real cost lies in the "code upgrades." If your insurance policy does not include "Law and Ordinance" coverage, you may be responsible for the cost of bringing an old roof up to these modern standards (like adding the ice shield or replacing decking).

When reviewing quotes, ensure your contractor has line-itemed these code requirements. A "flat rate" quote that doesn't mention the IRC 2018 drip edge or ventilation standards is a red flag that your inspection will likely fail.