Failed Flat Roof Rebuilt With White EPDM — East Denver
Project Overview
- Location: East Denver, CO
- Building Type: Residential Single-Family Home and Attached Garage
- Size: 2,500 sq ft
- Roofing System: Versico 115-mil white RapidLock EPDM over ½” HD cover board, two layers of 2.6” polyiso, and VapAir Seal 725TR vapor retarder
- Duration: 10 days
- Completed: November 2025
- Manufacturer: Versico Roofing Systems
- Warranty: 20-year Versico Roofing Systems warranty
Roof Condition
The home’s flat roof had been installed incorrectly by another contractor and was failing. The problems went below the membrane, so a new layer on top would not have fixed it. The roofing and the decking both had to come off.
- Flat roof system installed incorrectly by another contractor
- Failures extending below the membrane into the decking and joists
- Damaged roof joists requiring structural repair
- A coating or overlay would not fix the underlying problems
Evaluation & Approach
The problems went below the membrane into the decking and joists, so a new layer on top would not fix the cause. A full tear-off to the joists and rebuild of the complete assembly was the only way to address the structural and waterproofing failures.
Why This Approach
- Rebuilding the full assembly fixes the cause instead of covering it
- Air and vapor retarder stops interior moisture from entering the roof assembly
- Two staggered layers of polyiso provide continuous insulation with offset joints
- HD cover board gives the membrane a hard, impact-resistant base
- RapidLock attaches fleece-backed EPDM without bonding adhesive — no fumes, no temperature limits
- White EPDM reflects heat while keeping EPDM’s long service life and hail performance
Scope of Work
- Tear-Off and Joist Repair: Tore off the existing roofing system and decking. Repaired damaged roof joists with new 2x8 lumber.
- Batt Insulation and New Decking: Installed new batt insulation in the joist cavities and new plywood decking over the repaired framing.
- Vapor Retarder: Installed Versico VapAir Seal 725TR air and vapor retarder over the house and garage to stop interior moisture and air movement from entering the roof assembly.
- Polyiso Insulation: Installed two layers of 2.6” polyiso insulation with staggered joints for continuous insulation above the deck.
- HD Cover Board: Installed ½” Versico HD RapidLock cover board, mechanically attached, to provide a hard, impact-resistant base for the membrane.
- EPDM Membrane: Installed Versico 115-mil white RapidLock fleece-backed EPDM membrane — no bonding adhesive, no fumes, no temperature limits on installation.
- Edge Metal, Gutters, and Trim: Installed new 2x4 perimeter drip edge with EPDM cover strip detail, new pipe boots at all penetrations, 6” gutters with 3x4 downspouts and mesh gutter guards, and replaced approximately 50 linear feet of fascia and repaired soffit at the house and garage corner.
Result
Warranty: 20-year Versico Roofing Systems warranty
- Complete Assembly From Joists Up: New decking, insulation, vapor retarder, cover board, and membrane — every layer manufacturer-specified
- Watertight White Membrane: Versico 115-mil white RapidLock EPDM reflects heat while delivering EPDM’s proven hail and UV performance
- New Edge Metal and Gutters: New drip edge, 6” gutters, 3x4 downspouts, mesh guards, and fascia and soffit repairs at the corner
- Completed in 10 Days: 2,500 sq ft rebuilt from the joists up in ten working days with a 20-year Versico warranty