Built-Up Roof (BUR) Systems in Jacksonville, FL

Roof System

Jacksonville's older commercial inventory — Downtown office buildings, Riverside commercial blocks, San Marco retail, Northside industrial — carries a significant volume of built-up roofing installed between 1950 and 1990. We assess, repair, and replace BUR systems to current Florida Building Code requirements and document the correct transition path for each building.

Built-up roofing (BUR) — alternating layers of bitumen and reinforcing felt, typically three to five plies, topped with aggregate surfacing or a mineral cap sheet — dominated the Jacksonville commercial market from the post-World War II build-out through the 1980s. The Downtown Northbank corridor, the Riverside commercial district, the San Marco retail block, and the older Northside and Westside industrial parks contain significant BUR inventory that ranges from well-maintained 30-year-old systems approaching end of service life to neglected systems that have been patch-repaired beyond the point where further patch work is cost-effective.

BUR systems in good condition with dry insulation and sound deck are candidates for restoration — a compatible reflective coating over the existing aggregate surface extends service life 10-15 years at substantially less than replacement cost. BUR systems with saturated insulation, delaminated plies, or structural deck compromise require full replacement. The challenge with older Jacksonville BUR systems is that the insulation type common in pre-1980 construction — perlite board, wood fiber board, or fiberboard — is harder to assess for saturation than modern polyiso. We core-pull and field-verify before making the restoration-vs-replacement recommendation.

Florida Building Code's energy and wind requirements govern BUR replacement the same way they govern any roof type. A BUR replacement in Jacksonville must meet ASCE 7-22 130 mph design wind-uplift requirements, Florida Product Approval for the full replacement assembly, and Florida Energy Code reflectance requirements for Climate Zone 2. Restored BUR systems are evaluated under FBC's maintenance provisions rather than full replacement code, but we document the distinction clearly in the scope so building owners understand what they are committing to.

BUR Inspection and Core Assessment in Jacksonville

Assessing an older BUR system in the Jacksonville market requires more fieldwork than assessing a modern single-ply installation. Pre-1980 BUR systems used insulation types that absorb and retain moisture differently than polyiso — wet perlite board can feel dry to casual inspection but hold significant moisture that core analysis reveals. We pull cores in representative locations weighted toward low-slope areas, drain sumps, and any location where we see surface blistering, alligatoring, or active cracking.

Core analysis identifies the insulation type (perlite, fiberboard, glass fiber, or early polyiso), the moisture content of each insulation layer, and the deck condition underneath. Corroded steel deck underneath a wet perlite board layer is a common finding in Jacksonville buildings that have had decades of roof drainage problems — the deck can look structural but have lost significant section from corrosion. We inspect deck condition through the core pull location and recommend structural assessment when corrosion is visible.

Infrared scanning is an available diagnostic tool for larger BUR roofs where core-pulling every location is impractical. We use infrared as a secondary tool to identify wet zones that core verification then confirms. Infrared alone is not sufficient for a replacement decision in Jacksonville's climate — the high ground temperature during summer months creates thermal noise that makes some dry areas read as wet and vice versa. Core verification anchors the diagnosis.

BUR Transition: Restore, Recover, or Replace

Restore over existing BUR: When insulation is dry and surface condition allows adhesion, a compatible reflective coating — silicone or acrylic — bonds to the existing aggregate surface after preparation (typically a blower-clean and prime step). This approach adds reflectance that brings the system into Florida Energy Code compliance and extends service life without generating a demolition waste stream. The resulting system is not warranted under a new manufacturer warranty but is governed by the coating manufacturer's warranty.

Recover new membrane over existing BUR: When the BUR surface is deteriorated but the insulation is dry, a new single-ply membrane — typically TPO or EPDM — over a suitable cover board on top of the existing BUR is a legitimate scope. This approach generates no demolition waste, eliminates the cost of removing and disposing of the BUR aggregate, and produces a new manufacturer warranty on the new membrane layer. FBC's 25% rule applies: if more than 25% of the roof is recovered within 12 months, the full roof must be brought to current code.