Modified Bitumen & Built-Up Roofing in Winchester, KY

Modified Bitumen and Built-Up Roofing in Winchester, KY

Long before single-ply took over, commercial roofs in Central Kentucky were built-up asphalt and, later, modified bitumen. A great many buildings in Winchester and the surrounding towns still have them, and they are perfectly serviceable systems that fail in predictable, repairable ways.

What you probably have

Built-up roofing is the classic multi-ply asphalt and felt system, often surfaced with gravel. Heavy, durable, and hard to find a leak in because of that gravel surfacing.

Modified bitumen is asphalt reinforced with polymer, applied in sheets — torch-applied, hot-mopped, cold-adhered, or self-adhered. Usually one or two plies, frequently with a granulated cap sheet.

How they fail

• Seam and lap separation, particularly on older torch-applied work
• Blisters and ridging where moisture or air got trapped between plies
• Alligatoring — surface crazing as the asphalt oxidises and loses flexibility
• Granule loss on cap sheets, exposing the asphalt to UV
• Flashing failure at curbs, parapets, and penetrations
• Ponding water accelerating every one of the above

They repair well

This is the genuine advantage of asphalt systems: they are repairable with compatible materials, and a competent repair blends into the existing roof rather than sitting on top of it as a patch.

That means a mod-bit or BUR roof with life left in it is usually worth maintaining rather than replacing, and a roof near the end can often be restored with a coating instead of torn off. See roof coatings.

A note on torch work

Torch-applied modified bitumen involves open flame on a roof, and it is the single highest fire-risk activity in commercial roofing. It requires proper procedure — fire watch during and after work, extinguishers on the roof, and care around parapets, walls, and anything combustible in the assembly.

Where a building or its contents make torch work inappropriate, cold-adhered and self-adhered systems achieve the same result without flame, and we will recommend that rather than manage a risk that did not need taking.

Common questions

For region-specific guidance, the Clark County Cooperative Extension Service publishes local horticulture and home-maintenance resources for property owners here.

How do I know if I have BUR or modified bitumen?

A gravel-surfaced roof is almost certainly built-up. A smooth or granulated sheet in rolls with visible laps is generally modified bitumen. A photo usually settles it.

Are blisters a problem?

Not always. Small, stable blisters are frequently left alone; large ones, ones in traffic paths, and any that have broken open need attention. Cutting open a sound blister can create a leak that was not there.

Can an asphalt roof be coated instead of replaced?

Often yes, if the substrate is sound and dry. That is one of the strongest cases for restoration coatings. See roof coatings and maintenance.

Is torch application safe on my building?

It can be with proper procedure, and sometimes it is the wrong choice regardless — occupied buildings, combustible walls, or sensitive contents. Cold-applied alternatives exist and we will say when they are the better call.

Related: roof coatings · roof replacement · membrane comparison. Back to Winchester Commercial Roofing.

Winchester Commercial Roofing · Serving Winchester, Mount Sterling, Paris, Lexington & Clark County, KY · Call or text (859) 310-1209

Last updated August 2026

Related reading: Built-up roofing vs. single-ply — which is right for my building?