Roll Roofing Products, Asphalt Roll Roofing Materials, Asphalt Roll Roofing Defects, Asphalt Roll

Roll Roofing Products, Asphalt Roll Roofing Materials, Asphalt Roll Roofing Defects, Asphalt Roll

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Roll roofing installation, inspection, troubleshooting, repairs: this article describes mineral-granule coated asphalt roll roofing roofing materials, choices, installations, inspection, defects, roofing repairs, and product sources. Our page top photo shows our client pointing to a low slope area on a roof where mineral-granule coated asphalt roll roofing was applied after shingles in that location had leaked repeatedly. Because mineral-granule-coated modified bitumen roofing can be mistaken for roll roofing, and vice versa, readers should also see MODIFIED BITUMEN ROOFING .

Asphalt Roll Roofing Materials, Choices, Costs, Life Expectancy, Characteristics

Roll roofing is simplest product to install on a small section of lowslope roof is 90-pound roll roofing.

This consists of a heavy, asphalt-saturated organic or fiberglass felt with a granular surface. Rolls are 36 inches wide and weigh 90 pounds. Single-coverage roll roofing typically has a 2-inch lap with exposed nails and is used mainly on utility structures.

Double-coverage roll roofing is installed with a full 19-inch lap joint, leaving a 17-inch exposure, with a 2-inch head-lap.

Nails are concealed under the lap joints that are sealed with asphalt lap cement. With two layers of protection, double-coverage roll roofing is acceptable for small roof areas and can be used on roofs as shallow as 1:12.

In its earliest forms roll roofing consisted of sheets of felt canvas or cloth that were impregnated with asphalt, then rolled flat along a low-slope or even some steeper sloped roofs with the material’s long edge parallel to the building eaves.

Modern 90-pound asphalt roll roofing is built of mineral-coated fiberglass-reinforced mat or organic-mat (bituminous impregnated paper) material very similar to asphalt roof shingles, in 36-inch wide material sold in 36-foot long rolls. Roll roofing is coated on both sides with asphalt and its upper or exposed side is protected with mineral granules.

Common roll roofing material colors are white, brown, black. You may find some roofers referring to roll roofing as 90-pound felt since a 36-foot roll of the material, able to cover about 100 sq.ft. (one roofing square) weighs close to ninety pounds.

Tips For Buying Roll Roofing Materials

Our roll roofing material photo (left) shows that this roll was a bit out of round. When buying roll roofing avoid rolls that are squashed as they may be difficult to roll out smoothly (give the material time to relax and flatten before nailing).

Also avoid rolls whose ends are badly damaged as it may make for uneven or raised seams.

This is an inexpensive roofing material often installed (over 15# felt underlayment) by homeowners and do-it-yourself-ers.

Installing Roll Roofing for Maximum Life

Nonetheless roll roofing installations will have a longer life if installed according to the product manufacturer’s instructions, nailed at proper intervals, and with seams properly sealed.

It’s also important to install roll roofing over a smooth sound roof deck. If the roof decking sags, ponding on the roof surface after rain may reduce its life.

Overlapping strips of asphalt roll roofing are installed over the roof surfaces with overlapped edge joints sealed, usually with a heated asphalt compound, or cold-applied using a similar sealant that functions at lower temperatures.

Probably in part because asphalt roll roofing is typically used on low slope and nearly flat roofs, it can have an anticipated wear life of less than ten years, often five years.

The life of roll roofing may be extended by coatings.

Common Problems on Roll-Roofing Covered Roofs

As Carson Dunlop’s sketch (at left) illustrates,

  • A common roll roofing problem includes wrinkles or bubbles. Granule loss and exposure of bald spots or cracking are common signs that roll roofing is at the end of its life

Not quite so common, but we also see misapplications of roll roofing such as:

    Running the roll roofing over a 90-degree angle and up the vertical surface of a parapet wall or chimney as flashing Running roll roofing with its seams parallel to the building gable ends

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Roll roofing installation, inspection, troubleshooting, repairs: this article describes mineral-granule coated asphalt roll roofing roofing materials, choices, installations, inspection, defects, roofing repairs, and product sources. Our page top photo shows our client pointing to a low slope area on a roof where mineral-granule coated asphalt roll roofing was applied after shingles in that location had leaked repeatedly. Because mineral-granule-coated modified bitumen roofing can be mistaken for roll roofing, and vice versa, readers should also see MODIFIED BITUMEN ROOFING .

Asphalt Roll Roofing Materials, Choices, Costs, Life Expectancy, Characteristics

Roll roofing is simplest product to install on a small section of lowslope roof is 90-pound roll roofing.

Roll Roofing Products, Asphalt Roll Roofing Materials, Asphalt Roll Roofing Defects, Asphalt Roll

This consists of a heavy, asphalt-saturated organic or fiberglass felt with a granular surface. Rolls are 36 inches wide and weigh 90 pounds. Single-coverage roll roofing typically has a 2-inch lap with exposed nails and is used mainly on utility structures.

Double-coverage roll roofing is installed with a full 19-inch lap joint, leaving a 17-inch exposure, with a 2-inch head-lap.

Nails are concealed under the lap joints that are sealed with asphalt lap cement. With two layers of protection, double-coverage roll roofing is acceptable for small roof areas and can be used on roofs as shallow as 1:12.

In its earliest forms roll roofing consisted of sheets of felt canvas or cloth that were impregnated with asphalt, then rolled flat along a low-slope or even some steeper sloped roofs with the material’s long edge parallel to the building eaves.

Modern 90-pound asphalt roll roofing is built of mineral-coated fiberglass-reinforced mat or organic-mat (bituminous impregnated paper) material very similar to asphalt roof shingles, in 36-inch wide material sold in 36-foot long rolls. Roll roofing is coated on both sides with asphalt and its upper or exposed side is protected with mineral granules.

Common roll roofing material colors are white, brown, black. You may find some roofers referring to roll roofing as 90-pound felt since a 36-foot roll of the material, able to cover about 100 sq.ft. (one roofing square) weighs close to ninety pounds.

Tips For Buying Roll Roofing Materials

Our roll roofing material photo (left) shows that this roll was a bit out of round. When buying roll roofing avoid rolls that are squashed as they may be difficult to roll out smoothly (give the material time to relax and flatten before nailing).

Also avoid rolls whose ends are badly damaged as it may make for uneven or raised seams.

This is an inexpensive roofing material often installed (over 15# felt underlayment) by homeowners and do-it-yourself-ers.

Installing Roll Roofing for Maximum Life

Nonetheless roll roofing installations will have a longer life if installed according to the product manufacturer’s instructions, nailed at proper intervals, and with seams properly sealed.

It’s also important to install roll roofing over a smooth sound roof deck. If the roof decking sags, ponding on the roof surface after rain may reduce its life.

Overlapping strips of asphalt roll roofing are installed over the roof surfaces with overlapped edge joints sealed, usually with a heated asphalt compound, or cold-applied using a similar sealant that functions at lower temperatures.

Probably in part because asphalt roll roofing is typically used on low slope and nearly flat roofs, it can have an anticipated wear life of less than ten years, often five years.

The life of roll roofing may be extended by coatings.

Common Problems on Roll-Roofing Covered Roofs

As Carson Dunlop’s sketch (at left) illustrates,

  • A common roll roofing problem includes wrinkles or bubbles. Granule loss and exposure of bald spots or cracking are common signs that roll roofing is at the end of its life

Not quite so common, but we also see misapplications of roll roofing such as:

    Running the roll roofing over a 90-degree angle and up the vertical surface of a parapet wall or chimney as flashing Running roll roofing with its seams parallel to the building gable ends


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