Wiktionary
n. (alternative spelling of tarpaper English)
WordNet
n. a heavy paper impregnated with tar and used as part of a roof for waterproofing [syn: roofing paper]
Wikipedia
Tar paper is a heavy-duty paper used in construction. Tar paper is made by impregnating paper or fiberglass mat with tar, producing a waterproof material useful for roof construction. Tar paper is distinguished from roofing felt which is impregnated with asphalt instead of tar, but these two products are used the same way, and sometimes are informally used as synonyms.
Tar paper has been in use for centuries. Originally felt was made from recycled rags but today felts are made of recycled paper products (typically cardboard) and sawdust. The most common product is the so-called #15 felt. Before the oil crisis felt weighed about 15 pounds per square (one square = 100 square feet) and hence the asphalt-impregnated felt was called "15#" or "15 pound felt". Modern, inorganic mats no longer weigh 0.73 kg/m2, and to reflect this fact the new felts are called "#15". In fact, #15 mats can weigh from 7.5 to 12.5 pounds/sq depending on the manufacturer and the standard to which felt is made (i.e., CGSB, ASTM D227 Standard Specification for Coal-tar saturated Organic Felt Used in Roofing and Waterproofing, ASTM D4990, Standard Specification for Coal Tar Glass Felt Used in Roofing and Waterproofing, or none). Thirty pound felt, of 30# felt, is now #30 felt, and actually usually weighs between 16 and 27 pounds per square.
Tar paper is more accurately a Grade D building paper (the Grade D designation derives from a US federal specification) which is widely used in the west. Building paper is manufactured from virgin kraft paper, unlike felts, and then impregnated with asphalt. The longer fibres in the kraft paper allow for a lighter weight product with similar and often better mechanical properties than felt. Grade papers are rated in minutes—the amount of time it takes for a moisture sensitive chemical indicator to change colour when a small boat-like sample is floated on water. Common grades include 10, 20, 30, and 60 minute. The higher the rating the more moisture resistant and the heavier. A typical 20 minute paper will weigh about 3.3 lbs per square, a 30-minute paper 3.75, and a 60-minute paper about six. The smaller volume of material however does tend to make these papers less resistant to moisture than heavier felts.
Usage examples of "tar paper".
It is like a mock-up slapped together from tar paper and canvas, like the fake towns where they practiced house-to-house warfare during boot camp.
He's been manufacturing asphalt and tar paper as a cover for making toxaphene.
Its interior was dimly lit with candles and the windows were sealed with tar paper to prevent any light from spilling outside.
Longbeds overloaded with lumber, sheet glass and tar paper streamed south in ragged convoys to the hurricane zone.
The roof was primarily tin and the rest was tar paper and the water ran off it in great gushes.
He had walked into a poor neighborhood on the fringe of the town, into a collection of dilapidated homes patched with tar paper and oilcloth, their painted wooden sides peeling, their shingled roofs cracked and blistered, their yards rutted and littered with ruined toys, discarded appliances, and rusting vehicles.
It wasn't luxurious, but it was a far cry from the peeling tar paper on the neighboring buildings' roofs.
She stepped outside, then walked carefully along the rotting tar paper and gravel, testing each square in front of her.