15# felt is about .030 and 30# felt is about .062..
Forty-pound roofing felt, also known as #40 felt, typically has a thickness of about 0.30 to 0.35 inches. This thickness can vary slightly based on the manufacturer and specific product, but it is generally designed to provide a durable underlayment for roofing applications. It is heavier and thicker than the more common 15-pound and 30-pound felt options.
type I is 15# felt and type II is 30# felt
Here's what I can help you with: 3 roofing squares means 300 square feet (1 square = 100 feet). On a regular basis, one square is covered by 3 bundles of shingles. Roofing felt (1F) is usually supplied in rolls (30 ' of length), with one side covered with sand or synthetic granules. Be aware that there are two kind of felt impregnations: bituminous and tar - there is a distinction between these two. If I were you, I would surely look (and go) for the newest waterproofing membranes, lot more less prone to puncture and tear. I hope this helped. Succes!
the best reason i can think of is the 30lb felt is denser and when applied over and uneven, older pine roof boards or plywood the density would be able to cover blemishes in the sub roof. Splinters from old nail removal, or other slight imperfections. Ice guard as used in freeze areas is also more durable to puncture...The need to lay the 30lb felt with little or no wrinkles also makes for smooth runoff. the use of correct material is important when the pitch of the roof is reduced hope this helps. jerome
Without seeing the plans I can't tell you. I can tell you how to calculate the price of the felt (it hasn't been made out of paper in a very long time--they call it "asphalt impregnated felt" or "roofing felt" now), though. Calculate the square footage of the roof, and divide by either 200 (if you're laying 30-pound felt) or 400 (if you're laying 15-pound felt, which is only really good if you're using three-tab shingles). Calculate the square footage of all the hardwood flooring you're using and divide by 400 (here you ALWAYS use 15-pound felt as 30-pound gives you no advantage) And if you are using felt on the walls under the siding, which means you're too cheap to use something proper like Tyvek, divide the square footage of the walls by 400. Each calculation gave you the number of rolls needed for each area. Add one more roll because you'll almost certainly need it, and multiply the number by the price of felt per roll in your area. 15-pound and 30-pound felt are the same price per roll almost everywhere--if a roll of 15-pound is $16.50, so will a roll of 30-pound be.
30 pound roof felt before your finish material.
That depends. If this is a shingle or "steep slope" roof system, one layer of felt lapped 4" would be sufficient. A typical roll of #30 felt covers 200 sf.
it depends on the shingles, regelar 3 tab shingles use 15 lb felt, archatectual requires 30 lb felt and sheet metal requires 30 lb felt. but always check on the shingle package and your local building codes for specs
When talking roofing materials. A square is considered a 10'x10' area or a 100 square feet. So you have 1,900 square feet. There are two basic types of felt: 15lb and 30lb felt. 15lb felt covers 4 sq= Total needed will be 5 rolls 30lb felt covers 2 sq= Total needed will be 10 rolls (*note, 30lb is more thick and better for your roof.
60 minute building paper is used to build..
30 pounds, lb means pounds
30# felt is thicker..... Better?