Here we see how one would strip a roof of its old shingles in order to prepare it for new shingles.   This house was built around 1955. There were two layers of shingles on the roof. The low-pitched roof measured about 14' x 42' on each plane, or just under 1200 square feet. The roof is a simple gable design with no valleys.     Here we see an asphalt roof that is about to be removed and replaced. It is possible to apply a second layer directly over the existing shingles, but this does add a tremendous dead load to the roof structure. The old roof had one leak, which was near the chimney, and many curled and broken shingles. Although the leak could have been repaired, and the roof left alone for a few more years, the homeowner chose to re shingle it while the time and money was available.     This tool is a shingle scraper. It is basically a flat-blade shovel with some big teeth. There is a triangular "heel" welded to the bottom, which acts like a ramp to pivot the scraper against and lift the shingles from the roof.     A square mouth shovel and a garden fork work just as well, and you probably own these already. This flat-blade garden shovel also works modestly well for removing shingles. This garden pitch fork worked quite well for removing just the top layer of shingles, making it much easier to carry them to the edge of the roof for disposal.     The scraper is simply pushed under the shingles and lifted. This tool does a decent job of prying up the roofing nails as well.     Disposal Of Shingles: One of the biggest drawbacks to re-shingling a roof is disposing of the old shingles. Anyone who has never done shingling work before might be surprised at the weight of asphalt shingles. Even the cheapest grades of shingles weigh around 225 pounds per square (in the roofing and siding business, a "square" is 100 square feet). This roof had 2 layers of roofing, and about 12 squares of roof area, so all the old shingles should weigh about 5400 pounds. That's almost 3 tons! The owner of this house had another project nearby that required a huge dumpster, so we simply dropped the waste shingles into two utility trailers parked below, and hauled the debris to the dumpster.     It takes about an hour to scrape the shingles from one side, with 4 people working. There may still be a lot of tiny pieces of shingle stuck to the wood, and many roofing nails that will need to be removed or pounded down.     The plumbing vent stack in this case had an old metal flashing around it, and it was sealed with gobs of roofing tar. The flashing was removed and the tar scraped away.     This is a typical scrap of shingle that was left behind by the shovels and scrapers.     A rip-claw hammer was used to yank out the nails. Any remaining debris should be removed by hand, and remaining nails should be pulled out, or hammered down. This process takes about 30 minutes per side.     There were many boards with loose nails. This roof was sheathed with 1x10 planks, as was common before the widespread use of plywood for roof and floor sheathing. These were all hammered down.   Graphics and text used with permission, Hammerzone.com .