Roof Flashing Over Shingles

How to roof over existing shingles.

Roof flashing over shingles.

Step flashing protects the joints between the roof deck and chimneys or dormers. Vent pipe flashing fits over flues or pipes. Before you reshingle a roof read our step by step guide for adding new shingles over old ones. While some skylight manufacturers include flashing in their products sometimes roofing professionals have to create it or purchase it separately.

Kshepard kenton shepard cmi june 17 2009 3 35pm. Step flashing built to protect joints between roofs chimneys and other objects like skylights this flashing steps up above the shingles and attaches to the object providing comprehensive water protection. Flashing and additional rows of shingles. Beveled wood pieces called horsefeathers must be laid along the thick edges of the shakes to make a fairly flat surface.

Installation is easier than for a tear off job because you can use the existing shingles as guides for laying the new ones. Vent pipe flashing as the name implies this flashing is usually. Flashing must be installed correctly around elements such as vents or chimneys that penetrate the roof as well as in valleys where different parts of. Flashing can be purchased in pre formed styles to help you install it more easily and these include.

Asphalt shingles can be laid over cedar shakes or shingles however this is a roofing project best left to pros. There is a valley on the roof right to the left of the garage you can t see it in the picture but it too had flashing put on top of the shingles. The edge of the roof has thin metal flashing that helps water drip off the roof without damaging the home or causing a leak. I usually see this with shingls up to the tube tube flasnhing installed over the lower shingles and then the top half covered with shingles.

Open valleys have metal flashing to protect this critical area of the roof. Step flashing fits to each course of shingles and appears to step up the wall of the chimney. The flashing shall be a minimum of 4 inches 102 mm high and 4 inches 102 mm wide. At the end of the vertical sidewall the step flashing shall be turned out in a manner that directs water away from the wall and onto the roof and or gutter.

Although it sounds like a good idea we can assure you the cons heavily outweigh the pros. When contemplating a new roof many people hope to simply do a shingle over and avoid the extra cost and mess of tearing off the existing roof and starting from scratch. If conditions are right new shingles laid over old shingles can be just as attractive and durable as shingles laid on bare sheathing.