Roofing/Roof Repair


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Hello Bruce.. recently completed a roof repair on a low slope porch roof that ens on top of a double wide.  I added new asphalt shingles to a 10x10 section of the lower right corner of the porch roof and ended up with two seams.  I've ended up with a slight gap where the old and new roof meet along the top of the repair the other along the right hand side.  The existing shingles are stapled to the roof and old and brittle.  I'm looking for suggestions and ideas to end up with a waterproof seam between the new and old shingles.  I'm using roofing cement and fabric over the seams as a temporary fix, but don't expect this will be 100% water proof.  I have thought of attempting to put flashing under the older shingles and over the new shingles.  Anyway, any advice/ideas are appreciated.  Thanks, Frank


The fasteners in the last underlying course of existing shingles must be removed at the high side of your repair interface and the existing shingles on the side left side of your tie in have to be removed to the nearest butt joint, removing fasteners from overlying shingles as required to remove lower ones.  This area should look a little 'toothed' when you are done with the prep.

Install your new underlayment to tuck under the existing by 4" on the high side and on the left 12" if you can get it.  Your underlayment starts at the bottom.

Start your shingles at the bottom and butt a full shingle to the existing and match the shingle exposure of the existing.  New shingles at the upper courses of your repair area should tuck under and have the appropriate butt joint offsets if you have stayed true to the original pattern of the existing roof.  Don't forget to renail the first two courses of existing shingles at the high side of your repair once the last course of new shingles is tucked under everything!


Bruce Ryan II, RRO
Professional Roof Consultants, Inc.


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Bruce A. Ryan II, RRO


I offer solid knowlege of all types of Commercial and Residential Roofing, Waterproofing, and, Building Envelope systems. Experience ranges across low slope and steep slope roof systems. I am also well versed in matters regarding condensation and ventilation. I enjoy donating some of my time and knowledge to the betterment of others.


Bruce Ryan has 20 years of roofing, waterproofing, and building envelope consulting experience with PRC, with 5 years of commercial roofing experience prior to joining the firm. He became Vice President of the company in 1998. Bruce Ryan plays a key role in the development of practical, long-term roofing and waterproofing solutions, along with implementation of on-site forensic studies. Bruce also has a high level of experience with regard to the impacts of roofing materials and construction for demanding clients with heavily occupied structures.

Oregon Construction Contractors Board Construction Specifiers Institute National Roofing Contractors Association The Institute of Roofing, Waterproofing, & Building Envelope Professionals Oregon Board of Investigators Installation Masters

University of Maryland BS Business & Administration Registered Roof Observer - RCI Private Investigator Certified EIFS inspector - Northwest Wall and Ceiling Bureau Certified InstallationMaster™ - The Installation Masters™ Training and Certification Program (developed by American Architectural Manufacturers Association)

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