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2014, 01-09 Permit BLD-2013-2590 Engineer LtrAdams & Clark, Inc. 1720 W. Fourth Ave. • Spokane, WA 99201 • (509) 747-4600 • Fax (509) 747-8913 • www.adamsandclark.com January 9, 2014 Mike Eberle 13610 E. 28`h Avenue Spokane, WA 99216 '&0- DUI RE: Patio Cover — 10911/10913 E. Broadway Avenue Mike: I visited the above referenced site at your request in regards to the construction of a 18'-0" x 40'-6" porch roof and the option of installing exterior walls and offer the following: The roof covered area is broken in to 2 sections. The roof was constructed with 2" x 6" roof trusses spaced at 24" O.C. and span 16'. The trusses are supported by truss hangers with a ledger board con- nected to the existing house and 2 — 2"x6" members acting as a wood beam separated by the 6" columns. The open span of the roof trusses is 14'-3" and the column spacing is 9'-0". The columns are constructed using 2 — 2"x6" members with a 2"x6" spacer. Analysis: After reviewing the structure after placement of exterior walls, the only affected load to the structure would be wind load. This load was not sufficient to cause any lateral displacement of the structure. How- ever, during our review, it was determined the 2"x6" roof trusses at 24" O.C. are not adequate to support a 10 psf dead load and a 40 psf snow load. In addition, the 2 — 2"x6" beams are not adequate to support the dead/snow load from the roof. Recommendations: Based on the above review, the following construction recommendations are as follows: 1. Install a beam, minimum 4"x6", placed at the midspan of the roof rafters. The beam shall be supported by the existing interior wall and a 4"x6" wood column installed at the exterior. As an alternative to installing an additional support beam, 2"x8" roof rafters installed between each existing roof rafter and run full span from house ledger to wood beam. 2. Existing wood beam between columns will require an additional 2"x6" member be installed. This member can be constructed on either side of the beam and run the full length of the existing members. 3. 2"x6" blocking must be installed in the open space of the column at the mid height point. The blocking must be a minimum of 3'-0" in length and centered at the midpoint.. After reviewing the proposed project, the above referenced construction methods for tall wall construction, meet or exceed the standard building industry requirements for structural stability per the 2012 International Residential Code (IRC) and the 2012 International Building Code (IBC). Sincerely, Adams & Clark, Inc. Greg S.(Nliller, P.E. Project Engineer Civil Engineers • Land Surveyors Land Planners • Landscape Architects Adams & Clark, Inc. 1720 W. Fourth Ave. Spokane, WA 99201-5302 9920 - r3 A. . WA 990 n Jenny Nickerson City of Spokane Valley 11703 E. Sprague Ave. Suite 6-3 Spokane Valley, WA 99206