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48 exposed ground in crawl spaces or unexcavated area located within the <br /> 49 periphery of the building foundation. <br /> 50 2. All wood framing members that rest on concrete or masonry exterior <br /> si foundation walls and are less than 8 inches (203 mm) from the exposed <br /> 52 ground. <br /> 53 <br /> 54 <br /> 55 The standard used across much of the nation has proven for well over 30 years to be a <br /> 56 performance code standard that has worked without issue in single family dwellings. <br /> 57 <br /> 58 Wood construction maintained at a moisture content of 19-20 percent or less will not <br /> 59 decay. Optimum conditions for decay occur when moisture content is above 25%. It <br /> 60 should be noted that when wood is elevated and properly protected from water or from <br /> 61 vapor condensation, and exposed to normal atmospheric conditions such as exist inside <br /> 62 buildings and outdoors, it's moisture content rarely exceeds even 15%therefor moisture <br /> 63 content control by means of accepted design and construction details can be a simple <br /> 64 and practical method of providing <br /> 65 Protection against decay. <br /> 66 <br /> 67 In the case of this foundation and the sill plates that were likely installed over 25-30 <br /> 68 years ago based on site materials and evidence from listings etc. The Dwelling sill <br /> 69 plates in question have no signs of water staining, dry rot or repairs or conditions in the <br /> 70 underfloor which are signs of moisture intrusion which cause dry rot . Section R-309.1 <br /> I71 allowed this exception with an 8" clearance in the Oregon One and Two Family Dwelling <br /> r.72 Code even in 1993 up to the latest errata of 4/20/1993. <br /> 73 <br /> 74 There is clear evidence in the model code used across the nation that this alternate <br /> 75 method to the current 2011 ORSC is an equal alternate method that from a <br /> 76 performance standard on site at this dwelling and across the nation has worked without <br /> 77 failure of the sill plate. <br /> 78 <br /> 79 My Building Code consultant I have hired has seen this type of untreated Douglas Fir sill <br /> 80 plate in very harsh environments (compared to Marion County) last well over 175 years <br /> si in Oregon's oldest coastal cities without problems. This is a performance example of <br /> 82 how this method also has worked well in Oregon in one of the most severe dry rot prone <br /> 83 regions of the West Coast. During his inspection the lumber was tested and found to <br /> 84 have moisture content less than 19% and no past water staining on termite tuber signs <br /> 85 or damage. My consultant is also a licensed Oregon Certified Home Inspector who <br /> 86 regularly performs pest and dry rot inspections. <br /> 87 <br /> 88 The standard 8"minimum separation is also listed in the current: "AF&PA Wood Frame <br /> 89 Design of Structures for Permanence". This book; a nationally recognized standard for <br /> 90 Wood Frame Construction Permanence, is used by design professionals across the <br /> 91 nation. <br /> 92 <br /> 93 The American Forest and Paper Association (AF&PA) Wood Frame Construction <br /> 94 Manual for One- and Two-Family Dwellings (WFCM) is an alternate framing method <br /> �.5 allowed by the current ORSC section R301.2.1.1 Design Criteria. In the 2012 AF&PA <br /> 2 <br />