Laserfiche WebLink
_ , OPTIONAL DESIGN METHOU <br /> � A's an opt�on to comPleting the Exterior Envolope Average "U" Com�utation where <br /> "U" values have to be calculated, the following method may be used. <br /> NOTE: Al1 of the following six items must be accomplished in order to <br /> utilize this method. <br /> . �> 1 . Ceilings which meet one of the following criteria satisfy this requirement: <br /> A. R-38 throughout the entire ceiling. Indicate on plan section drawing how <br /> this will be accomplished. Complete appropriate diagram F, G, or H. <br /> B.� If a portion of the ceiling is less than R-38, the insulation in the <br /> remainder of the ceiling must be increased to yield an overall average <br /> thermal resistance of not less than R-38. <br /> C. Where the roof at the perimeter of the ceiling prevents installation of <br /> insulation to full depth, the insulation in the remainder of the ceilino <br /> must be increased to reduce the overall ceiling heat loss to no more y <br /> than if R-38 had been installed throughout the entire ceiling. <br /> (Submit calculations if this method is used) . <br /> �i 2. For the insulated cavity of opaque wall and rim joists, but not foundation <br /> walls, a minimum R-20 is required. Complete diagrams 6 and C. <br /> ""'� 3. For the insulated cavity of floors of heated spaces over unheated spaces, <br /> a minimum of R-20 is required. <br /> �-► 4. Maximum glass area may not exceed 12% of the area of exterior walls not <br /> including foundation walls. All windows shall be double glazed or have <br /> storm windows. Complete the following equation using data from the <br /> first page: <br /> 3(a) = 3(t) _ <br /> x <br /> 7G SF- . G �D = ��� wN� S <br /> (X c�K <br /> (x) must be less than .12 to meet requirem ents of this item. <br /> �—> 5. Maximum glass area may not exceed 10% of the area of exterior walls, not <br /> including foundation walls, when a sliding glass door is installed. All <br /> glass shall be double glazed or have storm windows. If sliding glass <br /> doors are to be installed, complete the following equation using data from <br /> the first page: <br /> [(a) + 3(c� : 3(t) _ <br /> Y <br /> . , _ <br /> Y <br /> (y) must be less than .10 to meet requiranents of this item. <br /> �� 6. A 1 3/4" metal faced door system with an insulated core providing an R value <br /> equal to or greater than 3.0 or a conventional door and storm. All primary <br /> doors must have durable weatherstripping. <br /> . Page 6 <br />