| Date |
Text |
| 2009-11-04 11:13:54 | 2004 FBC W/2007 REVISIONS |
| | |
| | 1)THE REVISION TO CHANGE THE ROOF SHEATHING FASTENING |
| | ON SHEET S-2 TO 6D RING SHANK NAILS OR 8D COMMON NAILS |
| | DOES NOT COMPLY WITH THE MINIMUM REQUIREMENTS OF THE |
| | FBC RESIDENTIAL. SECTION R803.2.3.1 WHICH REQUIRES 8D |
| | RING SHANK NAILS. EXCEPTION #3 ALLOWS 8D COMMON WHERE |
| | DESIGN WIND-SPEEDS ARE 100 MPH OR LESS, HOWEVER, THIS |
| | PROJECT REQUIRES A DESIGN WIND-SPEED OF 140 MPH. |
| | THEREFORE, 8D RING SHANK NAILS ARE REQUIRED. ALSO SEE |
| | BOAF INFORMAL INTERPRETATION REPORT NUMBERS 5600 AND |
| | 5954 AT THE LINKS PROVIDED BELOW. |
| | HTTP://WWW.BOAF.NET/PDF/I-LIST/5600.PDF AND |
| | HTTP://WWW.BOAF.NET/PDF/I-LIST/5954.PDF |
| | NOTE: IN THE PROPOSED MODIFICATION TO THE FLORIDA |
| | BUILDING CODE RESIDENTIAL SECTION R803.2.3, THAT WAS |
| | ADOPTED INTO THE CODE, TEST RESULTS FROM CLEMSON |
| | UNIVERSITY (REINHOLD 2000 - 2002, MCKINLEY 2001) AND AT |
| | THE INTERNATIONAL HURRICANE CENTER - FLORIDA |
| | INTERNATIONAL UNIVERSITY (REINHOLD, ALVAREZ 2003) |
| | COMPARED MEAN FAILURE PRESSURE IN PSF FOR 5/8 INCH |
| | THICK PLYWOOD ROOF SHEATHING PANELS USING BOTH 8D |
| | COMMON AND 8D RING SHANK NAILS SPACED AT 6 INCHES AND |
| | ATTACHED TO 2 X 4 SOUTHERN YELLOW PINE RAFTERS WERE |
| | REFERENCED. THE TESTS SHOWED A MEAN ULTIMATE UPLIFT |
| | CAPACITY OF 126 PSF FOR PANELS ATTACHED WITH 8D COMMONS |
| | AND 292 PSF FOR THOSE ATTACHED WITH 8D RING SHANK. |
| | USING THIS TEST DATA AND A DESIGN PROCEDURE (REINHOLD |
| | 2002) CALCULATED THE DESIGN UPLIFT PRESSURE FOR 19/32 |
| | THICK PLYWOOD ROOF SHEATHING TO BE 58 PSF FOR THE 8D |
| | COMMON NAILS AND 150 PSF FOR 8D RING SHANK NAILS. THESE |
| | RESULTS SHOWED THAT THE 8D COMMON NAILS WOULD ONLY MEET |
| | ALLOWABLE DESIGN UPLIFT PRESSURES FOR SOME LIMITED ROOF |
| | CONDITIONS, ROOF HEIGHTS AND ONLY UP TO WIND SPEEDS OF |
| | 120 MPH. |
| | |
| | 2) THE REVISION TO DETAIL C/S3 ON SHEET S3 REMOVING THE |
| | FIRE RETARDANT FROM THE UNDERSIDE OF THE ROOF SHEATHING |
| | THAT IS REQUIRED BY FBC R317.2.2 DOES NOT COMPLY WITH |
| | CODE. ALL PORTIONS OF THE TWO ROOFS SEPARATED BY THE |
| | COMMON WALL WHERE THE HIGHER ROOF IS LESS THAN 18 |
| | INCHES ABOVE THE LOWER ROOF ARE REQUIRED TO HAVE THE |
| | FIRE RETARDANT FOR A DISTANCE OF FOUR FEET ON EACH SIDE |
| | OF THE WALL AS REQUIRED BY FBC R317.2.2. |
| | |
| | ROBERT MCDOUGAL |
| | BLDG. PLAN REVIEW |
| | (561)805-6714 |
| | [email protected] |
