Closure Checking

A traverse closure is performed on the boundary and all of the individual lots (or units).  Closures are computed using the bearings and distances shown on the final mylars only.  Copies of closures submitted by the surveyor are not used.  An independent check is more likely to spot a problem than searching closure sheets for transpositions, etc.  The closure must meet the legal minimum requirements of the current rules and regulations.  Closure tolerance is 1:10,000*

Review

·            A traverse closure for the boundary is calculated by starting at the Real Point of Beginning of the subdivision and proceeding in a clockwise direction using bearings and distances from the plat mylars.  Curves are entered using the Delta / Radius / Chord Bearing information from the curve tables.    The chord bearing is entered exactly as shown in the curve table.

·            A traverse closure for each lot (or unit) is calculated by starting at the southwest corner of the lot (or unit) and proceeding in a clockwise direction using bearings and distances from the plat mylars.  Occasionally, determining the southwest corner of the lot is a little vague. Rock, scissor, and paper often solves this dilemma.

·            Can the direction of the arc be determined?    This is occasionally difficult where a very large radius, short chord curve is involved.  If the direction cannot be determined from opposing curves, it may be suggested that a label or some other way of identifying the curve arc be added.  This could also be critical if a lot area is so close to the minimum requirement that an error in arc direction could affect the area.

·            The calls for the boundary traverse in the Certificate of Owners are checked against the face of the plat.  If the call in the Certificate of Owners calls for N89°00’00”E, and on the face of the plat is labeled S89°00’00”W, a comment is made about reversing the direction to match the Certificate of Owners.  The same criteria are applied to boundary bearings shown in the line and curve tables.

References:  I.C. 50-1303, I.C. 55-1911 , *Ada County Code 8-6-4-3(B) and the Minimum Standards for Land Boundary Surveys, Land Descriptions and Maps, by the Idaho Society of Professional Land Surveyors (Adopted March 21, 1992).

Last revised: 04/27/2010

Closure Checking

A traverse closure is performed on the boundary and all of the individual lots (or units).  Closures are computed using the bearings and distances shown on the final mylars only.  Copies of closures submitted by the surveyor are not used.  An independent check is more likely to spot a problem than searching closure sheets for transpositions, etc.  The closure must meet the legal minimum requirements of the current rules and regulations.  Closure tolerance is 1:10,000*

Review

·            A traverse closure for the boundary is calculated by starting at the Real Point of Beginning of the subdivision and proceeding in a clockwise direction using bearings and distances from the plat mylars.  Curves are entered using the Delta / Radius / Chord Bearing information from the curve tables.    The chord bearing is entered exactly as shown in the curve table.

·            A traverse closure for each lot (or unit) is calculated by starting at the southwest corner of the lot (or unit) and proceeding in a clockwise direction using bearings and distances from the plat mylars.  Occasionally, determining the southwest corner of the lot is a little vague. Rock, scissor, and paper often solves this dilemma.

·            Can the direction of the arc be determined?    This is occasionally difficult where a very large radius, short chord curve is involved.  If the direction cannot be determined from opposing curves, it may be suggested that a label or some other way of identifying the curve arc be added.  This could also be critical if a lot area is so close to the minimum requirement that an error in arc direction could affect the area.

·            The calls for the boundary traverse in the Certificate of Owners are checked against the face of the plat.  If the call in the Certificate of Owners calls for N89°00’00”E, and on the face of the plat is labeled S89°00’00”W, a comment is made about reversing the direction to match the Certificate of Owners.  The same criteria are applied to boundary bearings shown in the line and curve tables.

References:  I.C. 50-1303, I.C. 55-1911 , *Ada County Code 8-6-4-3(B) and the Minimum Standards for Land Boundary Surveys, Land Descriptions and Maps, by the Idaho Society of Professional Land Surveyors (Adopted March 21, 1992).

Last revised: 04/27/2010