Ch.23 Measurement and drafting Flashcards
Part of a dimension string that is not given a dimension value on the drawings
Open dimension
Process of measuring that uses a laser based instrument with an onboard computer to measure the distance, horizontal, and vertical angles of the instruments LazarBeam to a reflective prism target. This instrument is accurate to 1/64 inch at 1600 feet.
Electronic distance measurement EDM
This type of device does not require the use of a prism reflector; instead, it relies on the return signal bounced from the object is being measured. The accuracy is West precise at 1/8 inch at 100 feet. This is affected by the obliqueness of the laserbeam on the targeted point, the distance from the instrument to the target point, and the reflective quality of texture of the targeted point
Reflector less electronic distance measurement REDM
Use the large format, film based view camera to photograph the sides. The cameras focal plane is it parallel to the Poseidon gives a flat image with no perspective distortion. Dimensions can be scared off of the image, but to improve accuracy, the building plane should be relatively flat. In addition to providing the ability to scale building elements not readily accessible to hand measuring, the photograph provides an accurate image of the building as a photograph would
Rectified photography
Similar to rectified photography except that it relies on digital photography in correction of optical distortion through computer software
Ortho photography
Is the serving of objects or Spaces by using photography and an associated software
Photogrammetry
Uses to overlapping photographs that are loaded into a computer program to produce a digital stereo image. The image can then be used to extract information to make a three dimensional drawing. In addition to producing accurate three dimensional drawings, this technique also produces a photographic record. It does require specialized equipment in computer software, as well as train technicians to do the work
Stereo photogrammetry
Uses multiple, oblique photographic images of an object taken at different angles. Measurements and three-dimensional models are derived by using soft field measurements technique required that reference points be established by standard survey techniques or by measuring distances between the reference points to establish it correctly skilled coordinate system that the software can use. Although relatively inexpensive, it is slower than laser skating. It has an accuracy of about 0.05%
Convergent photogrammetry
Uses medium range, posing laser beams, which the magically sleep over an object or space to obtain three-dimensional coordinates of points on the surface of the object or space being scanned. The resulting image is a point cloud forming of three-dimensional image. From this image, plants, elevations, sections, and three dimensional models are developed by software. The laser scans from one or more points, depending on the exact system being used. For multiple rooms interiors, the image can be stitched together to give an overall image of the entire building. Unlike photogrammetry, no surveyed reference points are required; all the information can be gathered from a single point rather than from multiple photographs. Laser scanning has an accuracy ranging from 0.05% to 0.01% or better
Laser scanning
The actual occupant area required by a client to accommodate specific functions
Net area
The amount of space needed for passage
Circulations space
Includes areas that are not occupied by the tenant, such as closets, structural columns, and walls. However, these areas will still need to be taken into consideration when determining space needs
Incidental space
The mathematical ratio of one area to another. Interior layout efficiency factors take into account the required circulation space needed per tenant, as well as the non-usable space required for partitions, columns, and so on.
Efficiency factor
The area the total portion of the building being actively used by the tenant
Occupant area
Calculated by dividing the net area by the efficiency factor. Alternatively, the required in that area can be increased by multiplying by the inverse of the efficiency factor to arrive at an approximate occupant area.
Estimated required occupant area
The product of the tenants occupant area in the load factor to account for this shared portions of the building
Rentable area
The minimum path on a multi argument for necessary for access to and egress from occupant areas, elevators, stairs, restrooms, janitors closet, and similar areas
Base Building circulation
Method to determine the rentable area of a tenant may result in different load factors for each floor of a multi floor building, and uses a separate R/U ratio for each floor.
The legacy method
