APPENDIX V
MISCELLANEOUS ESTIMATING
Excavations. Excavations are estimated in terms of the cubic yard, 27 cubic feet. The price per yard will vary according to the nature of the soil.
Where ground is not level, the plot should be divided into squares, each square being figured as to its cubical contents and the various amounts combined.
ANALYSIS OF COST FACTORS PER CUBIC YARD
Concrete.—Concrete is estimated in terms of the cubic yard. The price will vary somewhat according to the mixture and the amount of form work required. Mixtures are designated as "rich"—1 part cement, 2 parts sand, 4 parts crushed rock, by volume; "medium"—1:2½:5; "ordinary"—1:3:6, and "lean,"—1:4:8. The rich mixture is used for cellar floors on high grade work. Cisterns and tanks make use of a special mixture of 1:2:3, the stone or gravel being passed thru a %" screen. Cement topping for cellar floors is a mortar composed of 1 part cement and 2 parts sharp sand. Sometimes a 1:1 mixture is used. Cellar floors and sidewalks are often priced by the foot surface measure, standard specifications for depth and construction being understood.
TABLE FOR ESTIMATING QUANTITIES FOR CONCRETE
(Proportion of materials in one cubic foot of concrete.)
ExampleEstimate quantities of various materials neededfor a wall 10" × 7' × 48', using a 1:2½:5 mixture.Solution—(10 × 7 × 48) / 12 = 280 cu. ft.Cement = 280 × 0.048 bbl. = 13.44 bbl.Sand = 280 × 0. 017 cu. yd. = 4.76 cu. yd.Stone = 280 × 0.0341 cu. yd. = 9.548 cu. yd.
Knowing the cost of cement per bbl. and of sand and stone per cu. yd., the cost of materials for the wall may be easily determined.
TABLE FOR ESTIMATING QUANTITIES FOR CEMENT MORTAR
(Proportion of materials in one cubic foot of cement mortar)
ExampleEstimate quantities of material for 1:2 cementmortar for topping of cellar floor 1" × 24' × 40'.Solution—(24 × 40) = 80 cu. ft.Cement = 80 × 0.1239 bbl. = 9.912 bbl.Sand = 80 × 0.0344 cu. yd. = 2. 752 cu. yd.
ANALYSIS OF LABOR COST FACTORS PER CUBIC YARD
Cellar floor construction costs approximately the same as wall work having forms. The expense of form work in ordinary basementwall construction is offset by labor and additional cement cost of topping of cellar floor.
Brickwork.—The unit of measurement in brickwork is the 1000 bricks, ordinarily.
To determine the number of bricks in a wall, multiply each square foot of surface by 7 (sometimes 7½ is used) which is the average number of bricks per foot of wall when 4" thick. Add 5% for breakage. Deduct for openings over 2' square. For walls thicker than 4", make suitable allowance.
A mason can lay 800 to 1000 common and 300 to 400 face bricks in a day.
Bricks may be laid in lime mortar or in cement mortar.
ANALYSIS OF COST FACTORS PER 1000 BRICKS, LIME MORTAR 1:3
ANALYSIS OF COST FACTORS PER 1000 BRICKS, CEMENT MORTAR 1:3
Chimneys.—One foot of chimney height will contain five courses of ordinary bricks.
CHIMNEYS
Slate Roof.—Exposure of each slate will equal the length of a slate diminished by 3" (the usual amount of lap) divided by 2, multiplied by the width of the slate.
To determine the number of slates required, divide the area to be covered by the exposure of each slate as determined just above.
Example—Determine the number of 6" × 12" slates required tocover a surface 16' × 20'.Solution—( (12" - 3") / 2) × 6" = 27 sq. in.(16 × 20 × 144") / 27" = 1707 slates.
TABLE OF SLATES PER SQUARE OF 100 FEET
ANALYSIS OF COST FACTORS PER SQUARE. (100 SQ. FT.)
Plastering.—Plastering is estimated by the square yard. In estimating the number of square yards, deduct ½ the area of openings. The extra labor involved in working around grounds is thus allowed for. Strips of plastering less than 1 foot wide are estimated as a foot in width. Closet areas are increased by J/ to make allowance for the extra labor involved in working small surfaces. Special plastering of cornice, etc., will be charged extra:Lathing is usually a part of the plasterer's contract, tho done by a different set of workmen. The unit is either the square yard or the 1000 laths.
ANALYSIS OF COST FACTORS FOR LATHING A SQUARE (100 SQ. FT.)
ANALYSIS OF COST FACTORS PER SQUARE FOR 2-COAT LIME PLASTER
ANALYSIS OF COST FACTORS PER SQUARE FOR 3-COAT LIME PLASTER
Painting.—Painting is estimated by the square yard, no deductions being made for openings such as doors and windows. Railings, grills, etc., are figured as if solid.
A gallon of paint will cover approximately 250 to 300 sq. ft. of old work and 350 ft. of new work. A painter should cover 150 sq. ft, 1st. coat, per hour, and 90 sq. ft., 2nd coat.
Cost factors may be easily determined from the above statements, and costs easily estimated for ordinary work.
Chicago Millwork Supply Co.:Price Book and Specifications for Lumber and Millwork, Chicago.Gillette:Handbook of Cost Data, Myron C. Clark Co., New York.Gordon-Van Tine Co.:Price Book and Specifications for Lumber and Millwork, Davenport, Iowa.Griffith:Essentials of Woodworking, Manual Arts Press, Peoria, Ill.Hodgson:Modern Carpentry, Frederick J. Drake Co., Chicago.Hodgson:Practical Uses of the Steel Square, Frederick J. Drake Co-., Chicago.Kidder:Architects' and Builders' Pocket Book, John Wiley and Sons, New York.Kidder:Building, Construction and Superintendence, Wm. T. Comstock, New York.Radford:Cyclopedia of Building Construction, Radford Architectural Co., Chicago.Radford:Details of Building Construction, Radford Architectural Co., Chicago.The National Hardwood Lumber Association:Rules for Measurement and Inspection of Hardwood Lumber, McCormick Bldg., Chicago.
Chicago Millwork Supply Co.:Price Book and Specifications for Lumber and Millwork, Chicago.
Gillette:Handbook of Cost Data, Myron C. Clark Co., New York.
Gordon-Van Tine Co.:Price Book and Specifications for Lumber and Millwork, Davenport, Iowa.
Griffith:Essentials of Woodworking, Manual Arts Press, Peoria, Ill.
Hodgson:Modern Carpentry, Frederick J. Drake Co., Chicago.
Hodgson:Practical Uses of the Steel Square, Frederick J. Drake Co-., Chicago.
Kidder:Architects' and Builders' Pocket Book, John Wiley and Sons, New York.
Kidder:Building, Construction and Superintendence, Wm. T. Comstock, New York.
Radford:Cyclopedia of Building Construction, Radford Architectural Co., Chicago.
Radford:Details of Building Construction, Radford Architectural Co., Chicago.
The National Hardwood Lumber Association:Rules for Measurement and Inspection of Hardwood Lumber, McCormick Bldg., Chicago.