428 ESTIMATES OF STRUCTURAL STEEL. CHAP. XIII. 



Doors shall be estimated in sq. ft.; state whether sliding, lifting, rolling or swinging. Steel 

 doors covered with corrugated steel shall be estimated by including the steel frame under steel 

 and the covering with corrugated steel siding. State style of track, hangers and latch. 



Skylights shall be estimated in sq. ft., giving kind of glass and frames. 



Operating devices for pivoted windows or louvres shall be estimated in lineal feet. 



Lumber shall be estimated in feet, board measure, noting kind. Note that lumber under 

 I in. in thickness is classified as I in. Above I in. it varies by j in. in thickness, and if surfaced 

 will be i in. less in thickness, i. e., if in. sheathing is actually if in. thick, but shall be estimated 

 as if in. Lumber comes in lengths of even feet?; if a piece 10 ft.-8 in. or n ft.-o in. is required, a 

 stick 12 ft.-o in. long shall be estimated. In using lumber there is usually considerable waste de- 

 pending upon the purpose for which it is intended. In estimating tongue and grooved sheathing 

 10 to 20 per cent shall be added for tongues and grooves and from 5 to 10 per cent for waste, 

 depending upon the width of boards and how the sheathing is laid. 



Composition roofing or slate shall be estimated in squares of 100 sq. ft., allowing the proper 

 amount for overhang at eaves and gables and for flashing up under a ventilator or on the inside 

 of a parapet wall. 



Tile roofing or slate shall be estimated in squares of 100 sq. ft., adding 5 per cent for waste. 

 Include in an estimate for tile roof, gutters, coping, ridge roll, plates over ventilator windows and 

 plates under ventilator windows, these being estimated in lineal feet. Flat plates for the ends 

 of ventilators shall be estimated in sq. ft. 



Brick shall be estimated by number. For ordinary brick such as is used in mill building 

 construction, estimate 7 brick per sq. ft. for each brick in thickness of wall, i. e., a 9 in. wall is two 

 bricks thick and contains 14 brick for each sq. ft. of superficial area. 



Always note whether walls are pilastered or corbeled and estimate the additional amount of 

 brick required. If walls are plain, no percentage need be added for waste, but if openings such 

 as arched windows occur add from 5 to 10 per cent. 



Concrete shall be estimated in cubic yards. Walls or ceiling of plaster on expanded metal 

 shall be estimated in squares of 100 sq. ft., noting thickness and kind of reinforcement. Rein- 

 forced concrete floors shall be estimated in sq. ft. of floor area, noting thickness and kind of rein- 

 forcement. Paving of all kinds is estimated in square yards, but the concrete filling under the 

 pavement itself is estimated in cubic yards. Concrete floor on cinder filling is usually estimated 

 in square yards, specifying its proportions. 



ESTIMATE OF COST. The different types of framed steel structures vary so much with 

 local conditions and requirements that it is only possible to give data that may be used as a guide 

 to the experienced estimator. The cost of steel frame structures may be divided into (i) cost of 

 material, (2) cost of fabrication, (3) cost of erection, and (4) cost of transportation. 



i. Cost of Material. The price of structural steel is quoted in cents per pound delivered 

 f. o. b. cars at the point at which the quotation is made. Current prices may be obtained 

 from the Engineering News, Iron Age or other technical papers. The present prices (1914) 

 f. o. b. Pittsburgh, Pa., are about as follows: 



TABLE I. 

 PRICES OF STRUCTURAL STEEL (1914) F. o. B. PITTSBURGH, PA., IN CENTS PER POUND. 



Price in Cts. 

 Material. per Lb. 



I-beams, 1 8 in. and over 55 



I-beams and channels, 3 in. to 15 in 45 



H-beams, over 8 in 60 



Angles, 3 in. to 6 in. inclusive 45 



Angles, over 6 in 50 



Zees, 3 in. and over i .45 



Angles, channels, and zees, under 3 in 1.40 



