COST OF PAINTING. 



439 



of linseed oil. This mixture made 6 gallons of mixed paint of a chocolate color, and gave 1.455 

 gallons of paint for each gallon of oil. 



TABLE VIII. 



AVERAGE SURFACE COVERED PER GALLON OF PAINT. 

 PENCOYD HAND BOOK. 



Light structural work will average about 250 sq. ft., and heavy structural work about 150 

 sq. ft. of surface per net ton of metal, while No. 20 corrugated steel has 2,400 sq. ft. of surface. 



It is the common practice to estimate $ gallon of paint for the first coat and f gallon for the 

 second coat per ton of structural steel, for average conditions. 



The price of paint materials in small quantities in Chicago are (1914) about as follows: 

 Linseed oil, 50 to 60 cts. per gal.; iron oxide, i to 2 cts. per lb.; red lead, 7 to 8 cts. per lb.; white 

 lead, 6 to 7 cts. per lb.; graphite, 6 to 10 cts. per lb. 



A good painter should paint 1,200 to 1,500 sq. ft. of plate surface or corrugated steel or 300 

 to 500 sq. ft. of structural steel work in a day of 8 hours; the amount covered depending upon the 

 amount of staging and the paint. A thick red lead paint mixed with 30 lb. of lead to the gallon 

 of oil will take fully twice as long to apply as a graphite paint or linseed oil. The cost of applying 

 paint is roughly equal to the cost of a good quality of paint, the cost per ton depending on the 

 spreading qualities of the paint. This rule makes the cost of applying a red lead paint with 30 lb. 

 of pigment per gallon of oil from two to three times the cost of applying a good graphite paint, 

 per ton of structural steel. For additional data on paints, see Chapter XV. 



MISCELLANEOUS COSTS. The following approximate costs will be of value in making 

 preliminary estimates. The cost of construction depends so much upon local conditions that 

 average costs should only be used as a guide to the judgment of the engineer. 



MILL BUILDING FLOORS. The following costs are for floors resting on a good compact 

 soil and do not include unusual difficulties. 



Timber Floor on Pitch-Concrete Base. The cost varies from about $1.25 per sq. yd. for a 

 2-in. pine sub-floor and a $-in. pine finish, to about$l.75 per sq. yd. for a 2-in. pine sub-floor and a 

 J-in. maple finish. 



Concrete Floor on Gravel Sub-base. The cost varies from $1.25 to $2.00 per sq. yd. 



Creosoted Timber Block Floor. Creosoted timber blocks 3 in. to 4 in. thick, laid on a 6-in. 

 concrete base, will cost from $2.50 to $3.50 per sq. yd. 



ROOFING FOR MILL BUILDINGS. The following costs include the cost of materials 

 and the cost of laying, but do not include the cost of the sheathing. 



Corrugated Steel Roofing. The weight of corrugated steel roofing and siding may be ob- 

 tained from Table I, Chapter I. The price of corrugated steel may be obtained from current 

 quotations in Engineering News or Iron Age. The cost of laying corrugated steel is about $0.75 

 per square when laid on plank sheathing, $1.25 per square when laid directly on the purlins, and 

 $2.00 per square when laid with anti-condensation lining. The erection of corrugated siding 

 costs from $0.75 to $1.00 per square. Asbestos paper costs from 3} to 4 cts. per lb. Galvanized 



