For brick vault arches, the cost of labor, exclusive of mortar, will be about $5 per thousand brick. If pointed underneath, 7 cents per square foot will have to be added. If the centers are left in place until the mortar has set, it will be necessary to rake out the joints and wet them before pointing. This will cost about 10 cents per square foot. TERRA-COTTA WORK =38. Terra-Cotta Floor Arches.=—The cost of =terra-cotta floor arches= varies somewhat with the span and with the difficulties encountered in putting up and removing the centering. If the building consists of a number of stories, the centering that is used on one floor may be reused on a floor several stories higher up, in this way decreasing the outlay for centerings. For ordinary spans, the following analysis of the cost of a 12-inch arch, exclusive of the cost of the terra cotta itself, will be found quite accurate, provided the centering is put up by experienced laborers. The price given is per square foot of arch. CENTS Centering 3 Hoisting and laying 3½ Mortar ½ ----- Total 7 This price is for work showing a flat ceiling. If the ceiling is much broken up by girders, the price, exclusive of the terra cotta itself, will be about 8 cents per square foot. As a price per square foot, including the cost of terra cotta, setting, and mortar, the following figures may be taken. These, however, do not include the cost of plastering, or of any concrete fill above the terra cotta. CENTS 10-inch arches 23 12-inch arches 25 15-inch arches 29 =39. Terra-Cotta Partitions.=—In office buildings, =terra-cotta partitions= are usually erected on top of a floor in order to divide the space into such rooms as will suit the tenants. This work is generally done after the building is otherwise completed. An analysis of the cost of such partitions is given in Table V. TABLE V COST OF TERRA-COTTA PARTITIONS =========+===============+=============+============== Thickness|Cost of Setting|Cost of Terra|Total Cost per Inches | per Square | Cotta per | Square Foot |Foot, Including| Square Foot | Cents | Mortar | Cents | | Cents | | ---------+---------------+-------------+-------------- 3 | 5 | 9 | 14 4 | 5 | 10 | 15 6 | 6 | 12 | 18 10 | 8 | 16 | 24 =========+===============+=============+============== The cost of placing 8-inch, terra-cotta backing to brickwork is 6 cents per square foot. TILING