Lighting And Ventilation

A very efficient method of lighting mill buildings is to make the entire upper halves of the side walls of windows with the sash bolted to the framing. In buildings which do not require heating in cold weather, such as forge shops and boiler houses, the lower halves of the side walls may be made of wood panels which can be easily removed to allow ,a free circulation of air and to give clear space for the handling of material. Windows in the sides of monitor roofs admit light to the upper part of the building only; they throw very little light to the floor. Translucent wire cloth may be used for skylights, but it collects dust and smoke and becomes soft in warm weather. In cases where the movement of heavy cranes and the jar of steam hammers and running machinery cause sufficient vibration to break glass skylights, the translucent wire cloth may be used to advantage, but it must be frequently cleaned. Continuous monitor roofs with open sides are usually sufficient to ensure ventilation. In forge shops or other buildings where there is considerable gas and smoke the monitor roof may be rendered much more efficient as a ventilator by placing a line of shutters about 2 ft. high in the side walls at their bottoms. When these shutters are opened an upward draft is secured through them and the open sides of the monitor roof.

Lighting And Ventilation Mill Building 7

Fig.10 a.

Lighting And Ventilation Mill Building 8

Fig.10 b.

Lighting And Ventilation Mill Building 9

Fig. 10 c.

A good common rule for the amount of windows required in the side of a building is to make the window area one-fifth of the walls, or say one-tenth of the total floor area. In place of removable wooden panels for the sides, corrugated iron doors may sometimes be used to advantage. These are built to fill the whole panel and are counter weighted. They can be easily opened, but on account of the counter weights and rigging for hanging them, the cost is considerably more than that of wooden panels. If sash is used in the side monitor for the purpose of securing light, then this monitor should be wide, say one-fourth the whole width of the building, in order to allow light to reach the floor. This arrangement of wide monitor, however, does not secure so good ventilation. The upper part of the roof holds a considerable amount of dead air. To overcome this a second smaller monitor may be placed along the ridge with louvres or shutters on the sides. This arrangement will secure both a light interior and good ventilation.

Estimating The Cost

It has already been stated that the weight of steel frames for mills and similar buildings is from 4 lbs. to 6 lbs. per sq. ft. of exposed wall and roof surface; also that provision for traveling crane adds a weight of about 100 lbs. per lin. ft. of building for every five tons capacity of crane. Other material, such as brick wall, roofing, doors, windows and floors, is very easily figured out in square feet. Hence, with the aid of the following table of prices, the approximate cost of the whole building can be very quickly estimated.

Table Of Approximate Prices

Common brick work........

25 to 35c. per cu. ft.

Rubble masonry....

$5 to $7 per cu. yd.

Concrete......

$6 to $8 per cu. yd.

Cut Stone pier caps......

$2 per cu. ft.

Piles in place...

25 cts. per lin. ft.

Earth excavation.....

50 cts. per cu. yd.

Steel truss and column frame in place.

4 cts. per lb.

Steel beams in place.......

3 cts. per lb.

Plain casting.........

2 " " "

Corrugated iron No. 22, in place, black..

7 cts. per sq. ft

" " " "galvanized....

9 cts per sq. ft

Flashing, galvanized.....

15 " " "

Spruce lumber, in place on floor or roof.

$25 per M.

H.P. matched, in place.....

$35 "

H. P. joist and purlins, on floor or roof.

$30 "

Door frames and doors.....

50 cts. per sq. ft.

Window frames and windows.....

50 " " " "

Sash glazed and painted......

15 to 25 " " "

Gutter and conductor.....

25 cts. per lin. ft.

Stairs, 3 ft. wide, wood

$3 per step.

Stairs, 3 ft. wide, iron.....

$8 per step

Rolling steel shutters......

50 cts, per sq. ft.

Louvres, fixed....

50 " " "

Louvres, moving......

75 " " "

Corrugated iron doors and shutters....

35 " " "

Wire netting, galvanized....

20 " " "

Skylight, 1/4-in. thick glass

25 " " "

Skylight, translucent fabric....

15 " " "

Pipe railing....

50 cts per 1in ft.

Round ventilators......

$3 to $10 each.

Metal cornice.....

10 to 25 cts. per lin. ft.

Slate roof, not including boards...

$7 to $12 per sq. of 10 x 10 ft.

Slag and gravel roof, not includ'g boards.

$5 " $7 " " "

Prep'r'd comp'sit'n roof, n't incl'd'g b'ds

$2 " $5 " " "

Wood shingle roof, not including boards.

$3 " $5 " " "

Tin plate roof, not including boards....

$ 10 " $12

Corrugated iron roof........

$ 7 " $9 " " "

Roughly speaking, the cost of one-story iron buildings, complete, is, for sheds and storage houses, 40 to 60 cts. per sq. ft. of ground, and for such buildings as machine shops, foundries, electric light plants, that are provided with traveling cranes, the cost is from 60 to 90 cts. per sq. ft. of ground covered.