There are several methods of anchoring roof trusses to the side walls of buildings. Fig. 26 shows the standard anchorage in which the lower chord of the truss is connected by bolts to the projecting end of a plate built into the wall masonry. Fig. 27 shows an anchorage consisting of bolts set into the wall and attached to a washer plate at their bottoms. Fig. 28 shows a similar anchorage with the washer plate omitted and the bolts held in the masonry by cement. Fig. 29 shows a method of attaching the truss to the side of the wall. As shown by the drawing, the anchor bolts pass through the wall against the outside of which their heads secure a bearing by means of a washer plate. The area of this washer plate in square inches should equal eight times the tension on the bolts in tons. It is important also that the end of the truss should fit tight to the wall, shims being used if necessary to ensure such a fit. The following table shows the diameter of bolt to be used for walls of different thicknesses; the washer plate area in square inches to be allowed for each bolt, and the holding value of the bolt in tons:
Figs. 26 to 32. Typical Wail Anchorages for Roof Trusses.
Area of plate,
5/8 • • •
7/8 • • •
When it is inexpedient to pass the anchor bolts through the wall, as shown by Fig. 29, the anchorage is accomplished by inserting expansion bolts into the wall. The following table shows the holding power of expansion bolts of different sizes:
Holding power in tons for lengths of
Fig. 30 shows the end of the truss built into the wall, the angle clips serving as anchors. Fig. 31 shows the method of anchoring a beam built into the wall; the length of the rod should equal the width of the beam flange plus 6 ins. Fig. 32 shows the manner of anchoring channel beam wall struts. The anchor bolts should be spaced about 3 ft. apart. If the struts are to be anchored to a wall already built the bolts should be run through the wall with washers on the outside, or expansion bolts may be used.
Narrow doors may be made without center styles and wide doors should have two or more spaced from 3 ft. to 6 ft. apart. The rails and styles should be halved together, and they and the diagonals also should have a 7/8-in. chamfer; the sheathings should be screwed on. Fig. 33 shows a door of the construction described. Tables X. and XI. give the proper sizes of material and hardware for doors of different sizes.
Fig. 33. Construction for Narrow DooRs.
Table X. Showing Proper Sizes of Material for Doors up to 14 x 20 ft. in Size.
Size of Doors.
5x/ or less......
5x8 to 7x8
7x8 to 10x10
10x10 to 14x14
14x14 to 14x20
Figs. 34 and 35.
Figs. 34 to 36. Details for Side Window in Brick and Iron Frame Walls.
Table XI. Showing Dimensions of Hinges and Appurtenances for Doors of Different Sizes.
Stanley Works Heavy Hinges.
Size of doors.
3 x 6 or less..
3x6 to 3x8..
3 x 8 to 4 x 10.
4 x 10 to 5 x 12
Over 5 X 12...
Fig- 34 shows the details for a side window in a brick wall. Using 10x12-in. glass, these windows are usually made with from 24 to 40 lights or panes. The sizes of wall openings required for windows with from 24 to 40 10x12-in. lights, are as follows:
No. of lights.
Size of opening.
4x8 ft. 1in
4x9 ft. 1in.
4 ft. 10ins. x 9ft. 1 in
Figs. 35 and 36 shows details of window construction in the side wall of an iron frame building covered with corrugated iron.
Ridge ventilators may be in the form of a monitor roof or they may be round ventilators placed at intervals (Fig. 37). The area of ventilators required per 100 sq. ft. of floor surface for shop buildings of various kinds is given in square feet by the following table:
Height, in ft., above ground.
Machine shop, sq. ft......
Mills, sq. ft..........
Forge shop, sq.ft......
Louvre or open vents.
The areas given in this table are net areas and when louvres are used 60% should be added to allow for the obstruction of the opening by the slats. The areas in square feet of round ventilators of different diameter are as follows:
Area, sq. ft...............................
Details of a monitor roof ventilator with louvres are shown by Fig. 38. Fig. 39 shows details of a monitor roof ventilator with hinged flat iron shutters. These details are for a shutter 8 ft. long. Ordinarily, shutters should be made 6, 7, 8, 9 or 10 ft. long, but intermediate lengths may be used if necessary. The width of the shutters should be the same for all lengths. The shutters may be either of black iron or galvanizd iron. If galvanized iron is used all covering and flashing for the ventilator roof, sides and ends, and all bolts, clips, clinch rivets or other fastenings, any part of which shows on the outside of the covering or finishing, should also be galvanized. Fig. 40 shows a monitor roof ventilator with fixed sash and all iron framing, and Fig. 41 shows a similar construction with movable sash. Figs. 42 and 43 show monitor roof ventilators with fixed and swing sash, respectively, all wood framing. Fig. 44 shows a skylight on roof of monitor made of translucent fabric. It should be noted that the roofing sheets run lengthwise of the building and are 6 ft. 3 ins. x 3 ft. 3 ins. in size. This size of sheet should be used whenever possible, although sheets may be readily cut to smaller sizes. The width of the lap should be 2 ins. and both edges should be securely fastened. For fastening the fabric wire nails 1 1/4-in. long, or 3d nails, should be used; the amount required being 1 1/4 lbs. per 100 ft. of seam. Lap joints or lock joints can be used for all seams, but capped joints can be used only for seams running in the direction of the roof slope.
Fig. 38. Monitor Roof Ventilator with Louvres.
Fig. 39. Monitor Roof Ventilators with Hinged Flat Iron Shutters.
Fig. 40. Montior Roof Ventilator with Fixed Sash.
Fig,. 41. Monitor Roof Ventilator with Movable Sash.
Figs. 42 and 43. Monitor Roof Ventilators with All-Wood Framing.
Fig. 44. Monitor Roof Skylight of Translucent Fabric.
Fig. 45. Single and Double Gutters.
Fig. 46. Types of Fixed and Hanging Gutters.
For Hanging Gutters, Pinch 5/8' Holrs in Purtin to take Hangers, out Edge of Gutter must not Extend above Roof plarne prolonged Hanging Gutter Berger's Patent Adjustable hanger.
Hanging Gutters "D.B" Adjustable Strap Hamger.
Details of Box Gutter.
The sizes of gutters and down spouts and their distance apart for roofs with 1/4 pitch and of different spans are shown by the following table:
1/2 roof span, ft.
Size of gutter, ins........
Size of down spouts, ins.......
Spacing of down spouts, ft........
The slope of gutters should be at least 1 ft. in 50 ft. When the length of the roof overruns the spacing more than 10 ft. an extra down spout should be put on.
Fig. 45 shows details of single and double gutters with both angle and channel purlin connections, and Fig. 46 shows different forms of hanging and box gutters. Regarding hanging gutters it may be noted that ordinarily gutters should slope 1 in. in 15 ft. A 6-in. gutter takes a 4-in. leader and will drain about 3,000 sq. ft. of horizontal surface. A 4-in. gutter will take a 3-in. leader and will drain about 1,700 sq. ft. of horizontal surface. Hangers for hanging gutters should be spaced about 2 ft. 6 ins. apart.