| Size | Thickness, inches | Weight per ft., pounds | Depth of socket | Annular space |
|---|---|---|---|---|
| 3 | 1⁄2 | 7 | 11⁄2 | 1⁄4 |
| 4 | 1⁄2 | 9 | 15⁄8 | 3⁄8 |
| 5 | 5⁄8 | 12 | 13⁄4 | 3⁄8 |
| 6 | 5⁄8 | 15 | 17⁄8 | 3⁄8 |
| 8 | 3⁄4 | 23 | 2 | 3⁄8 |
| 9 | 13⁄16 | 23 | 2 | 3⁄8 |
| 10 | 7⁄8 | 35 | 21⁄8 | 3⁄8 |
| 12 | 1 | 45 | 21⁄4 | 1⁄2 |
| 15 | 11⁄8 | 60 | 21⁄2 | 1⁄2 |
| 18 | 11⁄4 | 85 | 23⁄4 | 1⁄2 |
| 20 | 13⁄8 | 100 | 3 | 1⁄2 |
Terra-cotta pipe should not be permitted in filled-in ground.
Roots of trees find their way into the pipe through cracks or cement joints. When the roots get inside of the pipe they grow until the pipe is stopped up. As the roots cannot be forced or wired out, the sewer must be relaid. The writer has seen a solid mass of roots 10 feet long taken out of a tile sewer.
In case terra-cotta is laid in filled-in ground, there is only one way to insure the pipe from breaking. The pipe should be laid on planks. Then, if the ground settles, the pipe will not be broken.
WATER CONNECTION AND SERVICE
Tapping Main.—The water service for a building is put in at the same time as the sewer is connected and run into the house. For a 11⁄4-service pipe a 1⁄2-inch tap is furnished. The water company taps the main, at the expense of the plumber, and inserts a corporation cock.
Digging Trench.—The trench for the water main should be dug at least 41⁄2 feet deep or below frost level and the trench should be kept straight. When the sewer is put in at the same time, one side of the sewer trench can be cut out after it is filled up to the level of the water main. The water pipe can then be laid on this shelf at least 2 feet away from the original trench of sewer. Sometimes the surface of the ground must not be disturbed. In this case small holes are dug and the pipe is pushed through or driven through under that portion not dug. These places are often tunnelled (see [Fig. 42]).
In digging in city streets, care should be taken not to destroy any of the numerous pipes encountered.