The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California

How To Design And Install Plumbing

When sizing a house sewer for hotels, apartment houses, and industrial and commercial buildings, the accumulated fixture discharge must be taken into consideration. The problem becomes a complicated one involving a certain amount of conjecture. Overlapping of fixture discharge and simultaneous use of fixtures are also important. The task of ascertaining house sewer size, considering these factors, is beyond the capacity of the average installing mechanic. Information has been compiled, however, which is of value. It is set up in chart form and gives unit fixture discharge values. From this information it is possible for him to arrive at fairly accurate conclusions in determining house sewer size.

Trenches in Various Soils. Clay Soil. Very little difficulty is experienced in laying a house sewer in clay soil. The only precaution necessary is that the trench floor be graded properly and that the house sewer be laid in perfect alignment on the solid floor of the trench. See Fig. 48. Care should be exercised in backfilling the trench that no large pieces of ground be permitted to fall on the newly laid sewer.

Sandy or Unstable Soil. When sandy soil is encountered, the laying of the house sewer becomes more complex. The first difficulty the plumber may encounter is caving in of the trench walls. To overcome this, shoring is done. This is accomplished by driving in 1x6 boards, bracing them at close intervals with horizontal 2x4's or jacks of the wedge or screw variety, Fig. 49. If water is encountered, it becomes necessary to pack the shoring with hay or straw, and possibly drive interlocking metal forms.

In such case, it may become necessary to lay the house sewer on concrete or oak plank foundation, as illustrated in Fig. 49. The plumber should work slowly and carefully under these conditions.

House Sewer for Buildings on the Same Lot. One house sewer may serve two buildings located on the same lot. The buildings, however, should be one back of the other and constructed on a lot which cannot be divided by sale. See Fig. 50. It is inadvisable to permit one sewer to serve more than one building under other circumstances.