The only difference between the plumbing system of a small dwelling, such as the cottage house, and the larger systems to be found in large residences, etc., is that it is of a less complicated nature, the rooms being so laid out and the pipes so located that the plumbing of the house is much more centralized than is possible in larger work. It is quite customary in the construction of the cottage house to so arrange the piping that one stack will be able to serve all the fixtures in the house. For dwellings of any description, this stack must not be less than 4 in. in diameter, for it is to receive the discharge from the water closet, for which nothing less than 4-in. pipe should ever be provided, and as the water closet is to be vented usually, a 2-in. main vent is required.

Plate XXX. Plumbing For Cottage House-General Remarks

Plumbing for

Cottage House

Plate 30.

Plumbing For Cottage House General Remarks 84

In the case of two stacks of different size, it is better practice to have the larger one at the house end of the house drain, rather than to reduce after passing the larger stack to the size of the smaller stack.

Thus, in Plate 30, if the house drain were continued to receive a 2-in. stack, and reduced after passing the 4-in. stack, the circulation of air through the system would not be so good as it would be with the 4-in. stack at the end of the line. It is always good policy to centralize the plumbing as far as possible, as any legitimate expedient, looking to the simplification of a system that has now become somewhat complicated, is to be welcomed. It will mean less piping, and therefore less opportunity for defects, stoppages, etc.

The sizes of pipes given in Plate 30 are those which are commonly used, and to which no exception may be taken, unless with the sink and laundry tub, whose waste, according to the requirements of some ordinances, should be one size larger in diameter, which seems to be a wise requirement.

On the plumbing systems of cottages, residences, etc., lead work seems to continue in use to a larger extent than on the work being installed in larger buildings. It must be stated in this connection, that the use of lead is still followed to a large extent in certain sections of the country, the superseding of it by iron and brass being particularly noticeable in the large cities.

For waste pipes the following table of weights may be safely followed:

Diameter of Lead Pipe

Weight per Foot

I

...........................

...............

2 lbs.

1 1/4

" ......................

...................

2 1/2 "

1 1/2

" ......................

.....................

3 1/2 "

2

" .........................

....................

4 "

4

" ....................

....................

6 "

The amount of pressure on street mains must determine the weights of lead pipe proper for supplies, but for ordinary pressures the following table is safe to follow:

Diameter of Lead Pipe

Weight per Foot

3/8

in.........

.....................

1 1/2lbs.

1/2

" ........................

....................

2

5/8

"

...................

2 1/2 "

3/4

"....................

...................

3 "

1

"......................

.................

4

Sheet lead should never be less than 4 lbs., and 6 lbs. for roof flashings is preferable. The tendency to use light materials, owing to the keen competition of the present day, is very marked, and nowhere on the plumbing system more plainly to be seen than in the lead work. Lead bends and drum traps, for instance, are often used which are so fragile that the workman must be careful that in his handling of them they are not crushed. This is true also of the pipe. The weights given above, however, if obtained, will ensure solid and secure work.

The choice of material for water-supply pipes should always be made with due consideration to the chemical properties of the water supply. This is true also in the matter of range boilers. Some waters will quickly attack wrought-iron pipe and boilers, and make renewal necessary in comparatively few years.

Under such conditions, lead or brass supply pipes and copper range boilers should generally be used.

On high-grade work, brass piping is now being extensively used, and for the best work all changes in direction are made by bending the pipe rather than by the use of elbows.