CHAPTER XIX

PLUMBING

SINCE there is very little building work which can be satisfactorily completed without the use of lead in some form or other, it is necessary to devote a chapter to this important subject of plumbing. As in sundry other departments of building construction, it would be possible to write very extensively upon lead work; however, there is a very great deal which need not be touched upon in a work which is particularly applied to farm and estate building construction.

Lead is prepared and produced in two marketable forms :

1. Cast lead, which is run in a molten condition into sand moulds resulting in sheets of about 6 feet wide and 16 to 18 feet long. This variety is used where greater strength is required, but is subject to irregularities in thickness and what are called sand holes-the result of the molten lead forming bubbles.

2. Milled lead, which is produced by rolling ' pigs' of lead out into sheets of uniform thickness, which can be varied by the adjustment of the rollers. These sheets are 7 to 8 feet wide and 30 feet long. The thickness varies according to the purpose for which the lead is to be used, the usual weight for different purposes being as follows::

Wherever lead is to be laid in areas larger than those of flashings, ridges, hips, &c., a prepared boarded surface has to be made, having no sharp angles or projections and planed to a smooth surface. To allow for contraction and expansion no greater length than 12 feet in one piece should be laid, which necessitates junctions between the sheets. This is usually done by planed and rounded wood rolls, fixed to the surface of the boarding, over which the adjoining sheets

U

of lead lap in such a way that the roll is passed on each side by about 3 inches of a double thickness of lead. Another method is by placing the two overlapping ends side by side vertically and then folding or rolling them over and over till they touch the surface of the lead flat (Fig. 205). The use of lead in valley gutters-i.e., the points where the downward slopes of two roofs meet-is very usual. The gutters may be either tapering or box gutters. The latter type is cheaper and quite satisfactory, as the width of the gutter does not alter throughout its length, whereas in the tapering variety, the longer the roof the higher, and therefore the wider, must be the lead. In both cases, however, as will be seen from the diagrams, the method of laying is very similar-that is to say, a boarded surface is prepared and carried upon supports fixed to the feet of the rafters. The box gutter, however, requires vertical sides in addition, and the tapered gutter a series of drips, which are steps of 1 inch high, across the width. The lead at the sides of both types of gutters is

FIG. 205.

dressed up under the roof covering to make the joint perfectly watertight (Figs. 206, 207, 210).

Flashing is a system of providing by the use of lead and sometimes cement a water-tight joint at such positions as that where a chimney stack emerges from a roof, or where a roof light abuts on the tiles or slates. On the lower side of any such construction the lead having been fixed to the face of the brickwork or timber is dressed down compactly and taken over the roofing so that the rain-water is thrown over the tiles or slates below and clear of the joint. Above, the lead is dressed up underneath the roofing material and sloped either from the middle to the two ends or from one end to the other of the back of the chimney stack, roof light or whatever it may be, in order to conduct the water on to the surrounding roof. The sides remain to be rendered waterproof, and this is done by dressing the lead in raking or stepped flashings and fixing in the joints of the brickwork and down to the level of the sloping roof, either projecting for 3 or 4 inches over the slates or tiles or underneath forming a secret gutter constructed as shown in the diagrams (Figs. 208, 209).

The junctions of lead pipes also form an important part of a plumber's work, the two most generally employed being

1. A blown joint which consists of the ends of two pipes being respectively opened and filed down to fit each other, the space between the two ends being filled with solder composed of one part of lead and two of tin (Fig. 212).

2. A wiped joint, used for pipes of larger diameter than above. The ends of the two pipes to be joined are prepared as in the blown joint, but the amount of solder-which in this case is composed of 1 or 2 parts of lead to 1 of tin-extends about 2 inches above and 2 inches below (4 inches in all) the junction. The solder is carefully poured in and wiped round, the operation continuing until the joint presents the appearance shown in the diagram (Fig. 211).

CHAPTER XX

SPECIFICATIONS, ETC.

In all cases where any building work has to be done, no matter of what size, it is nearly always necessary for the architect, or at any rate him who is responsible for the design and arrangement, to specify in writing every detail in connection therewith. For this purpose it is desirable for those who may at some time or other find themselves in such a position of responsibility to know how a specification is composed in the clearest and quickest way. Having once laboured through the building up of a specification, all subsequent compositions can well be based upon the original, and all necessary alterations in detail made according to the intentions of the designer.

Firstly, it is necessary to subdivide the whole specification into the various trades which it will be necessary to employ-such as excavator, mason, bricklayer, carpenter and joiner, glazier, &c., as shown in the specifications of either the stables or cowhouse or any of those given in this volume. This being done each trade is taken separately and every detail entered seriatim under its correct trade. As will be seen on reference to the specifications mentioned above there are sundry somewhat important preliminary and general clauses with which the specification should commence, chiefly when the work in question is to be let out to contract; and the builder chosen to carry out the work, either as a result of his tender being the lowest or by reason of his good reputation, is then easily able to comprehend his responsibility, and the specification and drawings form an agreement by which both he and his employer must stand.

There is a variety of ways in which a specification may be worded, some being somewhat verbose and others abrupt. A very usual method of writing such is instanced in those specifications already referred to.

Were it possible to clearly show in the drawings of some projected building every detail of construction and arrangement no specification would be necessary, but as can be readily understood this is not possible, and it is therefore the custom to consider the drawings and specification simultaneously, and that which is not shown or stated