50
MODERN GASWORKS PRACTICE
stood tliat in no circumstances should the sheets be brought down to ground level. A dwarf concrete wall, about a foot to 18 inches in height, should be provided, the sheets being brought down to the top of this. During recent years there has been. a growing tendency to dispense with. both corrugated iron and massive brickwork, and the light steel-framed house panelled with thin brickwork is making consider-
able headway in this country. An illustration of this type of building, which c a n be effectively u s e d for retort house, engine house, and all classes of buildings, is shown in Fig. 5, where the brickwork is 4| inches thick. The approximate cost, including foundations and roofing, is 5d. to 7d. per cubic foot of contents.
Another very cheap method of construction is tliat which. introduces patent metal meshings, such as expanded metal or “ Hy-rib.” Retort houses and other buildings built up with the aid of such mate-
Fig. 8.—Hy-Rib Metal.
rial are primarily provided with a Steel frame, as in the case of the brick-panelled house, but the open squares between the main framing are filled in with the metal meshing, and the whole is then given a plaster coating. Examples of expanded metal-work are given in
Figs. 6 and 7, whilst the “ Hy-rib ” is seen in Figs. 8, 9 and 10. The plaster is usually composed of 3 parts of Portland cement to II or 12 parts of sand, and the total thickness of the side walls varies from 1 f inches to 3 inches, in accordance with the spacing of the supports. The approximate cost of a building on the “ Hy-rib ” prin-ciple amounts to an average of 5d. to per cubic foot of contents, which includes foundations, sashes, glazing, doors, or roller shiitters. For vertical retort houses this type of structure has proved particularly suitable, this being largely due to the fact that the vertical house may be built far more liglitly than that for horizontal retorts, owmg to there being no heavy floors to support; but it is not to be recommended for buildings having an excessive number of sashes, openings, etc., as the extra cost of providing framing for these is appreciable.