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Vertical or dead shores are in general use for the following cases: (1) When the foundations of a building have given way and it is necessary to support the walls by shoring in sections so as to underpin them during the renewal of the foundations. (2) When the ground storey of a private house is converted into a shop, the upper part of the house is supported by shoring until the bressummer is fixed in its place and the new brickwork built upon it to support the old wall. (3) Where it is desired to raise the front of a shop, then it is necessary to support the upper part of the structure whilst a new bressummer or girder is being fixed in position so that it can carry the wall above. In larger and more important classes of buildings, which range from three storeys high upwards, it is usual, in addition to dead shores, to use raking shores, with the object of steadying the walls, as well as giving a certain amount of support, and thus to minimise the chance of accident to the building.

Dead Shoring for Converting Private Dwelling into Shop.

Figs. 808 and 809 represent a usual method of shoring in the common case of converting the ground storey of a small private dwelling house into a shop. In many cities, for such small jobs as this, raking shores are not used. The leading methods of procedure may be summarised as follows: The windows are strutted by pieces of timber about 3 in. by 3 in. or 3 in. by 4 in. The sill shown at is supported on the ground floor, and a head is put plumb over this against the ceiling, as shown at  (Figs. 808 and 809); three or more vertical posts are cut to a length to fit tightly between the head and the sill. Sometimes the posts are cut a little short so as to allow of a pair of oak wedges to be driven between the post and sill; in this way the dead shores or posts support the floor, and thus the front wall is relieved of its weight. Holes are then cut through the front wall about 6 in. or a foot above the floor, for the insertion of needles (Figs. 808 and 809). It is usual to put a needle under each pier between openings, but when the piers are very wide it is sometimes necessary to insert two needles, as shown in the illustrations. The needles are supported by dead shores at each end (Figs. 808 and 809), both inside and outside the building. These shores rest upon continuous sills, and are fixed tight under the needles by the insertion of oak wedges. It is usual to brace the outer dead shores to the needle by a piece of scantling as shown at. The feet and head of the shores are also secured to the head and sill by iron dogs. Next, it is usual to remove sufficient of the brickwork to allow of the insertion of the bressummer which spans the opening and to which the floor joists are fixed in some one of the various ways. Next the walling is made good, with brick or stone laid in Portland cement, as far as this can be done without removing the needles; after the new work has properly set the shoring is removed, and the making good of the wall is completed. When placing the shores on the ground floor it should be carefully noted whether this is sufficiently strong to support the shoring. If not, part should be taken up and the sills bedded firmly on the solid earth. In the case where there is a basement it would be necessary to support the ground floor by a sill-head and dead shores, as shown in Figs. 808 and 809. With small jobs, sometimes the inner standard supporting the needle is dispensed with; pieces of square timber about 3 ft. long, (Fig. 809), rest on the floor directly over the head ; the inner end of the needle rests on these square timbers; and if required, pairs of wedges are driven between the timber and the needle, as indicated at.

Shoring Large Corner House for Converting the Ground Storey into Shop.

A familiar example, but not such a common one as that just described, and one that is of much greater magnitude, is illustrated by Figs. 810 to 815. A case of this description generally calls for the exercise of considerable skill and judgment, especially if the house is an old one. Figs. 810 and 811 show a five-storey corner house, with an area on the two fronts. It is shown shored up for the conversion of the ground