planks set up against the freshly laid wall, there is not only danger of shoving the wall out of plumb, but the bed of chips and mortar which has been prepared is sure to be torn up, and there is no certainty that the stones are properly bedded. Satisfied with the work which has been done so far, we give orders that the filling in against the walls be done with coarse gravel or broken stone, well puddled with water or settled by ramming. Concrete Walls. The custom of using concrete for cellar walls in place of stone is constantly growing. This is a good practice when the concrete is properly made, and it is often, also, a saving of expense over a stone wall. In any case, concrete is the best material for the footing course which bears directly on the ground, as it naturally fills all inequalities in the bottom of the excavation, besides distributing the load better than a footing of separate stones or other materials. Underpinning. The next visit finds the cellar wall complete up to grade and the excavation filled in to the natural level of the ground. While we have no reason to suspect that our instructions have not been followed with regard to facing the wall on both sides, we nevertheless have recourse to the steel rod. Thrusting it down alongside the wall at intervals, we do not find any projecting stones, and as the digging away of the filling in several places shows that the wall is properly cemented on the outside, we feel reasonably sure that the wall is built according to contract. We next take up the question of the underpinning, the portion of the cellar wall above ground which, being visible, must be considered from the point of appearance as well as of strength. A variety of materials may be used for the underpinning. Long pieces of granite or freestone in one or more courses are often used; sometimes an 8-inch brick wall is built upon the stone of the cellar; often the wall already built below ground is continued up to the sill, except that above ground, the face joints, instead of being carefully filled are left without mortar for about 2 inch from the surface, to be filled later with Portland cement mortar, colored as preferred and rubbed with a tool made for the purpose to give either a concave, V-shaped, or raised joint. It is important to see that the underpinning is carried up to the sill the full thickness of the wall, spaces being left for girders, and the top carefully leveled off at the bottom of the sill. FRAMING Sills. While the walls were being built, the carpenters have been at work framing the house and they are now ready to lay the Fig. 18. Construction for Corner of Sill sills and put on the first floor beams. The preparation of the sill consists in halving and pinning together at the corners, Fig. 18, mortising for the door and window studs, and notching out for each floor joist about two inches down into the top of the sill. The sill should be well painted on the underside as a protection against moisture from the wall, but unpainted elsewhere to allow drying out, and it should be set in a thick bed of mortar. As our sill is to set back two inches from the face of the wall, we shall have a chance to point up with mortar along the outside edge to be sure that there is no chance for cold air to get into the floors at this point. Custom allows much variation in the size of the sill, 6X6 inches being the most common size; 6X8 inches is called for in our case, and sometimes the sill is made 6 inches by the depth of the joist. Where large sizes of timber are easily obtainable, this last method is to be recommended. In the first place, the greater depth of timber will span all openings that are likely to occur in the cellar wall, and, besides, the equal depth of the sill and joists leaves no space between the cellar and the vertical wooden wall and prevents, without recourse to brick filling, Fig. 19, the circulation of fire or vermin. The sill may be bolted to the wall, but this is not usual except for light framing in exposed situations. Fig. 19. Proper Construction for Girder Supports. After the sills are set, the next timbers to be put on are the girders which carry the inner ends of the floor beams. They are generally set under the bearing partitions of the house and supported by brick piers or iron columns in the cellar. Brick Piers. Since the piers or columns are not usually set until after the heavy floor beams have been put on, as they would be in danger of being knocked over in the handling of the heavy timbers, the timbers are in most cases supported by shores until the piers are built. Piers of the height of an ordinary house cellar should be 12X12 inches, spaced, according to the size of the girders, from 7 to 9 feet apart. Iron Columns. Where available, iron columns may be used as a good substitute for brick piers. They take up less room and are more easily and quickly placed. For ordinary cellar work, there are in the market columns made of wrought-iron pipes, filled with a carefully prepared cement concrete, which cost less than brick piers. These columns come in convenient lengths, fitted with a cap and base, ready Fig. 20. Diagrams Showing Typical Flush and to set and secure to the timber. From 31-inch to 5-inch sizes are large enough for house work. Girders. The girders are usually 6×10 inches or 8×10 inches for the floors of a wooden house-in our house 8X10 inches. In their vertical position, the girders may be set flush with the floor timbers, in which case each joist is framed into the girder, or they may be dropped to allow the joists to rest on top, usually notched an inch into the girder, Fig. 20. The advantages of the flush framing are that the shrinkage of wood at each end of the joists is equalized, that the circulation of fire by means of the interior partitions is prevented, and that the girder does not take headroom out of the cellar. The advantages of the dropped girder are that the full strength of the girder is available, and that it is possible to run hotair and other pipes up in the partitions without cutting the girder. If flush girders are used, the position of mortises, as well as the position of the mortises in the sill, should be examined by the superintendent to see that the openings framed for chimneys, stairways, etc., are correctly laid out according to the framing plans. Obvious errors will, of course, be easily detected, but it will save much annoyance later if every mortise is verified before the floor is put on. First or Rough Flooring. After the girders are placed the floor timbers may be set. These are usually 2 inches in breadth and for our house are 10 inches deep. Upon these joists is invariably laid, in the East, a rough floor of 3-inch boards either of spruce or hemlock, upon which the workmen can move to carry out all subsequent operations. It has been the custom in the West to omit this under floor, but the saving in expense is very slight and the benefits of the Fig. 21. Proper Method of Bridging Joists double floor are many. In the first place the under floor stiffens the building perceptibly; then it is of great convenience to the workmen, and allows the laying of the upper floor to be put off until the very last thing. This is an important consideration in these days of bare floors and has led to the adoption of the rough under floor generally. It is a good plan to lay this floor diagonally with the joists, as this greatly stiffens the building and gives a more even surface upon which to lay the upper floor. Bridging. As soon as the rough floor is laid, and before this if the boards are to be laid diagonally, the floor beams must be bridged, or trussed as it is sometimes called. This consists in cutting in diagonally between the joists, strips of wood which are nailed securely top and bottom and cross each other between each two timbers, Fig. 21. Some carpenters reason that a piece of plank cut in vertically between the joists will serve the same purpose, but this is not so. If the floor is laid square across the joists, the usual way is to take up a board along where the bridging will come. The superintendent should make sure that the bridging is well fitted, thoroughly nailed, and continuous from side to side. Exterior Framing. Next in order comes the raising of the exterior vertical frame, and in this operation we have a choice between two principles. The first and more common method is called the "full frame" or "braced frame" and consists, first, in erecting at the angles of the building, posts 4×6 or 4×8. Between these uprights, at the level of the floors, are then run horizontal girts which receive the joists of the second floor and into which are framed the door and window studs. At the top of the wall a plate is set in a similar fashion. The angles made by these timbers with the posts, are each braced by diagonal pieces framed or spiked to the horizontal timber and to the post, Fig. 22. BRACE SILL POST In the other method of exterior framing, called "balloon framing", the girts are omitted and the studs run from sill to plate. The usual way of forming the plate in this construction is to spike on the top of the studs a 2-X4-inch piece, and on top of this another 2-X4-inch piece, breaking joints and overlapping at the angles. Provision for supporting the intermediate floors is made by spiking a board 1×6 inches into notches cut in the inside of the studs so that the top of the board will be an inch above the bottom of the floor joists, Fig. 23. board. It is one of the weak points of weight-carrying sense, but because of danger in case of fire, since, being more easily consumed, it does not prevent the spread of the fire as would a solid girt, and would, doubtless, let the floor fall. The floor joists should be notched over this ledger board, which should be kept back a little from the inside face of the studs to allow space for the mortar to clinch. Another weak point in balloon framing is the matter of braces. If used, the braces can be only short ones at the top and bottom, but they are usually omitted. A substitute sometimes Fig. 22. Bracing for Exterior Frame This board is called a ledger balloon framing, not in the 3 |
