FLOOR, in carpentry, includes not only the boarding walking upon, but all the timber-work for its support. hoarded floors should never be laid till the building is pro p( rly covered in, nor indeed till the windows are glazed, and he plaster dry. Previous to the lying of such floors, the boards ought to be rough-planed, :ind set out to season, a at least, be tore they are used ; that the natural sap may be thoroughly expelled, and the shrinking prevented, which so frequently takes place when timber is used. The best timber fin' flooring is yellow deal, well seasoned. The quality of this material is such. that when laid, it trill be easily kept of a good colour; whereas white timber is liable to become black in a very short time.
Narrow boards are called battens; these should never exceed seven inches in width, nor be less than an inch in thickness.
Floors are nailed either at both edges, or at one edge : the longitudinal joints, or those in the direction of the fibres, are either square. ploughed and tongued, or rehated and upon each other. Ploughed and tongued, and rebated joints may be used where the apartment is required to be air-tight, and where the stuff is thought not sufficiently seasoned. The heading-joints are either square or ploughed and tongued. In square longitudinal jointed floors, it is necessary- to nail the boards 011 both edges : but where the boards are dowelled. ploughed and tongued, or rebated, one edge °Mr Thav be nailed, as the grooving and tonguing, or lapping, is sufficient to keep the other edge down.
Battens used in flooring are of three kinds, and are dem,• initiated best, second best, and common. The best battens are those that are free front knots, shakes, sap. and cross. grained fibres ; the second best are those free from and sap, but its which small knots are suffered to pass, 'I he common kind are such as remain after taking away the best and second best.
The best floors are dowelled and nailed only at the outer edge, through which the nails are wade to pass obliquely into the joists, without piercing the upper surface of the boards, so that when laid no nails appear : the heading joints of such floors are most commonly grooved and tongued. Some work men dowel the battens over the joists, but it makes firmer work to fix the dowels over the inter-joists. The gauge should be run from the under surface of the boards, which should be straightened on purpose.
In the most common kind of flooring, the board•: are folded together in the following manner : supposing one board already laid, and fastened, a fourth, fifth, sixth, or other board, is also laid and fastened, so as to admit of two, three, four, five, or more boards, between the two, but which can only be inserted by force, as the capacity of the opening must be something less than the aggregate breadths of the boards, in order that the joints may be close when they are all brought down to their places; for this purpose a board may ice thrown across the several boards to be laid, which may be forced down by two or more men jumping upon it : this done, all the intermediate boards are to he nailed down, and the operation is to be repeated till the whole is complete.
This manner of flooring is called a folded floor.
In folded floors, less than four boards are seldom laid together. No attention is paid to the heading joints, and sometimes three or four joints meet in one continued line. equal in length to the aggregate of the breadths of the boards.
In dowelled floors, the distances to which the dowels are set, are from six to eight inches, generally one over each joist, and one over each inter joist; and, as has been already observed, the heading joints of this kind of (loinr are ploughed and tongued ; and no headillg•omL of two boards ought to be SO disposed as to meet the heading•joint of any other two boards, and thereby form a straight line equal to the breadth of the two boards.
In common floors, the hoards are always ganged from the upper side, then rebated from the lower side to the gauge lines, and the intermediate part adzed dmvn, in order to bring them to a uniform thickness. In doing this, great care should he taken not to make them too thin, which is frequently the case, and then they must be raised with chips, which present a very unstable resistance to a pre-sure upon the floor.
Flooring is measured by throwing the contents into square feet, and dividing them by 100, which is called a square qf flooring ; the cumber of hundreds in the superficial contents in feet are squares, and the remainder feet.
The metlud of measuring floors, is by squares of ten feet on each side ; the dimensions being multiplied together, cut off tau figures lion) the right of the prod net, and those towards the left give the number of squares, and the two on the right are feet.
EX AMPLE.—Suppose the length of a floor 25 feet, and the breadth 24.
The product gives six squares, seventy-two feet.
When a naked floor is squared, and the contents found, nothing is deducted for the chimney, because the extra thick ness of the trimmers will make up for that deficiency.