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used, is a stout strip, usually 1 inch by 3 inches, cut diagonally into the outside of the studs and spiked to each. This makes a very strong brace but weakens the studding. The fact that the studs of a balloon frame run from top to bottom requires that the windows should be as nearly as possible over each other, so that one set of window studs will serve for both upper and lower windows.

Erection. The erection of the outside frame should be carefully watched to see that the door and window studs at least are tenoned head and foot, that all the braces are put in and properly framed, and that all the joints are snug and well pinned, the openings in the proper places, and the framing plumb and rigid. Nothing is more annoying than to find, after the outside frame is all up, that a win

dow or door has been framed out of place, and although the builder may be obliged to rectify the mistake at his own expense, it can be done only by patching somewhere and the owner is very likely to feel that the error might have been prevented by the architect's more careful supervision.

Outside Boarding. As soon as the frame is set up, for our house a full frame

which can be set up a story at a time Fig. 23. Use of Ledger Board (the attic joists only being carried on a

ledger), the outside boarding is put on. Spruce or hemlock is used for this mainly, but it must be mill-planed to an even thickness so as to give a true surface for the outside covering of clapboards or shingles. We find that it is specified that the boarding shall be matched and laid diagonally upon the walls, and square-edged for the roof. The reason for not matching the roof is that the cracks in the square-edged boarding allow circulation of air under the roof shingles and preserve them much longer than if matched boarding were used.

Inside Bearing Partitions. When the first-story studding is up and the girts are on, the inside bearing partitions must be erected to give a support for the inner ends of the second-floor joists. It will not be necessary to set up all the studs of these partitions at first, but the partition caps should be run and studs put up at three

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or four-foot intervals, and as nearly as possible in their proper places, to avoid doing the work over again. As soon as this is done, the second-floor joists can be set and bridged and, with the outer walls carried up to the plate and another partition in the second story set, the attic joists may be put on and the building made ready for the roof.

At this juncture we are approached by the foreman who holds in his hand a smooth board upon which he has drawn a sketch of the attic joists and ledger board which he submits for our opinion. We examine his drawings and find that he has represented a ledger board 2x3 inches, notched into the studs one inch and up into the joists two inches, making the bottom of the ledger flush with the bottom of the ceiling furring, Fig. 24. This method he puts forth as having strength nearly equal to the 1-X6-inch board which is generally used, and

2*3*LEDGER the merit of not presenting so broad a surface behind the lathing at the top of the second story, which destroys in a measure the key of the STUDIO plaster. We consider carefully this method in all its aspects and, admitting that it has these features to recommend it, we can praise the ingenuity Van of the device. If we were to run Fig. 24. Section Showing 2- 3-Inch heavy cornices at the top of our second story we should be inclined to adopt the sketch, but as we shall run only a picture molding in the angle which would be helped rather than hurt by the presence of the wood behind the lathing at that point, we decide in favor of the usual way of putting in the 1-X6inch ledger, but tell the foreman to notch the studs 13 inches deep so that there will be a space between the laths and the ledger for a key to the plaster, Fig. 23.

Avoiding Unequal Shrinkage of Timber. An important matter in carrying the outside and inside supports from bottom to top is to see that the amount of shrinkable timber is, as nearly as possible, the same in both outside and inside walls. For this reason the com

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mon practice of setting the partition studs upon a horizontal piece laid on the under floor should be avoided, Fig. 25. For instance, in our case the amount of horizontal wood in the outer wall from the

rigid underpinning to the attic joists will be as follows: the sill, 6 inches; the girt,

6 inches; and the upper part of the ledger STUD

board above its nailings, 2 inches—in all, 14 inches of shrinkable wood. If the

inside partitions were set on a 2-inch sole JOISTS } } resting on the under floor in each story,

there would be in the inside wall, from the

rigid piers in the cellar to the under side ISTUD. of the attic joists, the following amount:

the girder, 10 inches; the two tiers of

floor beams with under floors, 11 inches Fig. 25. Wrong. Way of Setting each; and two soles and two caps, 2 inches

each-making, in all, 40 inches of wood, the shrinkage of which would amount to an inch and a half or more as against a probable half-inch on the outside walls. The result, when the house has become completely dry, would be that the inner end of

the floor beams would be an inch or more lower than the outer end, enough to crack the plastering, and make doors bind in the crosswalls of the second and third stories. The remedy for this is to let the studs of the first story stand on the girders, and the studs of the second story stand on the cap of the first-story partition, and so on, so that the floor timbers do not form a part of the

vertical frame, Fig. 26. This will Fig. 26. Right Way of Setting

give, in the case of our house, an

amount of horizontal wood equal to the girders, at 10 inches, and the two caps at 2 inches each, making 14 inches in all, about equal to the horizontal timber in the outside frame.

Partition

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Partitions running through two or more stories which do not carry floor beams should be built in the same way. Partitions which have no corresponding partitions under them will often occur and will be found in two conditions—those running parallel with the floor beams, and those running across the floor beams. In the former case it will be necessary to set two floor beams under the partition, spaced far enough apart to give a good nailing for the ends of the upper floor boards. In the latter case it will be necessary only to lay down upon the under floor a sole 2 inches thick by the width of the studs.

An important matter in relation to the leveling of the floors is to see that all measurements for sizing-down of the timbers are made from the top of the timber, so that the floor will be level on the top and any inequalities in the depth of the joists can be taken up in the furring. A half-inch will usually be enough to overcome the differences in the depth of the joists so that a series of 10

RAFTER inch joists should be set

COLLAR BEAM with their tops 9] inches above the girder or par· tition cap upon which

Fig. 27. Collar Beam and Purlins they rest.

Roofs. As soon as the attic floor is on, the roofs will be raised. In ordinary country houses the roof should be supported where possible by the interior partitions where these extend down to first-floor girders over basement piers, for in this case no complicated framing or truss work will be required. The usual form of roof consists of a series of rafters supported at the bottom by the plate of the house and at the top by the ridgepole. Intersecting roofs are supported by large timbers. called valley rafters and these should always continue up to the ridge. If the rafters are over 18 feet long it will be necessary to support them near their center; this is done by partitions or by collar beams spiked across

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from rafter to rafter, Fig. 27. In large buildings they are supported by purlins resting on trusses or on posts. The spacing of the rafters varies from 16 inches to 2 or 3 feet, 20 inches being the most usual distance.

For any roof of less than a 30-foot span with the plate securely tied, no interior supports will be needed; for roofs of greater span, purlins should be used. The size of rafters not over 12 feet long should be 2x6 inches; from 12 to 18 feet, 2x7 inches and 2x8 inches; and over that length, 2X10 inches. On the whole it will be cheaper to reduce the length to 10 or 12 feet by means of purlins. An examination of the framing plans shows that our rafters are about 15 feet long and 2x7 inches in size, set about 20 inches on centers. The roof is a hip roof, that is, a roof which draws in from all sides; this is the strongest kind of roof, and we shall not, therefore, have to provide any special supports, and shall only have to

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Fig. 28. Typical Construction for Corners

see that the correct pitch is given according to plans, that the valleys are properly put in and are extended to the ridge or to the hips, and that the openings are of the right size and in the right positions. All portions of the roof must be well spiked together, the ridges perfectly straight and level and in the center, and the rafters all set exactly to a line.

Partitions. With the covering-in of the building finished we may turn to the completion of the inside partitions, and these must be carefully followed to see that the studs are straight and plumb. Crooked studding may be straightened by cutting with a saw on the concave side and then wedging the cut apart. All studs which bear an extra weight, as those at the sides of large openings, should be examined to see that they have a sufficient support on the partition underneath, and do not come between the studs; in case they do, a block should be cut in under the par

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