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By Geo. E. WOODWARD, Architect and Civil Engineer, 29 Broadway, N. Y.
[The papers given below originally appeared in the "Country Gentleman.” Mr. Woodward courteously permits their re-publication here. They will be found worthy perusal by all interested in building.)
In these days of ballooning it is gratifying to know that there is one practically useful, well tested principle which has risen above the character of an experiment, and is destined to hold an elevated position in the opinions of the masses. That principle is the one applied in the construction of what are technically, as well as sarcastically, terined Balloon Frames, as applied to the construction of all classes of wooden buildings.
Since Solon Robinson's description of the mode of building balloon frames, published a few years ago in the New York Tribune, there appears to havo been but little further informatiou furnished on the subject.
Who the originator was is not known; the system is not patented. The first approach in that direction is a plan for a portable cottage or tent, or a . combination of both, published in Loudon's Encyclopedia of Architecture, some twenty years ago. It is more than probable, however, that the balloon frame has been known since the early settlement of the West, or after the demand for a class of buildings above the grade of a log cabin. The settlers on the prairies, remote from timber, now find, as a matter of economy, that fraine buildings are the most desirable, a comfortable log cabin really costing moro money; and from the fact of portable buildings or frames being prepared at the mills or larger towns, and with absolute conditions of lightness for transportation and economy in coustruction, shows pretty conclusively the origin of the so-called Balloon Frames--a frame that, throughout the great West, is almost exclusively used in the construction of every grade of wooden buildings, from a corn-crib to the largest railroad freight depot-adapted to sustaining heavy loads ; entirely secure from lateral thrust; without a mortice or tenon or brace; exposed to all the fury of the prairie blasts, it stands, with more than 30,000 examples of every conceivable size and form, a persect success.
So general is its use west of Lake Michigan and throughout California, that a builder of the old style of timber frame would be regarded with the same sympathy as a man who prefers to travel by stage instead of by rail.
The decreased amount of timber to be used, the whole labor of chopping, hewing and framing dispensed with ; the great economy in its construction, and the ease with which any intelligent man who can lay out a right angle and adjust a plumb line may do his own building, are among its recommendations.
The moment the foundation is prepared and the bill of lumber on the ground, the balloon frame is ready to raise, and a man and boy can do all of it. The sills are generally 3 inches by 6 inches, halved at the ends or corners, and nailed together with large nails. Having laid the sills upon the foundation, the next thing in order is to put up the studding. Take a 2 by 4 stud
of any length, stand it on the corner, set it plumb, and with a couple of stay latbs secure it in position. Nail the stud by four large nails driven diagonal. ly, two on each side, through bottom of stud into the sill. Continue to set up studs on end, 16 inches between centers, around the entire building, and secure each in the same manner. Pay no attention to the length, for they can be readily spliced or cut off when the time comes. Leave the necessary openings for doors and windows. Some prefer to put 4 by 4 etuds alongside the window frames and for door posts, and also at the corners, but they are not necessary, unless the building be a large one. The best plan for corners, and one usually adopted, is to place two 2 by 4 studs close together, so they form a right angle, that is, the edge of one stud placed against the side of the other, so as to form a corner. Next put in the floor joiste for the first floor, the ends of the joists to come out fush with the outside face of the studding; nail the joists, which are 2 by 11, one to each stud at both ends and diagonally through the edge to the sill on which they rest. Next measure the height to ceiling, and with a chalk line mark it around the entire range of studding; below the ceiling line notch each stud one inch deep and four inches wide, and into this, flush with the inside face of the studding, nail an inch strip four inches wide. This notch may be cut before putting up the studs. If the frame be lined on the inside, it will not be necessary to notch the strip into the studs, but simply to nail it to the studding; the object of notching the studding is to present a fush surface for lathing, as well as to form a shoulder or bearing necessary to sustain the second floor ; both of these are accomplished by lining inside the studding-(for small barns and outbuildings that do not require plastering, nail the strip 4 by 1, to the studding)-on this rests the joists of the second floor, the ends of which come flush to the outside face of the studding, and both ends of each joist is securely nailed to each stud; the bearing of the joist on the inch strip below it is close by the stud, and the inch strip rests on a shoulder or lower side of the notch cut to receive it. This bearing is so strong that the joists will break in the center before the bearing gives way. No tenoned joist in the old style of frame will hold half the weight.
The joists being pailed securely to the side of each stud, the lateral thrust caused by heavy weight, as hay, merchandise, &c., is in the direction of the fibre of the wood.
The tensile strength of American White Pine is sufficient to sustain 11,800 pounds for each surtace inch in its cross section. Medium bar iron will sustain 60,000 lbs. per square inch of its cross section surface, so that white pine pulled or strained in the direction of its fibre is equal to nearly one-fifth of the strengih of iron. If, in erecting a building, we can so use our materials that every strain will come in the direction of the fibre of some portion of the wood work, we can make inch boards answer a better purpose than foot square beams, and this application of materials is the reason of the strength of balloon frames.
When the building is designed for storage, it is customary to set an outside strip into the studding at the ends of the building on which to nail the ends of the flooring, so that the thrust of the building endways is in the direction of the fibre of the flooring, and sideways, as before stated, in the direction of the fibre of the joists.
We have now reached the second floor. A third floor, if required, is put in in the same manner. Having reached the top of the building, each stud is sawed off to an equal height; if any are too short they are spliced by placing one on top of the other, and nailing a strip of inch board on both sides. The wall plate, 1 by 4 inches, is laid flat on top the studding, and pailed to each stud; the rafters are then put on; they are notched, allowing the ends to project outside for cornice, &c. The bearing of each rafter comes directly over the top of each stud, and is nailed to it. Put in the partitions, and the balloon frame is complete, and in labor, strength and economy stands unequalled. If lined inside of the studding with common lumber, and clapboarded outside,
it is beyond the reach of harm from any test within the bound of reason, and, I will venture to say, upapproachable in strength and durability by any form of the old fashioned style of frame.
This style of frame can be used with confidence for barns of all sizes, for all manner of dwelling houses, outbuildings, &c., and can be put up by anybody of the least mechanical genius. Io Rural Architecture it is a good desideratum, and although ridiculed by eastern mechanics, it will assume tho same importance that it has and still occupies in the West.
There are many different plans for building these frames. Some lay the first floor, and commence the frame on top of it—others, for smail buildings, put in the studding 4, 6 or 8 feet apart, with horizontal strips between, which is a good plan where vertical siding is used-others tenon the studs and mortice the sills—not desirable, as it injures the strength, makes more work, and hastens the decay of the timber.
A first class balloon sramo should be lined, if for vertical siding, outside the studding—if horizontal siding is used, line inside ; it makes the frame stiffer and the building warmer. Some line diagonally, say from center next the first floor towards extreme upper corners both ways; others line one side diagopally in one direction, and the other in an opposite direction. This makes assurance of strength doubly sure. If lined inside, nail perpendicular lath to the lining 16 inches froin centers, and on this lath borizontally for plastering.
If the house be much exposed, fill in between the studding with brick turped edgeways, and laid in mortar. Put up in this manner the balloon frame building is as warm as any other known style of wooden building. No Hook and Ladder Company could ever pull it down; they might roll it end over end, like a basket, and with as little success of destroying it.
It has been thoroughly tested in every position, and found fully adapted to every known want for which wooden buildings are required, mills and manufactories excepted. Buildings for storage should have timber adapted for their uses; but the cutting of mortices and tenons, and boring augur holes, thus reducing a heavy stick of timber to the strength of one very much smaller, is a decided mistake. If the rural community want stronger buildings at a much less price, let them adopt the balloon frame.
Agricultural societies have offered premiums for nearly every class of agricultural and mechanical productions, but who ever heard of one inviting competition in the art of building, in plans for barns, the various classes of farm buildings and residences, in which department I will venture to say there is a wide field for improvement, and equally as much so in the arrangement as in the construction. We have premium or model farms each year-why not have a model barn, or a model farm house, that shall take a prize, and continue to do so until more successful ones be brought forward ? " Then let their plans, elevations, cost, &c., be published, and we shall at once make a perceptible advance in home comforts and conveniences.
The records of the Patent Office show this country to be profusely supplied with inventive talent; yet a new and original idea in the art of building does not seem to have been put forth. Is it because a plan that promises a decrease in expenses of building, meets with such disfavor among practical men as to prevent its introduction? We plod on in the same old beaten track of our forefathers, with all the faults that a scientific investigation shows to exist, and apparently without an effort or a desire to dispense with useless work, weight and encombrance, and substitute real strength and economy. If architects and practical men would turn their attention to investigating the strength and arrangements of materials, and the improvement of the best existing models of architecture, they would undoubtedly receive the thanks of the building community, who are too often made the means of experimental forays into the field of originality.
The existence of the balloon frame for wooden buildings seems to have been called forth by necessity, and not by the mechanical skill or inventive genius
of any one individual. It has been tested so well as to leave no doubt of its superiority ; its recommendation is its continued use throughout the west, and those portions of our country where its principles are understood. Properly constructed, and with timber adapted to its purposes, it will stand securely against the fury of the elements, and answer every purpose that an old fashioned timber frame is calculated to fulfil.
There is no limit in size or weight to be sustained that the balloon frame is not capable of being used for, and is equally applicable to the same extent as the old style of frame; but the timbers of a barn 50 by 80 must be of a different character than those of a dwelling house 16 by 24.
The timbers of a balloon frame are so arranged and fastened that many of them perform a double duty. The foor beams, ceiling joists, plates, lining, &c., all becomo ties, and do duty in the direction of their fibre.
Fig. 2_Elevation Section-manner of
nailing--A. corner stud, 4 by 4-B.joist, Fig. 1-Floor Plan.
5 by 3-C. 2 by 4. By reference to fig. 1, we see the arrangement of studs and joists, each joist being brought by the side of the stud, and both ure nailed diagonally, or toed to the sill and to each other. The spikes that are driven through the joist are
pointed not only downwards, but towards the centre of the building, so that they form a claw for each joist at its end, the manner of nailing being shown in figs 2 and 3. The single nail, like the single strand of a cable, is comparatively weak, but in numbers there is strength.
The sills for a balloon frame may be as thin as will give a hold to the nail, the main object being to give the studding and
joists a broad bearing on the masonry. The entrance to the Fig. 3-Upper Lating Observatory in this city, was built in balloon style withedge of horst out sills. If the building is to be erected on piers, as is often
done with barns and outbuildings, then the sills should be heavy. Sills on a full foundation are spliced by being halved and spiked together as shown.
Fig. 4 is the side elevation, showing the ends of the joists and their position. The strip, 1 by 4, on which the joists of the 20 floor rest, is notched into the studding as shown in fig. 5, end elevation, but for small buildings this does not require to be let in-the plate, 1 by 4, is nailed to top of studding in the manner shown. The arrangement of joists by changing to opposite sides of studding both ways from center, is not generally practiced, but is recommended as an improvement, as, when the fooring is nailed to upper side of the joist, and the ceiling joists or strips nailed to lower side, there is no possible chance for the building to spread endways, as the studs bear against the joists both ways from centre. The foor joists being toed and clawed with suitable nails and spikes; all lateral or sideway thrusts is in the direction of their fibre.
If the joists are 2 by 9, each joist will hear a practical tensile strain of 17 tons. In theory the compressible and tensile strength of timber are considered equal. The neutral axis of a beam exposed to a cross strain is said to be in the centre, the fibres above being compressed, and those below being separated
Fig. 4—Side Elevation-G. Manner of splicing
Fig. 5—End Elevation. at the same time. Each 2 by 4 stud, when braced by the siding, will be capable of practically sustaining 12 tons. The strip on which the joists rest will sustain nearly three tons by each stud, so that supposing the floor joists to bo equal in strength with the bearings, the floor of a balloon frame building 16 by 24, with 2 by 4 studs. will practically sustain an equally distributed weight of 100 tons, weight of foor included.
The floor joists in a balloon frame may be as heavy as desirable, equal with those used in the old fashioned frame, but they are not injured in strength by cutting tenons.
Some builders of balloon frames notch the under side of the joists, and lock them over the strips. There is no advantage in this, as an extra spike will answer the same purpose, save the work, and preserve the full strength of the timber—4 by 4 studs will be found best adapted to the corners. The manner of splicing studding is shown in fig. 4.
A building designed for storage should be lined diagonally, to prevent a possibility of being thrown out of a perpendicular.
Barns require no lining, except as rendering more comfortable the portions used for horses and cattle—a single strip 4 or 6 inches wide might be nailed to the studding diagonally. Dwelling houses do not require any such strengthening, though diagonal strips add very much to the stiffness of the frame.
The balloon frame is simple in its construction, and from practical experience I give the preference to that form of it which is entirely free from mortices and tenons—that which costs the least labor is the strongest.
Those who adopt the balloon frame for every class of farm building, for wooden houses of every class, will do a sensible thing. For barns of all sizes, tenant houses, lodges, cottages, granaries, corn-cribs, residences, &c., it is the best style of frame known, and the only one used in the great grain growing and stock raising portion of our country west of the great lakes.
The Balloon Frame is one of those innovations, which, like the sewing machine, the busking machine, and the apple-parer, is destined to put an end to those social gatherings, which, in by-gone days, assembled to accomplish by united efforts that which by the advent of machinery is now performed with far greater ease and rapidity.