CHAPTER IIMain Frame

Fig. 16. Full Frame House

9. Methods of Framing the Superstructure.—In the early days when lumber was plentiful, houses and barns were framed in what is known as "full frame." Such frames consisted of heavy and solid timbers mortised and tenoned and pinned together, Figs.16and17. With the growing scarcity of lumber the "half frame" ofFig. 18became common. This latter type, it will be seen, makes less use of heavy timbers and wooden pins, and more use of planks and nails. To-day the vast majority of buildings, where wood is the material used, are constructed by what is known as "balloon framing" in houses and "plank framing" in barns, Figs.19and20. In view of this, attention will be directed to balloon framing only. One who is able to frame a house should have no trouble with plank barn framing, where drawings show the details.

Fig. 17. Heavy Timber Barn

It must be understood, too, that there are quite a variety of ways of framing a balloon and a plank frame. It will be possible in this chapter to treat of but one type. A mastery of this one type should enable the student to work out other types, with suitable detailed drawings provided him.

10. Sills and Girders.—InFig. 21will be found illustrated three types of box sill construction. Whatever the sill used, care must be taken to so plan that mice may not have free access to the various parts of the building. If the sill does not inhibit, then blocks should be spiked between the studs. Such blocks serve as fire breaks.

Fig. 18. Half-Frame House

Fig. 19. Balloon Frame House

Fig. 20. Plank Frame Barn.

Fig. 21. Three Types of Box Sills

The bed plate of the box sill should be selected from stock with straight edges. In the framing of joists, plan so that the crowning edges shall be up when in position, and in placing the joists see that the most crowning are in the middle of a room. Joists are fastened to their sills as inFig. 21.

Fig. 22-aillustrates a built up girder, and the manner of framing the joists to it. Three 2" × 10"'s with a 2" × 4" attached to each side, the whole thoroughly spiked together, form the girder. The advantage of this type of girder lies mainly in the fact that it leaves the headroom of a basement clear, which is not the case in the type shown inFig. 22-b. This second type is somewhat easier to frame, and is therefore greatly used where the owner does not object. It is better where furnace stacks must be placed in a partition above it.

First floor joists, like second floor joists and studs, should be spaced 16 inches from center to center, beginning at one side or end of a room. Not to make such provision would cause a waste in lathing, since the lath are all 4 feet in length, a multiple of 16 inches. Any remainder after such a spacing should be allowed to come at the side or & end of the room.

Fig. 23. Cutting Bridging

11. Bridging.—To add to the carrying power of floor joists, bridging is cut in between them as shown inFig. 23.For ordinary dwellings 1" × 3" stock will serve. On large work, stock two inches thick should be made use of. Bridging should be spaced notmore than 8 feet apart. A miter-box, set at the appropriate angle, may be used in cutting bridging, all the pieces being cut at one time with the exception of those for the odd spacings at the side or end of a room. A more common practice is to take a piece of stock, and, after cutting a bevel on one end, place it as inFig. 23with the beveled end above the lower edge of the joist against which it rests, a distance slightly in excess of the thickness of the stock; then saw as indicated, sawing vertically and along the joist.

Fig. 24. Laying off a Stay

Fig. 25-a-b. Headers and Trimmers in Floor Frame

Before placing bridging, the joist must be spaced and properly fastened in place. This is done by placing a piece of stock, 1" × 6" or 2" × 4", as inFig. 24.With a try square, mark the locations of the joists. This board may then be transferred to the center of the room and the joists there spaced according to the marks, and held in place by being "tacked." A second method consists in placing the spacing board in the center of the room and having a second person sight the joists for straightness while the first party places them as directed and tacks them. This tacking consists in driving the nails only partially in, leaving the heads project enough that they may later be withdrawn with a claw hammer. Still another method is to lay off the "stay" by measurement with the framing square so that it corresponds with the spacings of the joists at the side walls.

Bridging should be nailed with two nails at each end of the piece.

Fig. 26. Placing Headers and Trimmers

Fig. 27. Floor Frame and Rough Floor

12. Trimmers and Headers.—In the making of stair and chimney openings it becomes necessary to support the ends of joists other than in the usual manner. This is done by cutting in headers as in Figs.25,26and27. Where the span is not great, such as at an ordinary chimney inresidence work, in which but one or two tail beams are to be carried, headers are not doubled and are merely spiked in place. Where many joists are to be carried, headers or trimmers, or carrying joists must be doubled. Iron stirrups or hangers should be used instead of spikes in joining headers to carrying joists where spikes would weaken the carrying joist and would not give

sufficient strength to the joint. Except upon long spans, tail beams are usually fastened to the header by spiking only. On long spans they should be framed to the header as joists are framed to a girder, a 2" × 4" being spiked firmly to the header as a support.

In determining the amount of space to allow for head room in framing about a well hole for a stair, determine the run and rise of the stair from the plan and elevation, and then plan to allow at least 6' 6", measured from the proposed nosing line of the treads up to the proposed location of the trimmer, or carrying joist, or header, as the case may be, at the ceiling level,Fig. 121.

Fig. 29. Headers and Trimmers in Wall Frame

Fig. 30. Stud and Joist Patterns

The term "header" is also used to designate the studding, or joist in the case of double doors, placed horizontally over window and door openings,Fig. 28.Studding cut in below window openings forms the stool, also known as header. The illustration shows the manner of framing for openings of different widths. A small single window may require but one thickness of 2" × 4". A medium sized opening will have a header of two pieces of 2" × 4". Wherethe opening is rather large, as in the case of double door openings, two joists will be set on edge over the opening as header.

13. Walls and Partitions; Joists and Rough Floors.—A study of Figs.16,17,18,19,20and29should give an understanding of the essential members of the framed wall of a building, and their relations one to another.

Whether side walls shall be framed and raised before the rough or false floor of the first story is laid will depend upon the type of sill construction made use of. In laying off studs, joists, etc., a pattern is first framed. These patterns are afterward used in the building and are therefore counted in with the total number of pieces to be framed. To these patterns, stops and fences are attached near the two ends and at the middle,Fig. 30.The other studs or joists of similar dimensions are laid off one at a time by superimposing these patterns and marking about them with pencil,Fig. 31.

Fig. 31. Marking Joists from Pattern

Fig. 32-a.

Fig. 32-b.

Fig. 32-c.

Ribband or ribbon boards and plates are laid off by placing them alongside the "lay-out" for the studs made upon the sills, and transcribing the marks to the ribband board and plate by means of try-square and pencil. Sometimes ribband boards and plates are laid off by measurement, as are sills.

Fig. 33. Corner Post Being Plumbed and Stayed

Corner posts are constructed first and placed.Fig. 32-ashows a section of a corner post which has much to commend it.Fig. 32-billustrates a more common type of construction. The most serious objection to this type is the fact that the post must be furred after the lather has placed the lath upon one side of the room. Corner posts are plumbed and stayed in two directions, after being raised,Fig. 33.Either 2" × 4" or 1" × 6" stock will be used for stays. With the corner posts set, the ribband boards are placed. Where the span is too long for any available length of ribband board, in laying out the ribband boards provision must be made for their "breaking" joints upon studs. These studs will be raised immediately after the corner posts, the ribband board attached to corner post and stud, after which the stud will be plumbed and stayed,Fig. 34.Studs are framed before being raised so that ribband boards may be "let into" them as shown inFig. 34.Second and third floor joists will be notched to slip over these boards and will be spiked to the studs in addition. Remaining studs areplaced one at a time, one man setting up and nailing the foot while another fastens the ribband board to the stud at the second floor line,Fig. 35.

Fig. 34. Side Wall Stayed

With the completion of the raising of the two outside walls which are to bear the joist ends, the middle partition, should there be one, paralleling these walls should be framed and raised. Aslightly different procedure from that just described is followed, that is, instead of raising one stud at a time the whole partition is framed and nailed together upon the floor, even to the cutting in of headers, etc. When a section such as the number of men available can raise is ready, the same is raised, and stayed after being plumbed. The studs of partitions are framed but one story high and "plated" at such a height that second floor joists may be placed thereon in splicing. Just as far as possible first and second floor joists should be spaced to rest one directly above another and in line with the supporting studs of partitions so that furnace stacks may be placed with ease. If joists rest upon partition plates and not directly above studs, a double plate must be made use of.

Having placed the second floor joists, the studs at the ends of the house may be set up. Their locations will be marked upon sill and upon second floor joist which is to be placed at the end of the house. This marking is best done by placing the joist upon the sill and transcribing the marks laid out upon the sill to the joist, after which it is to be raised into place.

Fig. 35. Setting up Studs and Attaching to Ribbon Board

Double plates will next be framed. They should break upon studs and be marked by transcribing the marks for the studs from the sills. At the corners the plates will be framed with butt joints, the second set lapping over the joints made by the first plate.

Next, the sustaining middle partition of the second story is raised as was that of the first story. The attic floor joists are placed as were those for the second floor.

All walls and partitions are now "lined up," that is, any irregularities are taken out by additional stays.

Fig. 36. Estimating Window Openings

False or rough floors are laid in the various stories where not already placed, bridging being placed and openings for stairs and chimneys framed. Such floors are laid either diagonally or straight across the joists. The diagonal floor is considered better,Fig. 27.

14. Openings in Framework.—Studs in outside walls are set without reference to openings for doors and windows. Such openings are cut and headers and stools placed after the walls are up and ready for sheathing. The seeming waste occasioned by this method is slight since the cut-out material is available for headings, etc. Most carpenters make a story pole to be used in laying off window and door heights in cutting out studs. This is nothing more than a piece of 1" × 2" or 1" × 3" stock with the heights of the openings from the rough floor or from the joists, where the rough floor is not laid, marked plainly thereon. This pole is placed alongside the stud to be cut and the mark transcribed from pole to stud.

Beginners are frequently troubled in determining the proper opening, even when the size of the window is specified. In general, carpenters plan to have the studs on either side of an opening, either door or window, so set that the outer edges of the exteriorcasings will break upon their centers. Windows are specified by the width and height of their glass and the number of divisions or lights, width always being specified first. The distribution of excess measurement due to the meeting rail, top and bottom rails, side rails or stiles is shown inFig. 36.Rail and stile widths and sash thicknesses will vary from those given when any very great increase in size of window is made. Manufacturers of sash and doors provide catalogs in which stock sizes are listed.

Fig. 37. Framing Wall Openings

Estimate an opening vertically,Fig. 36, thus: Sill, 2"; subsill, where frame is made with one, 1"; bottom rail, from edge to bottom of rabbet, 3"; glass in lower sash, 34"; meeting rail, from rabbet to rabbet, 1"; glass in upper sash, 34"; top rail, 2"; space for head jamb and lugs of side jambs, 2" or 3"; total, 79". A carpenter would say, "Add 11" to the glass measurement to get vertical height between stool and header." Window sashes with muntins require an addition of ¼" for each muntin. The thicknesses of header and stool must be considered in addition to the measurement just mentioned when studs are sawed,Fig. 37.

The width between studs would be estimated thus: Width ofglass, 28"; width of stiles, from rabbeted edge to outer edge, 4"; width of casings, 8"; total 40", distance from center of stud to center of stud. Comparing this with the width of glass it will be seen that the difference is 12". A carpenter, therefore, makes use of a general rule: Add 10" to the glass measurement to get distance between studs, where a 4" or 4½" casing is used with this type of window frame.

Fig. 38. Threshold Detail

For the 3' x 7' door, Figs.37and38, estimate the opening as follows: Height of door, 7'; allowance for rough floor, ¾"; finish floor, ¾"; threshold, ⅝" to ¾", head jamb and space for lugs of side jambs, 2" to 3"; total from joist, may be 7' 5".

For the width of opening estimate: Width of door, 3'; width of casings, at 4½" each, 9"; total spacing of studs center to center, 3' 9". Distance between studs will be 3' 7". This will leave space enough to put the doubling studs on each side between header and floor. Since locations of openings in the main frame, both window and door, are dimensioned to the centers of the openings, it is easiest in laying off to estimate from the center each way rather than to estimate total width.

After these openings are made, the frame of the house may be covered with sheathing, or the roof may be framed; both orders of procedure are common.

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