231. Private Residences

Private Residences. It is only very recently that slow-burning construction has been applied to the building of frame dwellings, but it has been found to lend itself so readily to this purpose that the number of "mill-built" houses is increasing every day. Over and above the advantages of decreased fire risk, this system of construction gives the householder a residence warmer in winter and cooler in summer than can be attained by the ordinary balloon or braced frame, while it secures to him walls and floors through which it is absolutely impossible for mice and other vermin to run and breed; and it provides a house the endurance and lasting qualities of which are beyond anything to be secured in any other way, where wood is the material used.

232. Fig. 98 shows the interior of a room in a house built upon the system of slow-burning construction, portions of the floor and partitions being removed to show the relation of the parts. At a is shown the sill 6 in. x10 in. laid in lime mortar on the foundation wall c, while its outside edge has a rabbet cut in it 2 inches deep, to receive the ends of the 2-inch plank b, which take the place of studding in other framing. The sheathing d is ordinary l"x9" plank laid horizontally and thoroughly spiked to the 2-inch boards, while another layer of 1-inch sheathing is applied vertically outside of this, as shown at f. The object of this is to provide a surface to nail the siding g to, which will not throw the clapboards out of even alinement by its unequal shrinkage. If the siding were nailed directly to the sheathing d there would be danger of the clapboards separating in pairs as the boards d shrank in drying out. These three thicknesses b, d, and f also make the side of the house much stiffer and stronger than would the two layers b and d.

Sometimes, for economy of labor, the boards b are made 3 inches thick, and the boards d are laid over them diagonally; the siding is then applied to the diagonal boards.

The inside of the plank b is covered with stiffened wire lath and plastered directly against the wood; the stiffening ribs forming sufficient space for the clinch of the plaster. Grounds j are carried around the room before the plastering is done, and the base i is secured in place before the finished floor is laid.

The floorbeams, one of which is shown in section at k, are 6 in. X 9 in., spaced about 3 feet on centers. They should be planed and finished with sandpaper, the corners neatly chamfered, the surface receiving a coat of shellac varnish before they are set in place (provided that they are thoroughly seasoned), as they will form an open-timber ceiling in the room below, as shown at /. For the same reason the 2-inch plank n which forms the under flooring should be from selected stock, free from sap, shakes, or loose knots, and its under side should be planed and sandpapered before it is laid, as it forms the ceiling in the floor below, as shown at m. Over the underflooring n is laid one or two thicknesses of heavy felt o or a 1-inch layer of mortar, as previously described. The finished floor p is then laid in narrow strips, blind-nailed to the nailing strips and closely driven.

Inside partitions are formed of 2-inch plank set vertically, as shown at r, and plastered on both sides on wire lath, as shown at s. Around all door and window openings is carried a ground t against which the plaster stops, and to which the trim u is nailed.

233. The whole structure is thus rendered solid, substantial, and unyielding to any ordinary strain, while the absence of any small timbers reduces the fire risk to a minimum.

The first cost of this style of construction is greater than balloon frame or braced frame, but the saving in insurance rates and the reduction in the quantity of coal required to heat the house in winter offsets the interest on the extra money invested.

It is imperative that the timbers be thoroughly seasoned before paint, varnish, or other impervious coatings be applied, otherwise the natural sap, being prevented from evaporating, will ferment and cause dry rot. In mill-built structures, it is, therefore, customary to allow the heavy timbers to dry out for two or three years before they are painted.

To insure first-class work in any system of wood construction, it is essential that the wood be thoroughly seasoned, be free from sap, shakes, loose knots, and the other imperfections described. When in position in the building, it must be kept not only dry, but due provision must be made that no portions are so tightly sealed that pure air cannot come in contact with them. Timber thus excluded from pure air, whether in a damp or dry position, will soon rot; so that where impervious layers of paper, felt, etc. are applied, they should be in contact with only one of the surfaces.

234. The following table gives the sizes of timber used in the systems of wood construction of buildings heretofore described. These sizes are not absolute, and vary according to circumstances, but may be taken as a good average where any doubt may exist:

Balloon-Frame Building Not

Over 1,500 Sq. Ft. Area.

Balloon-Frame

Building Over

1,500 Sq. Ft.

Area.

Braced-Frame Building Not

Over 1,500 Sq. Ft. Area.

Braced-Frame

Building Over

1,500 Sq. Ft.

Area.

Slow-Burning Construction.

Corner posts...............

2"

x

4"

2"

x

6"

2"

x

6"

2"

x

6"

and

and

and

and

10"

x

10"

4"

x

6"

6"

x

8"

4"

x

8"

6"

x

8"

Sill..............

4"

x

6"

4"

x

8"

4"

x

10"

4"

x

10"

6"

x

10"

Plate ..............................

3"

x

8"

4"

x

10"

6"

x

8"

6"

x

10"

6"

x

10"

Interties.........

4"

x

8"

6"

x

8"

8"

x

10"

Ledger boards.......

1"

x

4"

1 1/2"

x

4"

Double studs...........

3"

x

4"

4"

x

6"

4"

x

6"

6"

x

6"

2" or 3" plank

Single studs......

2"

x

4"

2"

x

6"

2"

x

4"

4"

x

6"

Braces..........

2"

x

4"

2"

x

6"

4"

x

6"

6"

x

6"

6"

x

8"

Sheathing.................

1"

x

9"

1"

x

9"

1"

x

9"

1"

x

9"

1 1/2" plank, 2 thicknesses

Rough floor......

1"

x

6"

1"

x

6"

1"

x

6"

1"

x

6"

3" to 4 1/2" plank

Finished floor................

7/8"

x

4"

7/8"

x

4"

7/8"

x

4"

7/8"

x

4"

7/8" to 4" plank

Floorbeams.......

2"

x

8"

3"

x

9"

3"

x

8"

3"

x

9"

to

4" x 6" to 10" x 12"

3"

x

10"

3"

x

12"

8'

x

12"

3"

x

12"