Koshland House

The nearly 18,000 square foot, three-story building (above a partially submerged basement) is approximately sixty feet wide by seventy-five feet deep. It is of brick construction with a Colusa sandstone veneer. The sandstone is regular ashlar blocks, l'-6" x 5'-0" generally, 4" thick, tied onto the structure with wrought iron or mild steel cramps.[6] The exterior face of the block and carved ornament is dressed in a regular horizontal pattern of grooves called broaching, or broached ashlar. The presence of a fine red lichen growing on the stone gives the building a pinkish cast.[2]

The front elevation of the home is an academic replica of the Petit Trianon at Versailles, designed by Ange-Jacques Gabriel in 1761 for Louis XV. It features a balustraded parapet atop the second floor, over a classical entablature with bracketed cornice, plain frieze, and banded architrave. It is composed of five equal bays separated by four Corinthian columns. The columns have traditional Corinthian capitals, slender fluted shafts two stories high, and attic bases resting upon smooth-faced plinths.[2]

The monumental sandstone terraced entrance features white marble steps and landings rising to a pair of symmetric curving stairs which arrive at a broad marble terrace, which is the main entrance to the building. There are four cast iron light standards, each about nine feet tall, which feature lavender glass spheres on top and clusters of four dolphins at the base.[2]

There are regularly spaced French windows at both floors. The first floor has pairs of ten-light casements below an eight-light transom. The upper floor has pairs of eight-light casements. The third floor has a flat roof, painted cement plaster exterior walls, and irregularly spaced double hung windows.[2]

The east elevation has the same parapet and entablature. It is divided into five bays, with four Corinthian pilasters similar in detail to the front columns. It is here that the basement level can be seen. It is surfaced in heavily rusticated sandstone with deep-set openings for double hung windows, secured behind tubular wrought iron grilles.[2]

Between the four pilasters are three large art glass windows designed by artisan and poet Bruce Porter, who was born in 1865. The middle window bears the greeting Salve (Welcome) and the date MCMIV. The flanking windows are images of female-headed terns. There are three smaller art glass windows at the third level, and all are executed in a palette of pink, purple, green, yellow, and blue.[2]

The rear elevation, which is also framed with the parapet, entablature, and rusticated base, has no pilasters or columns. It has unevenly spaced openings, all glazed with the same window type as the front. There is also a small sandstone stair that leads from the garden level to the first floor in one continuous rise. There is one small unglazed opening on the second floor which opens onto a porch, and there is a large fireplace stack centered on the east one-half of this elevation and extending above the parapet.[2]

The west elevation has irregularly spaced openings, reflecting the plan functions within. It, too, has a large fireplace stack extending above the parapet. It features a cast iron and glass enclosed entrance porch.[2]

Much of the cornice and all four front columns collapsed in the San Francisco earthquake of 1906, but were replaced soon thereafter.[2]

The interiors of 3800 Washington feature many notable rooms.[2]

Foyer. The foyer is a small rotunda with white marble floors and dark green marble walls. It is flanked on either side by a pair of small conservatories, each accessed by three pair of curved French doors. Each conservatory has a large stone planter.[2]

The Atrium. This room was designed to bring light into the center of the house. An opening roughly eighteen feet on each side penetrates the two uppermost floors of the building and is capped by a skylight. At the first floor, the atrium features eight green Irish marble columns with bronze capitals and bases.[2]

The Salon. The original decor (no longer existent) of this room was said to have been imported in its entirety from an 18th century French chateau. The room features a 12-foot-high white marble fireplace with a rose marble inset. The room is paneled in a light, soft wood which appears to have been sandblasted. There are large wooden columns, pediments, and cornices and a plaster barrel vaulted ceiling.[2]

The Library. This room was designed to conceal books behind a system of large wooden panels which are detailed with concealed hardware. The panels are flanked by large wooden columns, and all of the woodwork was originally a dark mahogany. There is an elaborately coffered ceiling and rust-colored marble fireplace.[2]

The Dining Room. This room was also paneled in two dark-colored woods and originally featured accents of gold-tooled green leather. The leather has been removed. There is a beamed ceiling with gothic detailing and an enormous fireplace with dark green marble facing and a wooden mantel supported by two nearly life-size carved figures of Bacchus.[2]

The Ballroom. In the basement, there is a large hall of mirrors which runs the entire width of the house. Each wall features panels of mirrors framed by elaborate gilded boiserie. There are raised platforms at each end which were designed to be used as stages for musical performances. The finishes in this room were restored to their original character in 1982, although the original silvering on the mirrors remains.[2]

Second Floor Living Room. The second largest room in the house, it originally featured a dark wooden wainscot and beamed ceiling. It, too, has a large fireplace, this one in tan stone with an arched opening.[2]