These stairs that lead to the ceiling are just one of the many
bizarre features that Mrs. Winchester designed and had built.

Prior to the 1906 earthquake, the house had been built up to seven stories tall, but today the highest point is the fourth floor. The house is predominantly made of redwood frame construction, with a floating foundation that is believed to have saved the estate from total collapse in both the 1906 earthquake and the 1989 Loma Prieta earthquake. There are about 160 rooms, including 40 bedrooms and two ballrooms. The house also has 47 fireplaces, 10,000 window panes, 17 chimneys (with evidence of two others), two basements and three elevators. Winchester's property was some 162 acres (650,000 m²) at one time, but now the estate is just 4.5 acres (24,000 m²) — the minimum necessary to contain the house and nearby outbuildings. It has gold and silver chandeliers and inlaid parquet floors and trim. There are doors and stairways that lead nowhere and a vast array of colors and materials. Before the availability of elevators, special "easy riser" stairways were installed to allow Winchester access to every part of the mansion, to accommodate her severe arthritis. Roughly 20,000 gallons (76,000 liters) of paint were required to paint the house. Due to the sheer size of the house, by the time every section of the house was painted, the workers had to start repainting again.

The house also has many conveniences that were rarely found at the time of its construction, including steam and forced-air heating, modern indoor toilets and plumbing, push-button gas lights, a hot shower from indoor plumbing and even three elevators, including one with the only horizontal hydraulic elevator piston in the United States.

Today the home is owned by Winchester Investments LLC and it retains unique touches that reflect Winchester's beliefs and her reported preoccupation with warding off malevolent spirits. The number thirteen and spider web motifs, which she considered to be lucky, reappear around the house. For example, an expensive imported chandelier that originally had 12 candle-holders was altered to accommodate 13 candles, wall clothes hooks are in multiples of 13, and a spider web-patterned Tiffany window contains 13 colored stones. In tribute, the house's current groundskeepers have created a topiary tree shaped like the number 13. Also, every Friday the 13th the large bell on the property is rung 13 times at 1 p.m. in tribute to Sarah Winchester.

She also had 13 palm trees set on opposite sides of the front walkway, six on one side and seven on the other. As the development of the city of San Jose encroached on the property, these trees were moved back, closer to the house — in the same pattern, but closer together. One of the thirteen trees did not survive the replanting and remains only as a dead trunk.

Today, several different tours of the house are available, including flashlight tours at night on dates around Halloween and each Friday the 13th.