The feng shui of the guardrail on the second floor of the house belongs to the category of home feng shui. Traditional Feng Shui believes that the design of guardrails on the second floor of a house should comply with the principles of balance of yin and yang and harmony of the five elements to achieve effects such as warding off evil spirits, attracting wealth, and promoting luck. From the perspective of the five elements, wood belongs to the east, fire belongs to the south, earth belongs to the middle, metal belongs to the west, and water belongs to the north. Therefore, if the material and color of the guardrail on the second floor can correspond to the direction of the room and the five elements, it can play a role in warding off evil spirits. For example, wooden guardrails can be used for rooms in the northeast, while gray or yellow earthen guardrails should be used for rooms in the southwest.