Is it acceptable for trim to slope towards the house?

The notion that trim should not slope toward the house is grounded in fundamental principles of water management and building envelope performance. When trim slopes toward the house, it creates a pathway for water to flow toward and potentially enter the structure. This situation can lead to issues such as water infiltration, which may result in damage to the building's interior or structural elements, mold growth, and other water-related problems.

In contrast, ensuring that trim slopes away from the house promotes proper drainage, allowing any water that collects on the trim to drain away from the building. This practice helps maintain the integrity of both the trim and the underlying structures by minimizing moisture exposure and enhancing the overall durability of the building envelope.

While there may be some design aesthetics or climate considerations that can influence specific approaches, the primary concern remains the protection of the home from water intrusion, making the practice of sloping trim away from the structure the best guideline for most situations.