Fujian Andesite is a type of natural stone commonly used in construction and landscaping applications. While it is generally a durable and versatile material, whether it can be used for exterior applications in very humid climates largely depends on various factors such as the specific characteristics of the stone, the climate conditions, and the level of maintenance provided.

In general, Andesite is known for its high compressive strength and resistance to weathering, making it suitable for outdoor use. However, its porosity may vary depending on the specific type and quality of Andesite. If the stone has a high porosity, it may absorb moisture from the humid climate and lead to potential issues such as cracks, stains, or degradation over time.

To ensure the suitability of Fujian Andesite for exterior applications in a very humid climate, the following measures can be taken:

1. Sealant: Apply a high-quality sealant specifically designed for natural stone to reduce the stones porosity and enhance its resistance to moisture penetration. The sealant should be applied correctly and reapplied periodically as per manufacturers instructions.

2. Maintenance: Regular cleaning and maintenance are essential to protect the stone from humidity-related problems. This may include removing debris, dirt, and algae growth, as well as cleaning any stains promptly.

3. Proper installation: Ensure that the stone is installed correctly, following appropriate industry standards and best practices. Adequate drainage systems should also be in place to prevent water pooling or accumulation near the stone.

4. Climate considerations: It is essential to consider the specific environmental conditions of the humid climate where the stone will be installed. Factors such as temperature fluctuations, heavy rainfall, and exposure to direct sunlight should be taken into account to determine the stones suitability and ensure proper maintenance practices are implemented.

While Fujian Andesite can potentially be used for exterior applications in very humid climates, it is crucial to consult with a professional stone supplier or installer who can assess the specific characteristics and conditions of the stone and provide appropriate recommendations.