Portugals Rosal T Limestone can be used for exterior applications in rainy climates, although some considerations should be taken into account.

Firstly, its important to note that limestone is a natural stone material and therefore porous. In very rainy climates, the limestone may absorb the water, which could lead to discoloration and potential damage over time. To mitigate this, the limestone can be treated with a water repellent sealant to reduce water absorption and protect it from the effects of moisture.

Additionally, the type of finish and thickness of the limestone can also impact its suitability for exterior use in rainy climates. A more textured finish, such as a honed or brushed surface, may be less slippery when wet compared to a polished finish. Likewise, a thicker slab can provide more durability and resistance against the elements.

Ultimately, consulting with a professional stone supplier or an architect experienced in using limestone in rainy climates would be advisable to ensure the best choice and proper installation for your specific needs.