ᐅ Basic Understanding for Installing Splash Protection and a Patio on Clay Soil

Hello everyone,

We are currently in the interior finishing phase of our single-family house without a basement, working with a local company. For accessibility during the waterproofing, the builder dug a trench about 3m (10 feet) wide and approximately 30cm (12 inches) deep around the house. According to the soil report, the soil (clay) has "little to no infiltration possible."

I am planning to install a terrace in the spring, as well as a splash protection strip around the house. If I imagine placing a gravel trench for splash protection around the house or filling the existing trench with gravel, mineral mix, and crushed stone as a base for the terrace: will I be creating something like a bathtub due to the poor infiltration capacity of the soil, causing water to accumulate against the foundation slab/waterproofing layer? Is that unfavorable or does it not matter? Do I need to plan for drainage?

I hope you understand what I mean—I’m still a complete beginner here...