How to add drainage to concrete patio?

1. Dig a trench around the perimeter of the patio and make sure it is at least 6 inches deep.
2. Line the trench with gravel or crushed rock, allowing for 3-4 inches of space from the top of the trench.
3. Lay down a layer of landscape fabric to keep any soil from clogging up the drainage.
4. Place perforated drainage pipe in the trench and connect it to a drain outlet or other drainage system.
5. Cover the pipe with gravel or crushed rock, making sure there is enough space for water to travel freely.
6. Re-pour the concrete patio, making sure to create a slight slope away from the house so that rainwater can drain.
7. Place the final layer of gravel or crushed rock on top of the newly poured concrete, adding more if needed.