A patio is a great way to enjoy outdoor time with family and friends. There are many materials you can use to build a patio, such as brick, cobblestone, wood, and concrete. Concrete is an affordable option that can last for decades if it is poured correctly. When pouring a concrete slab against an existing wall, you should install expansion strips between the patio and the wall to protect both structures from temperature changes in the concrete and the ground beneath it. From what I have read, concrete should not directly touch the foundation of your home.
Instead, you should use an expansion joint or something similar that is glued to the house before pouring the concrete against it. When I pour concrete against a house's foundation, I always use an expansion joint. This involves introducing a short piece of reinforcing bar so that its top is level with the concrete. After the surface is set, push the reinforcing bar further into the concrete so that it is well below the surface.