The flat patio problem
A patio poured flat, or sloped the wrong way, does two things you will not forgive. It holds meltwater against your foundation and siding, which is the expensive failure. And it turns into a sheet of ice at the back door every night the temperature drops, which is the dangerous one. Both are decided in the hour the forms are set and neither can be fixed afterwards without breaking the slab out — you cannot re-slope cured concrete. A smooth trowel finish makes it worse by being the slickest surface available exactly where people step out in winter.



