I have a basement that is only about an inch or less above the rear patio leading to it. The patio is below grade and its only water escape is a storm sewage drain in the center.
How can I reasonably waterproof my basement? I would like to avoid a step-sized threshold because it would involve stepping over when entering the basement and be an obstacle. If I just put an Azek board 3/4" thick under the door when installing it, will it effectively protect from water getting in? I understand the higher the threshold, the more water is needed in the patio 'pool' for it to flood inside, which becomes a hazard if the drain outside gets clogged. Essentially, any threshold height will start letting water in given enough flooding outside so nothing is 100% safe but I'm wondering if there is a conventional clearance or code requirement for how high above ground outside a (basement) threshold should be.