Here in my part of VA, we don't install sump pump's if the basement is a walkout, but almost always if the basement is an inground type. The difference being that the walkout will have daylighted foundation drains when it is built. The problem comes in when over the years, or when the home is final graded they fill in or cover up the ends of the pipes. When it is a daylighted foundation, I always try and locate the ends of the pipes for my customer, if I can't I inform them of the importanace of these pipes and that they need to be opened up and kept that way. I built my home and the only time I had any water in my basement was after one of the hurricanes hit my area and sure enough I had not done the very mainatnce that I inform my cutomers of. Tom Barber in VA