I am about to have a new patio installed and there are two gutter downspouts that will dump onto the patio. I already have a problem with water going into my crawlspace, but it has been suggested that once I put in a patio and slope it away from the house, the water into the crawlspace should stop. Should I have the downspouts run into PVC pipe under the cement? and if so, won't that cause problems later on (clogging, etc.). Please help. I do not want to pay to have this big patio installed and still end up with problems.
I would recommend installing drainage away from the house. Instead of sticking the end of the downspout into the drain line, which makes for extremely difficult maintenance (removal of downspout for cleaning ) Install a debris filter or receptacle box for the downspout to drain into. This will provide a leaf catcher to prevent clogging of the drain and facilitate removal of the downspouts when necessary.
debris filter:
http://www.lawn-care-tips.com/filter.html