By then, we knew that in northwest Framingham, "the lack of till and vegetation on the hills creates extreme runoff situations during heavy rains. A lot of these nice houses have multiple sump pumps, perimeter drains (whatever they are!), and specially graded lawns in order to keep their basement dry – and many still end up damp and clammy downstairs."
So, we don't have a wet basement; we have wet bedrooms, instead! The floors are damp all the time, and sometimes the floors are SOAKING WET! (If you leave a plastic box on the floor for a few days, and then sit on the floor where the box was, you'll get wet to the skin - even wearing three layers of clothing!)
Water is attracted to the concrete surface, and will pull itself through small openings, even against the force of gravity. Since our foundation is wet, the water moves up through the concrete and into the house.
The trick is to keep the foundation dry, whether you have a basement or not. You can usually control moisture by having the land sloped away from the house itself,
Installing gutters and drain spouts appropriately, and keeping them clean, and
Keeping flower beds and bushes away from the house.
At our house, the yard is sloping down to the house. The gutters were installed wrong, and they don't work AT ALL. Water pours through them and gushes down every corner, too. And there are very wet flower beds right smack against the foundation all around the house.
Add in the steeply sloped hill in the backyard, the lack of till and consequently sparse vegetation, the unusually high water table, and the soil that is 100% clay, and it is a recipe for disaster.
The location is ideal and the yard is my idea of paradise - but what a helluva mess we're in now!