My house is about a hundred years old. I replaced the roof and gutters about eight months ago.
When it rains very heavily, we get some water in the basement, in three tiny streams from three of the corners to the central drain. I have had several contractors over to make recommendations and have come to realize, they are (obviously) sales people interested (of course) in selling their own product. I have no idea what to believe concerning what is actually needed and actually best given what I'm seeing.
All these contractors recommended internal drainage, because that's what they sell. I'm reading in some places online that I should first make sure the grading on my yard is good, as well as the length of the drain pipes on my roof gutter system.
Lengthening drain pipes was easy of course. I'm now looking at the slope on my yard.
In general, over the yard as a whole, the grading is good--in general, everything slopes away from the house. BUT in many places right up against the house, there is basically a downslope towards the house. As in, just a foot or so right next to the house has, not as deep as a "trench", but just a slight downward slope toward the house.
So what I'd love to hear, is that can just dig up the plantlife (grass etc) right there at the wall, and get clay soil and basically pour a small layer of it all around the house, pack that in, then replant over it. Basically "patching" the grade so to speak.
Is it plausible that this would actually have a net positive effect on how much water gets down into the soil around the foundation, large enough to make the procedure worth it?
On one side of my house I just have like four feet of yard before it hits a fence dividing my yard from my neighbor's yard. That side of the house also is where the worst basement moisture problems happen. It also is a bit of a jungle so needs considerable clearing before I can be sure what the soil grade is like over there. But I am assuming that once I clear it, if it needs regrading whether as I've described above or more majorly, it will not be cool to just have all the water flow into my neighbor's yard. What do people do in cases like this? Is it plausibly DIY for someone who hasn't really done anything like this before? Or do I need to hire somebody? If the latter, how do I know whether they're doing what's actually needed and best and not just trying to sell me whatever it is they typically try to sell people?
I don't believe I'll be able to actually waterproof the foundation externally as I'm not convinced it's safe to do that kind of large scale soil shifting given the age of the home and the fact that the foundation does already have horizontal cracking and slight bowing on the three walls where moisture does get in.
Similarly, if I'm understanding right, any substantial external drainage system would involve something similarly invasive happening so I'm not so sure whether it's a good idea.
But all thoughts about this are welcome.
Including some pictures from all around the house below.