Here is the front of my house. As you can see it is a 2-story dwelling on the left with a garage on the right that is connected to the main house by a "sunroom" (porch/breezeway/whatever). The main house has a basement, but there is nothing underneath the sunroom or garage.
Here is that sunroom from the back (excuse the mess – still finishing off Fall cleaning):
Where our concrete patio meets the foundation under the sunroom we have a big hole that has opened up (about the size of a golf ball) that you can see in the center of the photo:
And up close:
We've lived in the house for 4 years and this is the first time this has happened. I believe water caused this hole (we live in upstate NY and the cold winters and ice have chipped away at it year after year). The concrete patio was never poured correctly so it slopes (slightly) towards the house, and in the Spring when the snow melts the water funnels towards the house.
Some questions:
- Why is there a big hole there? Shouldn't it all be solid concrete?!?
- If left unattended, what's the worst case scenario here (so I can justify spending money on a solution to my wife)?
- What is the best DIY way to fix patch this hole so we can get through another winter?
- What can I do in the long run so that this doesn't keep happening every year?
Thanks in advance!
Best Answer
This part of the foundation is most likely spreading out a roof load from a sizable portion of the sunroom roof. If the soil supporting the foundation has eroded away, this will need to be rectified some time next year.
For now, get a bag of ready mix mortar, the kind you just add water to, it has sand and cement already mixed in in the correct proportion. Mix up a small amount, keep the water to a minimum so it will stay where you put it and not slump down. Patch the hole. That's all this is right now, a temporary patch.
If the hole opens up beyond such that you feel like it's sort of a bottomless pit, cut a short length of something like a paint stick. Thin enough to push through the hole but long enough to wedge inside when turned 90 degrees. Tie a length of wire to the center so you can keep it pulled tight when you push mortar up against it.
As you suspect, water and freeze/thaw cycles chip away at the foundation over time. There was probably once a innocuous hairline crack there at one point. Water got in there and froze, opening the crack. Repeat dozens of times a winter and over the years you get what you see now.
The solution is keep water away from the foundation. I see you have a gutter system over this area. That is good. The patio sloping towards the house is really bad. Not only does it get into foundation cracks and erode the material, water gets under the house structure and can cause uneven settlement, stressing members in ways that was never intended. Some people think crooked floors in old houses are "charming". In reality it is a sign of an unstable structure. Even if the house stays stable, water can be the source of toxic mold. Water has no place in your house other than inside plumbing.
You need to correct the drainage issue. Ideally, it should slope by gravity away from the house at least with a 2% slope. Another solution, not nearly as good, is to place a sump at the lowest point and pump collected water away. I can't emphasize enough how a natural gravity solution is far superior to a mechanical solution. Sometimes you do what you have to do though.
Combine this with the possibility of needing to correct erosion under the foundation. You my be digging up the patio anyway. OTOH, if the foundation is still properly supported and you correct the drainage issue, your little mortar patch could possibly be considered a permanent fix.