In order to solve some drainage problems, a designer has proposed the idea of grading up above the level of the foundation. At the highest, the soil would come up to ~3ft over the house band. While he is not sure of the exact structural requirements, he says he has seen this done safely.
I have a stick built house on a block foundation with a crawlspace. It has cedar bat and board siding. The house is on a hill so it acts as a dam to collect water. I have done extensive grading up the slope to divert the water; that has helped a lot. However, nearer to the house I have been limited by the height of the foundation…I just can’t get enough slope coming away from the house to make up for the opposite slope coming towards it….that is without raising the soil level above the house band. A French drain has helped a bit, but it will never be enough to take on the big down pours we get here in the South.
Is this just a plain crazy idea? Is it worth further investigation? Has anyone done something similar? How?
As an aside, I really like the aesthetics of what he has proposed. It would make the entrance to the house much more acceptable and attractive.
Thanks!
Replies
It would be insane to just pile dirt against the house. I imagine redundant waterproofing modifications are made to houses where this has been done successfully. Something like a wood foundation could work if the soil was very stable. I would be inclined to build a retaining wall away from the house to divert the water, if the slope allows that.
It could be done IF (that's a big if) there were a suitable waterproof barrier on the structure, and IF (another big if) the structure is sufficiently reenforced to resist the force of the soil (including frost heave).
Keep in mind that 3 feet requires a substantial retaining wall if you're terracing. Some similar degree of substance is needed in this case.
pile up sandbags and install big sump pump?
If you put dirt up against the wood portion of your house then you too (or some unfortunate future owner) will get to dig it out, repair a mess of rotten bug eaten wood, get rid of the termites, and then install adequate drainage. Ask me how I know this? Hint: I'm the "future" owner.
Remodeling a home built by a crazy man is "interesting."
I agree with the other posters. Not just a bad idea, a stupid idea. Like most such situations, there's not going to be an easy or cheap fix.
A couple of ideas to consider depending on the space you have and how much of the hillside coming down to your house that you own. One would be to build a berm several feet from the house. It would have to be large enough to divert all that water. Make sure that there is a drain line between the berm and the house, as well as on the other side of the berm. Use something like a clay for most of the berm to prevent seepage.
Another idea would be to terrace the hillside using those interlocking landscape blocks. Build several terraces all sloped back toward the hillside, with a large french drain line at the footing of the preceding row of blocks. The idea would be to catch & divert the water before it reaches the level of your yard.
Of course, the other side of that is that it can be done, and done correctly, but will be expensive and a lot of work. You'd have to remove the siding, beef up the framing (with special attention to the sill plate connections), install foundation rated plywood, then install a multi-layer moisture/drainage barrier. Beefing up the foundation might also be necessary. Engineering would be required.
Your aim should be to address the water before it gets to the
foundation. As other's have mentioned, there are multiple ways to do that. While they may not be easy or cheap to install, they may well be cheaper and easier in the long run than repairing damage to the house.
You say that the french drain helps, but doesn't do the job. How was it designed? Is it capturing both surface run-off and shallow ground water that's moving down hill? Proper design of a french drain involves taking the soil conditions, run-off volume, etc. into account.
Your best bet for getting the right solution is to contact an engineer or other professional (maybe a landscape architect) who has the background to properly assess the situation and design the right answer.
Not that hard
But the designer should be capable of detailing what he wants done. If not, he is incompetent. Should no have proposed what he can't do.
OK now down off my high horse shootiong pet peeves
Mark a lkine a foot or so above the new grade.
Take the siding off.
Dig the foundation down to the perimeter drain
use ice a d water shield from tnhe cut siding down to the footing.
Attach expanded metal and apply a stucco
Waterproof that with Thorocoat
Add a drainage membrane - bubble formed with fabric to keep the fines out.
Backfill with stone or inch minus - no clay
Add A Z flashing over top of the dainage mebrane and seal it with vycor.
Re-do the siding
smile, you are done
You forgot to make sure the sheathing is sound enough, and to make sure that the framing is solidly anchored through to the foundation.
I did assume certain things, like the current integrity of the assembly, true.
That would include far more than the couple items you mentioned:
It would involve rebar from footer up through solid cores in the block at least every four feet, preferab;ly at same locations as the anchor bolts, metal wythe in the horizontal mortar joints, good mortar fre of cracks, etc, etc, etc
so easy!
Hey, you make that sound so easy....I guess it is a lot like I thought, maybe building a low block wall to hold the weight, and use the sealing membrane behind it. With all that said, I am still not sure I want to do it (or think about the cost!)
Thanks for all the great input
A curtain drain?
https://www.finehomebuilding.com/how-to/articles/keep-basement-dry-with-a-curtain-drain.aspx