Basement water

[PeteV]

Hello everyone, need some suggestions on a problem that I have with water in my basment, I live in a 100+year old farmhouse in NW Ohio and have occasional water seeping up through the basment floor and the bottom of the foundation walls. The walls are made of fieldstone and morter and probably in excess of 18 inches thick. the mortar is very "soft", it is pretty easy to chip away at it.I have 1 basement sump, it does not collect water from the outside. I am pretty sure there is no foundation tile or drains on the outside of the walls. the top of the soil outside is probably 5 ft above the basement floor. I was thinking of digging the dirt away from the basement walls down to under the level of the foundation and installing draintile (properly)Couple of questions. 1. has enyone done this before and how did it work? 2. how far should I go under the foundation level, if any? 3. how far should I stay away from the foundation to prevent setteling or possible collapse of the basement walls during digging?.$ Is it worth the $$ to pressurewash, tar and put up blueboard the basement walls, with walls this thick?4. how wide should the gravelbed be ?
Thanks in advance for your responses
Pete
PS we are sitting on solid clay for a soiltype /forums/images/graemlins/smile.gif

 

[Darren]

I'd look at the sump first. A sump allows a pump to lower the phreatic surface in the vicinity. That's a fancy way of saying water table.

The deeper you can draw down the water table the less chance you have of SUBSURFACE water entering your basement. If the water entering the basement is surface water, that's a different situation. You have to ensure that runoff from the roof is directed far enough from the house so it doesn't seep into the basement and also that the ground slopes away from the house.

If the water is always entering the basement at the base of the masonry wall, I'd look at deepening the sump first. Does the area around the sump remain relatively dry while the wet areas in the basement are the farthest distance from the sump?

Once the sump pump gets the water out of the basement it has to be dumped far enough from the house so it doesn't drain back toward the foundation.

 

[Egon]

I'd sure like to make some comments but in situations as this they are best left to onsite observations by people familiar with the area and the building practices of days gone by.

Egon

 

[Anonymous Poster]

Keeping water out of a basement, while desirable, can often lead to devistating results. In your case, since the building has been there for the period it has, your safest and most cost effective solution is to collect the water at the base of the wall, carry it to a sump, and pump it out.
Youf first consideration, given the stated condition of the mortar, is that gravity is probably the major force holding the walls together. That being the case, you want to keep any intrusion to the wall minimal. You also want to minimize any potential for frost to act against the wall.
The simpl;est and probably best method would be to saw the floor 18" back from the wall, trench appropriately, and install perforated collector pipe and stone, and then restore the floor, leaving a collector trench with small lines (1" pvc) running from the collector to the pipe.

 

[rancar]

Hi Peter....

Your basement sounds just like mine. My home is a 175 year old Greek Revival in upstate New York....built on a fieldstone foundation.....with loose mortar that's crumbling...and water seeping in, primarily in the Spring during snowmelt and heavy Spring rains. I've decided there IS NO feasible, cost-effective way to solve this dilemma without jacking up the house and completly re-building the foundation or replacing it with poured concrete. I was not going to spend $50-75K to do this. I don't use the basement for anything except to store firewood. I also have the hot water heater and well water retaining tank that are on raised platforms. I installed two drainage pipes in the basement floor to catch the waste water. These drains run into a drainage pipe that I installed that runs under one of the foundation walls. This drainage pipe runs on a descending slope away from the house and drains into the lower pasture. This is the only 'inexpensive' way I've figured out to address this problem. It seems to work as the basement seems to dry up by May.

....Bob

 

[Hoeman00]

I had a basement like yours and when I decided to put
on an addition I had to fix old basement too.
Bought 5 40' I beams and ran them crossways under house
put cribbing and jack posts in middle after I used big
hoe to dig overdig around outside.
The addition has a walkout so I could drive in and dig
out old basement w/ SSL(CUT w/FEL would work too).
It took almost all day to do this, I had to drop old floor 3'
to get 9' basement ht.
The outside of these old walls are really rough, if u fix
u have to watch that someone doesn't cave in wall trying
to dig out for footer drains.
U can't put blueboard on these old walls and I don't know
if tar will help because of large gaps in outside of wall.

I wouldn't pay $50-75 k for 1-2 weeks work.

 

[Anonymous Poster]

Pete,

I have the same situation here in MN. House is 100+ years old with 18 inch fieldstone. Our water table is very high where I live (the new 200 foot well was put in just before we bought the place and when the guy came out to cap the old well, he said it only went down 25 feet--not water I would personally drink).

I have resorted to building a false floor and walls about 8 inches away from the original floor and wall. I let the sump pump take the water out and we run a dehumidifier that drains into the sump pump. It works almost non-stop during the summer months.

I would like to do more with the foundation, but like someone else in this post mentioned the cost can be very high and I have been very hesitant to disturb the ground around the foundation. If you come up with a good solution, please let us know--I have a feeling there's a lot of us with these types of basements.

Anyone else out there have this problem? Have you come up with any good, inexpensive solutions?

Bob

 

[Darren]

While such a system isn't feasible for a homeowner, a contractor when installing underground utilities sometimes has to use a wellpoint system to lower the water table. This enables the contractor to literally suck the water out of the ground using as many well points as necessary. The pump has to be operated almost continuously.

Depending on the terrain, a french drain could be installed so it completely surrounds the house and performs the same function. Rather than dig out the fill next to the foundation locate the drain far enough from the house that the excavation doesn't compromise the foundation.

Install the drain so that elevation wise it's below the basement. If the terrain is such that it doesn't allow you to gravity drain through an extension that dumps to a point lower than the basement, a sump could be installed to lift aand dispose of the water.

The terrain could be a problem. If the ground is higher than the house in all directions, the water from the drain has to directed somewhere it can't flow back to the house.

 

[PeteV]

Thank everyone for their response, I am not sure that the current sump is connected to anything but the couple of drains in the floor, iaw I don't think it drains water from the outside. Maybe that would be a good start, to break the concrete bottom out of the sumphole and see what happens.
I don't think that this house is worth the jacking up and do over again procedure, but I admire your attitude. Thanks again everyone, I ll let you know what happens
Pete

 

[RegWaters]

I had a simlar problem but on a newer house . The house was built in 1985 and we bought it in 1987. It is set on a slight but level rise on the property. The basement has poured concrete walls and a floating slab floor and is centered under the house occupying about the center third under the first floor space. The only means of egress is a door leading down from the kitchen. Its like a 20 by 30 foot swimming pool under the house. Luckily it never quit filled that full of water, but in the winter (Jan- feb) we usually get a good 2 week rain. After things start drying up the water table rises about 2" in the basement coming up through the sump and the expansion joints around the base of the wall. The sump was nothing more than a 6" square hole cut through the concrete to the gravel. To alleviate the problem I enlarged the hole to about 1.5' and dug down about 2'. I then inserted a cardbord concrete tube. I shoved 4- 1" pcv pipes about 1'under the slab and into holes cut into the tube. I then backfilled around the outside of the tube with sacrete. After it set up I removed the tube, threw some gravel into the bottom and installed a pedestal sump pump. It now keeps the water pumped out below the slab and the basement stays dry. The only thing I've yet to install is an alarm to let me know when the pump fails.

Good Luck,

Reg in SC