U.S. CitiesCity-Data Forum Index
Go Back   City-Data Forum > General Forums > House
 [Register]
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
View detailed profile (Advanced) or search
site with Google Custom Search

Search Forums  (Advanced)
 
 
Old 03-14-2011, 12:58 AM
 
7 posts, read 68,512 times
Reputation: 17

Advertisements

I live in a pretty dry climate (San Diego). I have owned my home for 10 years. The house sits on the side of a hill with a gradual slope. The house is a raised foundation with 2 feet of space in the front and 4 feet in the back. The house was built in 1952.

I have been noticing over the years that my crawl space is very wet/muddy for parts of the year. There are mineral deposits on the perimiter wall and on top of the soil. It is not uncommom to find the soil extremely muddy at times.

This moisture is taking its toll on the house. No mold yet but corroded pipes and rotting wood and termites. The termites have been taken care of fyi. I have been researching options to mitigate the problem. I talked to my next door neighbor and he has the exact same problem. The street in front of our house which is at higher elevation has a drain coming out of the ground. After a rainstorm water flows out of the ground for weeks. Even when it doesn't rain for months water trickles out of the ground 365 days a year. I suspect there is an underground spring or we have a high water table.

Digging in front of the house and redirecting the water is not really an option. Do I lay plastic sheeting? Do I put in a sump pump? Thoughts?
Rate this post positively Quick reply to this message

 
Old 03-14-2011, 06:43 AM
 
1,402 posts, read 3,361,269 times
Reputation: 1312
What kind of ventilation do you have in the crawlspace?
Rate this post positively Quick reply to this message
 
Old 03-14-2011, 11:21 AM
 
Location: Atlanta, GA
1,123 posts, read 6,256,312 times
Reputation: 564
Do you have any type of perimeter drain or sump pump in the crawl? Also, I would recommend covering the entire dirt crawl with at least 6mil plastic (1 foot overlap at seams...taped if you have the patience and time). Moisture in the crawl space is a nightmare and can wreck havoc on your structure. I actually had mine encapsulated, where they seal off all the vents, use 20mil plastic which runs up to within 1' of the top of the foundation wall and up every support pier, all covering a perimeter drain which flows to a sump pump with back up power supply. This is all topped off with a big dehumidifier to maintain 40-50% humidity. I live in southeast, so our outside humidity is out of control, hence the closign of the vents...I don't think this would be necessary in San Diego. I had this all professionally done and it cost a lot of money, but I had beginning mold growth and cupping hardwoods which necessitated the expense and it's been well worth it for me.
Rate this post positively Quick reply to this message
 
Old 03-14-2011, 01:11 PM
 
Location: Austin, TX
16,791 posts, read 46,088,695 times
Reputation: 9456
I'd start by installing a perimeter drain along the uphill side of the foundation, to catch any ground water and divert it around to the two sides away from the foundation. I did this once on a fire station that had foundation movement problems from the soil shrinking and swelling with each rain storm. Worked well.
Rate this post positively Quick reply to this message
 
Old 03-14-2011, 06:10 PM
 
7 posts, read 68,512 times
Reputation: 17
There is no way to put in a perimeter drain because of the concrete in front of the house. My concern about putting plastic down is it will not get rid of the water under the house. I am not comfortable with the idea of my house sitting on a mud foundation. Just for fun I went into the crawlspace today and started digging at the lowest point. The surface was dry but as I began digging it got wetter and wetter. I stopped when my arm couldn't reach further, about 30". The soil is mostly CLAY. No matter how hard I squeeze the clay/soil mixture it does not produce a drop of water.

Will this hole eventually fill with water? Is my only hope to jackhammer the concrete and put a perimiter drain in?
Rate this post positively Quick reply to this message
 
Old 03-14-2011, 06:35 PM
 
1,174 posts, read 6,702,547 times
Reputation: 1096
Quote:
Originally Posted by shuttrbg22 View Post
I have been noticing over the years that my crawl space is very wet/muddy for parts of the year. There are mineral deposits on the perimiter wall and on top of the soil. It is not uncommom to find the soil extremely muddy at times.

The street in front of our house which is at higher elevation has a drain coming out of the ground. After a rainstorm water flows out of the ground for weeks. Even when it doesn't rain for months water trickles out of the ground 365 days a year. I suspect there is an underground spring or we have a high water table.

Do I lay plastic sheeting? Do I put in a sump pump? Thoughts?
Here's my thoughts on the subject.

You live in a dry climate, but it still rains in San diego from time to time. During those rains, the water has to go somewhere and it appears that you're feeling the affect being down hill from the street and on the side of the hill. The water is flowing to you, on or under the ground, as it makes it's way further down the hill.

If you want to keep the vented crawlspace, here's the best thing to do in my opinion. First, you want to install an exterior french drain around the perimeter. Even if it has one, it may be old, crushed, clogged and therefore no longer functional.

It would require excavating down your foundation wall on the exterior, laying drain pipe (the one with holes in it) around the base of the foundation, installing clean crushed rock around the pipe and covering the pipe with drain cloth to keep the dirt out. You do this around the entire foundation and then finally run it out and away from your house far enough away to allow the water to flow away from your house and not soak back into the french drain.

Then, you want to fix or install the waterproofing on the exterior of the foundation wall. There are a variety of ways of doing it, it's just a matter of the money you want to invest to gain the effectiveness you want to obtain.

The second best way to do it would be to put the french drain immediatly on the inside of your foundation. It would be installed similarly to the outside installation, except you wouldn't be covering it with dirt.

You would excavate enough around the inside of the foundation to get the drain pipe (with the holes) beneath the soil level. Then, you would cover it with clean gravel.

The drain would run around the interior perimeter of the foundation to the lowest point in your crawl space where it would either enter a sump pump or gravity drain outside the foundation. Again, the drain pipe, once it exited the foundation, would run downhill as far as possible from the foundation before it let the water out.

If you can run the drain pipe outside without using a sump pump, that's the best thing to do. You don't have to worry about the GFCI plug going off and stopping your sump pump. You also don't ahve to worry about the electricity going out during a storm and again stopping the sump pump. The water will just drain out no matter what if it's a gravity drain system.

If you have to use a sump pump, do it the right way. Don't just dig a hole and put the pump in it. Don't drill a few holes in a 5 gallon Lowes bucket and call it a day. Instead, use the right size sump basin with a lid. They're much bigger that a 5 gallon bucket and go further into the ground. The lid also helps keep any standing water in the basin from evaporating into the crawlspace, especially when used in conjunction with a vapor barrier on the rest of the dirt.

Then, use PVC pipe to evacuate the water. Glue the connections, run it up the foundation wall and olut the siding. Run the pipe back down the exterior of the foundation and into a drain pipe routed far away from the house.

The problem with not excavating outside of the foundation will be the continuing weeping on the foundation walls. It's the effuescence that you're seeing. To deal with that issue, you can cover the walls with plastic sheeting, or a bumpy thicker plastic panel that will allow the water to flow into the interior french drain but keep it from adding to the moisture inside the crawl space.

The thing to keep in mind is to not insall it all the way to the sill plate. Keep it a few inches or so, maybe 6", beneath the will plate. It will allow you to see any termite tubes reaching your wood structure. You wouldn't see them if the plastic sent all the way to the wood.

No matter if you choose an exterior or interior french drain, you'll also want to cover the dirt inside the crawl space with plastic. 6mm thick would be the minimum. It helps keep down the evaporation that will always happen with exposed dirt.

Your other option is the encapsulated (closed crawl space) that was already mentioned. It also involves the installation of an interior perimeter french drain and a sump pump. However, they also use a dehumidifier inside the crawl space since it's not getting any new air circulation. Some even incorporate the newly encapsulated crawl space into the HVAC system so there is a turnover of the air.

That's about all I have to say on the subject for now. My typing fingers are about done. Good luck on whatever you decide to do.

Last edited by garth; 03-14-2011 at 06:50 PM..
Rate this post positively Quick reply to this message
 
Old 03-14-2011, 07:36 PM
 
Location: California
35,412 posts, read 38,981,945 times
Reputation: 32669
We had this problem and ended up installing a french drain system around 3/4 of the house (not the front, just the back and sides) with a sump pump and tied our downspouts into it as well so all the water is collected and disposed of.
Rate this post positively Quick reply to this message
 
Old 03-14-2011, 09:46 PM
 
7 posts, read 68,512 times
Reputation: 17
Thanks for the replies! Me thinks I might install a french drain on the inside perimeter (my back aches just thinking about it). I'm just having trouble picturing this actually collecting water. I can't express how much clay is in the soil ( I could make pottery with it). The water seems to seep so slowly I wonder if this will work.
Rate this post positively Quick reply to this message
 
Old 03-14-2011, 10:16 PM
 
Location: Holly Springs
3,990 posts, read 10,376,874 times
Reputation: 3271
If you notice my signature, I own a company that deals in crawlspace moisture. I am also a licensed building inspector. It sounds as if an interior perimeter drain is your only viable option without breaking the bank due to concrete at the exterior wall. If you take this on yourself, I strongly suggests renting a demolition hammer with a shovel bit for the bulk of the excavation. That will be the best $30-40 you ever spent, I assure you lol. The trench needs to reach the depth of the footer, lay a bed of gravel, lay the perforated pipe with geo-textile sock to keep it from getting clogged, cover the pipe and fill the trench with gravel (#57 washed stone). Put the sump in the lowest corner and discharge to the exterior. It is also a good idea to drill 1/4" holes in the lower course of foundation block to help facilitate the water passing through the blocks.
A vapor barrier, while a good idea to have, will do nothing for this problem so you are correct in that assumption. Feel free to message me and I will be happy to give you all the detailed information you want to take care of it yourself.
Rate this post positively Quick reply to this message
 
Old 03-15-2011, 08:39 AM
QIS
 
920 posts, read 4,838,306 times
Reputation: 574
Hi shuttrbg22,
Can you post a street and city name so we can get an aerial view? You may be sitting on a wet piece of property and and perimeter drain may be an act of futility.
Hi sacredgrooves,
This is your business so please don't take this the wrong way.
Instead of covering the pipe with a sock,try this: when you dig your trench and lay the pipe, lay landscape cloth or the most modern equivalent on the outside of the trench all the way down to the bottom of the trench and lay it over the dirt pile(secure with blocks or whatever),then place the gravel, then fold the cloth back over the gravel and fold or adhere against the foundation or wall and fill the trench. Dirt gets into the gravel easier w/o such protection and will clog the sock! There are already cases when the gravel gets filled and the system breaks down: nobody is happy. Even improperly installed cloth can be an issue.
You are going to "dig" this handbook: Building Envelopes Program Home Pagefoundation/ORNL_CON-295.pdf

If that does not work just google builder's foundation handbook and click on the pdf.

Joe Carmody is brilliant!
Rate this post positively Quick reply to this message
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.

Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.


 
Please update this thread with any new information or opinions. This open thread is still read by thousands of people, so we encourage all additional points of view.

Quick Reply
Message:
Over $104,000 in prizes was already given out to active posters on our forum and additional giveaways are planned!

Go Back   City-Data Forum > General Forums > House
Similar Threads

All times are GMT -6.

© 2005-2022, Advameg, Inc. · Please obey Forum Rules · Terms of Use and Privacy Policy · Bug Bounty

City-Data.com - Contact Us - Archive 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37 - Top