jamhead's french drain project

[jamhead]

If interested, you can follow this link to view photos of our french/trench drain project.

When you get to the link, click on the last photo and hit previous to see the project unfold in the correct chronological order. The project was a monster that included 12 tons of gravel; more than that of clay; digging bent over on one knee; pvc pipe-work; and digging on my stomach in the crawl space down to the footer.

The bottom line is that we received over 3 inches of rain in a four hour period yesterday......water is still trickling out of the drain outlet, and the crawl space, to date, is dry.

I hope to never do another project like this....much work, much effort, considerable money, and when completed, cannot tell anything was done.
http://s920.photobucket.com/albums/ad49/jamhead1/French Drain Project/

 

[Zing]

I hope to never do another project like this....much work, much effort, considerable money, and when completed, cannot tell anything was done.

Yes you can...

...the crawl space, to date, is dry.

EXCELLENT WORK! I'm sure this is quite the load of your shoulders.

 

[Srvy]

Nice thats some ball busting work but just think how much you saved. I need to do this myself and I think my drain tiles are all pluged up now the house was built in 1956.

 

[jamhead]

Thanks guys. Yeah, it does feel good as my crawl space is big....1600sq ft and I can actually walk around in most of it. So, I wanted to use it for storage, thus, need it dry.

Part B of this project was to rip out the old moisture barrier on the dirt floor of the crawl, which was 4mil plastic. Then, I made an insect/termite repellent / "bug killer" at work (we have access to great stuff that you cannot buy in the US) and sprayed the foundation walls inside the crawl. I dehumidified for a week to dry out the insect spray and dirt, then....my wife and I laid two layers of 10mil polyethylene sheeting along the floor and used construction adhesive to attach the sheeting to the foundation walls. Taped the seams with sheathing tape, so it's pretty much air tight (adhesive didn't work as planned...as it didn't hold the plastic very well against the foundation).

Running dehumidifier now to keep moisture <60% during the summer and have it draining out to the outlet drain (could see it in one of the photos) out to the creek behind our house.

Also, had an electrician put in 3 - 4ft shop lights in the crawl and 5 outlets. So now, when entering the crawl, flick the switch...and viola....light. We're storing everything in tupperware containers in the event we do have wetness....

 

[-B-]

Just looking at that hurts! Reminds me of digging a hole for a trench well at Batmans first house. Moving earth is hard.

Question, when finishing basements etc I was always told make nothing air tight to avoid moisture build up on the other side. I see you did so and was curious if that was the recommend way. I know this type of are would be different than a standard basement. I'd still be cautious and store in plastic bins or on pallets.

 

[Doghart]

Nice work man, my back aches just looking at it.

D

 

[jamhead]

Thanks guys.

B:

It's definitely not air tight. The plastic only runs up the walls of the foundation about 6 inches. My goal was to make it as close as possible to air tight with the soil. The crawl is vented (closed during summer with dehumidification) but will be open the remaining 8 months of the year. The walls are not insulated, so no moisture barrier there.....

If I were to condition the crawl, then I would need to insulate walls; moisture barrier; and then make it air tight. So, the crawl is ventilated, just an air tight seal over the dirt.

And yes, most of the important things (memorabilia is being stored in plastic bins...shrink-wrapped around the seal of the lid). But, the humidity level is currently 58% (much less than an attic and not enough to cause mold growth....humidity over 60% continually). My wood moisture content is 12% (anything less than 20% is safe from mold....30% is where decay begins.)

Answer your question, or did I not understand?

Oh, and total cost of french/trench drain: $1300.

Total cost of french drain; outlet drain from crawl space to creek, electrical work in crawl, moisture barrier in crawl: $2500.

Best quote for french drain: $4000
Best quote for all: $6000

And, with me doing the work...I used solid PVC instead of the flex tubing, which allowed me to install 2 cleanouts in the event dirt/roots plug up the pipe in the future. Flex pipe is a "one and done'....so if clogged, re-do drain.

 

[-B-]

Thanks guys.

B:

It's definitely not air tight. The plastic only runs up the walls of the foundation about 6 inches. My goal was to make it as close as possible to air tight with the soil. The crawl is vented (closed during summer with dehumidification) but will be open the remaining 8 months of the year. The walls are not insulated, so no moisture barrier there.....

If I were to condition the crawl, then I would need to insulate walls; moisture barrier; and then make it air tight. So, the crawl is ventilated, just an air tight seal over the dirt.

And yes, most of the important things (memorabilia is being stored in plastic bins...shrink-wrapped around the seal of the lid). But, the humidity level is currently 58% (much less than an attic and not enough to cause mold growth....humidity over 60% continually). My wood moisture content is 12% (anything less than 20% is safe from mold....30% is where decay begins.)

Answer your question, or did I not understand?

Oh, and total cost of french/trench drain: $1300.

Total cost of french drain; outlet drain from crawl space to creek, electrical work in crawl, moisture barrier in crawl: $2500.

Best quote for french drain: $4000
Best quote for all: $6000

And, with me doing the work...I used solid PVC instead of the flex tubing, which allowed me to install 2 cleanouts in the event dirt/roots plug up the pipe in the future. Flex pipe is a "one and done'....so if clogged, re-do drain.

I guess my main question is the air tight seal for protection on the top side and the underside still able to vent elsewhere? If not would that create some type of potential problem of any sort.

 

[jamhead]

Sorry B, not sure what you mean by top side and underside. I might be a little dense today..so please be patient.

 

[jamhead]

Here...do these photos of the crawl space help?

 

[Rope]

First and third shots look like a piller section of a mine when they were still using continuous miners.

I'm miffed that city or county code would allow pillers for load bearing.

Utah requires footers with a load bearing wall, much like the third picture, on the right.

Rope

 

[heeman]

Great Job Jamhead!

Piece of mind is worth all of that labor!