BTW, I'm in the middle of this project now, got all of the trenching done yesterday (oh, btw, propane lines are only buried 12 inches deep for those of you in rural areas, trenchers go through them quite quickly).

Looks like for my house, the project will be about $250 including the trencher. I'm using this COEX stuff, which is a 3 inch pipe that's like PVC only a bit cheaper, specifically designed for drain systems. For about the same cost you can get it in rolls, but I did it in the white 10 foot sections. Home Depot carries all of this stuff.

Everything is in the ground now, just need to work on the "leveling to make sure we're draining from high to low.

So, if you guys find this in a search result, let me know and I'll tell you how it turned out.

KD

I'm planning to put in a new drain system for my downspouts. I'm considering the 10-foot lengths of 4-inch COEX at Home Depot, but have some questions about using it that you can probably answer.

1. Is the COEX flexible enough to allow some curvature in the trenches?

2. Did you use any of the white styrene fittings (elbows, tees, y's, etc.) that Home Depot seems to sell for COEX?

3. If you used any of the fittings, what kind of cement did you use?

4. How did your project turn out?

Thanks.

I used the 3 inch 10 foot sections, non perforated, at least I think it's 3 inch, it's smaller than the 4 inch sch 40, and it worked well.

1. I think yes, my trenches weren't totally straight, and I was able to bend it a bit to make it fit. You can also bend a bit at the connections. It is rigid pipe, however, so if you have a lot of turns, the flexible black rolls would work better, and they are basically the same price after all the fittings, etc.

2. Yes, I used elbows, t's, and couplers, and they worked great, perfect fit, just make sure you get the ones in that section at HD.

3. I used PVC primer and glue for those, but may have been better off with just using silicone, the pvc primer and glue doesn't seem to work as well on the coex.

4. The project worked out great. My biggest issue was trying to bring the exit pipe out at grade level and maintaining a slope for the runoff, but i managed to get it to work well. The pipe is only like 4-5 inches deep on the last 20 feet or so, but I can work that out. the other option is to do a drywell, but that's a big hole and a lot of work.

Feel free to email me if you have other questions. info@y4hdesigns.com

KD

Has anyone had to run a 4" drainage pipe under a sidewalk and through a concrete curb. I was told I could rent a concrete drill to go through the curb. What would be best for excavating under the sidewalk? Also, how did your jobs turn out. Any pointers would be appreciated.

I had to go under my sidewalk, and it's not a big deal. I used a regular shovel, but a straight, short one would be easier. Just dig from one side, then the other.

As far as the curb, I'm assuming it's not city property (ie: part of the easement.) if it is, you'll probably need permission to do it, and honestly, I think I'd hire someone (concrete core company) to do it for you. you can find them in the yellow pages.

Without knowing more about your job, I can't accurately comment. Do you have a pic you can post or email.

As far as how it turned out? Great, it's working exactly as I intended, and I'm way glad I did it. The smaller cheaper pipe from HD worked fine (see above).

KD

Dont believe that about gluing pvc with silicone. You must have glue and primer to create the solvent weld, the fusion of elements, silicone will not hold, the pipe will leak and is prone to pulling apart.

That's true for PVC. One thing to remember, though, is that PVC primer and glue don't work on COEX, at least the stuff I used, the outer shell of the coex doesn't respond to the primer, or the glue.

KD

sounds like you got something else, I use foam core on remodel jobs all the time with no problems. not sure whats going on

This is a specific type of material. The brand stamped on it is COEX. I like it because it was cheap and had preformed couplers on on end. It's black on the inside and white on the outside and has sort of ridges on it. It worked really well, and since it's for drainage, you don't have to worry about it really holding a bunch of water and linking, it's just a pathway, at least in my set up, so the couplers do their job.

KD

The problem with leaks on underground gutter drains,(depending on where they are routed,) is that it will create a sink hole, the idea is to get the water away from the house with no leaks. One of my customers had that corrugated drain pipe installed. It leaked under ground and caused the retaining wall to slide down the hill. Dont be fooled, Over time the leak adds up to alot of water, Drains are supposed to be sized for the 100 year storm, which equals 4.75 inches per hour of rainfall. If drains are not sized this way and the 100 year storm rolls around,(or something close) your drains wont handle it.

I hear ya.

Luckily, in my system, other than where the gutters hook in, the joints are all at least 10' from the house. The joints where the 90 degree is at the bottom of the gutter connection are very tight, and everything is draining down hill.

I do see your point, though, and that's why I did a pretty good job ensuring the system has a lot of grade, and the connections are as tight as I could get them.

would the joints be watertight under a pressure test?

Need some help. I need a solution to divert water away from my garage. My problem is I have a walkway just a few feet away from my downspout. When it rains the water collects at the walkway. Is there a solution to remedy this without digging underneath my walkway? I have heavy clay soil filled with rocks so digging is very difficult. I noticed many of my neighbors extend their downspout to their driveway or walkway and let it drain there. My concern about this solution is that it creates a slippery area during the winter months. I suppose I could deal with it draining to the walkway, but wouldn't this increase the likelyhood of the walkway cracking or slanting over time? I live in Minnesota and have to deal with freezing and thaw cycles. Any ideas appreciated. Thanks.

My solution was to dig drainage lines to get it way away from the house. In your case, I think the easiest way would be to get some of that flexible gutter downspout material (the green stuff with ridges that collapse/expand) and connect a couple of them to reroute the water away, possibly running it down the walkway until it's a better place to come out.

It's hard to say without knowing what it looks like, any pics you can post or send?

Thanks.

KD

KD,

I ended up laying about 120 feet of 4-inch COEX to carry away my downspout water. I used the universal (red can) cement for the fittings and it worked well on those joints that fit fairly tight. I used a few splice fittings, which tended to be sloppy, but I relieved some of the stress on them by wrapping them with Pasco 10-mil PVC pipe wrap tape.

When this house was built, the contractor ran the downspouts into 4-inch corrugated about 18 inches deep. The property slopes front-to-back, so the corrugated runs to the back of the house, where amazingly, the runs from the two sides of the house were connected together via about a 40-foot run of 4-inch perforated corrugated. This was right against the foundation, such that water would bubble up out of the ground along the foundation in the backyard. I unhooked the perforated run at each end and connected the two side runs to my new COEX line. I also have some Multi-Flow lines that I'm draing into this new COEX pipe. So far this winter, I'm high and dry.

Thanks for responding to my questions last summer.

I've been reading up on these type of drainage systems and had a question. I'll be burying a line to discharge into a swell at our property line.

How best do I determine what type of piping to use? It sounds like there is corrugated, COEX, SDR-35, and PVC? I plan on using 4" non-perforated but don't know which type of material to use?

Thougths?

I just used the coex. It has fittings built in on the one end, and since it isn't pressurized, seems to work for my application. No issues as of yet with it. I think it's 3". we've had some serious rains, and it didn't overflow.

I thought I'd post a quick follow up to this thread. After 6 seasons (wow, can't believe it's been that long), i'm doing a landscape rework, and started taking a little bit harder look at the drain pipe setup. I can tell in some areas, I have some leakage issues with the coex.

I think if I had it to do over again, going with full on 4-6" PVC would be a better choice for these drains. My area is relatively dry, so we don't get big heavy rain, so 4" will suffice, but 6" would be better if you live in a rainier area.

I'm going to be replacing most of the coex pipe with PVC so that I can better seal it, and just inspecting and suring up the other joints.

If you're doing this for the first time, my suggestion would be to stick with real PVC instead. It'll cost a little more, but long term, it's better.