Drainage Suggestions

[JB4310]

DON'T put your down spouts and foundation drain in the same pipe. You are asking for trouble. Keep them separate.

Good advise,
To Bolster the point, here's a direct quote from a proposal I just wrote this past week for a condo association.

• Alternative, would be to install gravity drains in each of the window wells, tied into the existing underground roof leader drainage system. This approach would not allow for a written guarantee and in fact could potentially cause even more flooding than previously occurred in basement. If the existing underground storm drainage system backed up, caused by excess runoff from the roofs and parking areas, water would flow in reverse and surge into the window wells.

All parties need to be aware of this, as contractor assumes no liability for such an incidence. Storm drainage system backups are a common occurrence and as such we would not recommend this approach due to the increased flood risk exposure.

Ideally basement drainage systems are kept isolated from all other storm water drainage systems, due to the threat of storm water backup as mentioned above.
Cost, $

End qoute

I gave them this option cause that's how another contractor bid the job and they wanted my price to do the same way.​

This same contractor did another units window wells the same way and it it failed twice so far, each time he did additional work, he charged them for it :confused2:​

I normally do what I call a window well overflow drain that ties into the existing interior sub-floor footing pipe. It's the only time we intentionally direct exterior water to the inside, but in most cases it is the only option. We give a written guarantee and never had one fail.​

JB.​

 

[LoveTheSmellofDiesel]

Looks like you are doing a great job and learning along the way.

My only question is, is that perforated pipe set lower the lower level slab, all around the perimeter, especially in the back?
can't tell by the pics
I usually comment on drainage threads, cause I do that type of work, but I must of missed yours.

Cool looking house

JB.

Thanks JB, it is all below the slab with possibly the slight exception of around the corner in the back, the concrete contractor dumped some concrete overpour globs in that area so the last 2 feet by the wall, I've got it at about a 25 degree downslope below the cedar, but possible at same level of slab. I was thinking I should dig it out and get it all to the same level with a slight downward pitch before I cover it all with gravel. I decided I would leave a 3-4' gravel surround around the entire box sticking out vs mulch or some other solution. Curious, even with just a pad on pea gravel then compacted sand what is the recommended depth for the perforated pipe... Since my GC said it was unnecessary due to there not being a basement/crawl, I figured as long as it was below the pad itself we'd be good to go. Thanks.

 

[LoveTheSmellofDiesel]

Good advise,
If the existing underground storm drainage system backed up, caused by excess runoff from the roofs and parking areas, water would flow in reverse and surge into the window wells.

Now that would be the a bad irrigation system! Knowing some, they may just ask to throw a check valve in under the window sill in you pitcure..
We had another downpour yesterday and I can certainly attest if it was configured as your client asked I would have gotten back pressure into the drain tile... As is, I've still got to take care of outlet downstream grade, I had the drain tile outlet fill with dirty water and fill with mud at the end. The 4" PVC pipe outlet worked great again so I'm done with that with the exception of backfill.

 

[JB4310]

Thanks JB, it is all below the slab with possibly the slight exception of around the corner in the back, the concrete contractor dumped some concrete overpour globs in that area so the last 2 feet by the wall, I've got it at about a 25 degree downslope below the cedar, but possible at same level of slab. I was thinking I should dig it out and get it all to the same level with a slight downward pitch before I cover it all with gravel. I decided I would leave a 3-4' gravel surround around the entire box sticking out vs mulch or some other solution. Curious, even with just a pad on pea gravel then compacted sand what is the recommended depth for the perforated pipe... Since my GC said it was unnecessary due to there not being a basement/crawl, I figured as long as it was below the pad itself we'd be good to go. Thanks.

If you mean the pad that makes up the lower level floor which is below grade?

Then Ideally the the top of the pipe would be lower than the bottom of the slab. but it's critical that there is nowhere the bottom of the pipe is higher than the top of the slab, especially along the the discharge route. you might get away with it being higher in one spot as long as the rest was lower in the other direction and the water could discharge in that direction.

JB