Interior Clay Weep Tiles? What am I looking at?

Not an inspection, but I would highly appreciate anyone who knows what this is. My inspector was really great, but didn’t pick up on this.

My house (purchased a year ago) is in Baltimore County, MD - built in 1959. I know the house inside and out due to the amount of work I’ve put into it, but there is one thing I’ve recently discovered that I cannot figure out.

Under the steps to my basement, and in the garage, I have two holes in the slab (one plugged by coffee can). They lead to clay pipe. It looks to me like it is some sort of interior weep tile system?

I took a few photos of the insides with my phone stuck inside, and they are clearly not used for wastewater of any kind. You can also see the approx length of the pipes / tiles.

Let me also note that - the pipes appear to run in the same direction as the exterior walls ( that is to say they run parallel to exterior walls). I can tell this by the photos I took, and by sticking my hand down and feeling which way they run.

If this is in fact a weep system, where would you all think the water might go? We don’t have a sump, house is on a hill with the front of the house you can only see 1 level above grade, and you can see two above grade in back. I suppose it is possible it could connect to sanitary lines, but I tested this to the best of my ability - ran water and put my ear up to the holes in the slab I’ve shown in pictures, and I can’t hear any sort of trickling of water draining. So, I’m at a loss as to where this all goes as well.

What do you all think?? I would expect there are some old timers out there that have the answer to this one :smiley:

Please see full gallery here :

does not look like an interior basement system from here.

Any idea what it is if it’s not that?

Possible weep system, most are discharged by gravity so it may exit through or under the footing and daylight somewhere downhill. Most basement drains of that age that drained out to the ground surface have been covered up over the years. I would start by assuming the drain tile is about 1-foot below the basement slab, then go outside and mark a line at that same elevation. Start looking for any possible exit points.

In my case, the exit is almost certainly is covered up unless I’m missing something. If it ever drained above ground, I’ll never know. Where I would expect it to drain (going along with your picture) - that area has been paved over (not my me). However, if it isn’t really used much, it might not be so much of a problem. I’ve watched it during / after a hard rain, and I can’t detect any sort of wetness or draining ( probably due to our grade - good drainage, and sandy soil).

As for your assessment of 1-foot below the slab, that seems just about right according to what I see.

I noticed that the previous (and now deceased) owner had filled one of the holes in the slab with nails (which I’ve now removed). Any reason you can think of for that ? Keep critters out (even though it appears all buried?

As far as the holes in the slab go - are these just cleanouts, or what is the purpose (if you have any clue).

Lastly, any sort or advice or knowledge about the system I should know about them that may be not obvious or may be of future use?

Could you think of any reason that this could be anything else other than a weep system?

Thanks !


If there is a floor drain in the basement the drain tiles could discharge into it, see diagram below. The picture shows draining into the sewer system, however most cities will not allow this anymore.

foundation diagram.jpg

The only floor drain is what is an unfinished shower. I went to check that out recently to see if I could find any kind of connection, but I didn’t detect anything other than the trap. I used a plunger push out some water in the trap so I could see more, and I didn’t see anything interesting. So, I’d say it’s probably safe to say they likely drain unconnected to anything, and probably drains as previously discussed.

Nice diagrams by the way, no clue where you find them, but much appreciated :smiley:

As a PE - anything else to know about these, or any advice to be had, other than probably cap them to keep out pests (I did see a spider in one, no clue how it got there). I would doubt any future maintenance or action needed ( as they don’t seem to really carry water from what I can tell - nothing seen during heavy rains).

Thank you very much for your help, has been much appreciated.

They appeared dry in your photos, so that’s a good thing. I would just cap them off for now.

I built houses in the late 1960’s and early 1970’s (72 of them)

In the late 60’s we employed 4 inch x 12 inch vitrified clay tiles for perimeter drains. The tiles were laid in gravel and butted together. Over the butt joints we placed asphalt shingle strips or 15 lb felt strips to cover the gaps.

The tiles were drained into the municipal sewer system.

Your photo indicates the tiles were butted and in very good condition probably due to the fact they are installed on the inside of the home. Most exterior installations have collapsed by now.

I would suggest the owner/builder was being proactive and installed possibly an additional set of weepers on the inside. I am surprised you do not get a sewer smell but there may be a hidden trap before entering the lateral.

Great to hear from someone that actually did this kind of work.

I never considered the possibility of there being a second set on the outside. but it makes sense now that you mention it. Don’t know that I’ll ever see them unless I have some reason to dig deep around the foundation (hopefully that day doesn’t come).

And ya…I saw the same when looking around about weep tiles, seems like the exterior ones don’t really make it between roots and weight and other factors from what I gather.

I smell nothing other than dirt really. Seems like I’ve seen out there that it is possible they just drain downhill and out, and don’t connect to anything at all. Opinion about this?

Since you built some of these houses that have these systems - maybe you can answer a question or two I haven’t gotten responses on yet ----

  1. As far as the holes in the slab/floor go - are these just cleanouts, or what is the purpose?
  2. Any sort or advice or knowledge about the system I should know about that comes to mind?

Thanks !!

A lot of these homes were built by vets. In many cases, the government supplied the money and the vets did a lot of the work themselves.

If the home is near a gully or ravine, I have seen the tiles drain to the great outdoors and no sewer connections were made.

Possibly the holes in the basement floor were made as a rudimentary floor drain. Sometimes we over think things.

Without seeing the home it is difficult to make an educated guess.

Another thread was talking about weep holes in the brick veneer. I do not know exactly when weep holes were deemed important, but I do know in Ontario they were mandatory in the 60’s. Many homes built in the late 40’s and 50’s do not have weep holes.

Try flushing water with a colour dye and look for the exit. If you want some fun, get a couple of welding rods and witch for the line! It has worked for me in the past.

Hope this helps

I had no clue many of them were built by vets. Ya, there could be many purposes for which they were built, I’ll probably have to let the ideas roll around in my head, but as for now, they are probably not much more than a oddity - serving little to no purpose from what I can tell (and taking into consideration the input I’ve gotten).

I’ll give a whack at maybe putting some water down and seeing where it goes, interesting idea.

Thanks very much for your insight!

I concur.
Repaired many clay tile water control systems.