Pipe and Stone: Old Technology and why it shouldn't be used for Interior Basement Waterproofing Drainage

As I’ve addressed in other posts there are many ways that basement-waterproofing systems can fail.

The General Problem with Pipe and Stone:
Pipe and Stone drainage systems fail because the technology doesn’t allow for specific things to happen. Pipe, PVC, iron or steel, copper or some other material tends to work best for plumbing. Plumbing requires a unidirectional liquid flow with rigid containment. This is so you get water coming out your sink tap and not onto your floor.

What were the advantages:
A Pipe allows for a great deal of liquid volume to rush through. The larger the pipe diameter, the larger the volume of water you can move. This is the theory in using it for basement waterproofing, transitioning from the original French drain tile or Roman stone channel. Companies would then bore holes into the sides of the pipes, typically ¼-1/2 inch in diameter. The pipe was then installed near the footer, seldom pitched to maintain directional flow, and surrounded with stones of various sizes to keep the pipe in place. Early designs left the stone open to the basement interior, to allow surface or wall water and leaks to seep through the stone to the pipe.

The original use of pipe and stone systems left gaps between the pipes in hopes of “generally” get the water flowing in the right direction. However, because water can’t think logically and “follow dotted lines” it jumps the gaps and finds its way back into the basement.

The next incarnation of pipe and stone connected the pipes, but because iron pipe elbows were awkward, seldom fit, and could shift easily, pipe were laid end to end in hopes, again, that the water would find the other drain.

1970 was upon us and other systems came around to bump the pipe and stone system slowly out of popularity.

The Problems with Pipe and Stone:

Back fill: With pipe and stone’s entry holes into the pipe you don’t have many options of backfill. Stone is typically it. However, with today’s companies, some are installing pipe and stone and using sand and dirt to back fill, and hold the pipe in place. Soil and sand allow for shifting and very easily can clog holes of ¼ - ½ inch in diameter. Drilled holes in the pipe make it easy for debris and for clay style soils to get caught and slowly clog the drain by blocking holes.

Curve: The logic is by using a curved pipe the water has less to stick too because a curve helps to reduce the amount of friction the liquid has to overcome in order to flow. By having a low point in a pipe and stone being the bottom of the pipe, the dirt and soil that does come in with the water will slowly settle to the bottom of the pipe. As the area inside the pipe diminishes, it covers the holes that allow the pipe to drain water and allow water to flow through the pipe. Eventual clogs can occur.

Mineral deposits: The standard modern pipe and stone is ether iron or a perforated black piping. The iron pipes can rust and possibly (this is in theory) increase the amount of food for iron bacteria to grow colonies. Iron bacteria can easily clog pipes and cause major problems through a waterproofing system. The perforated black pipe (which you can see at Home Depot in the plumbing isle) has little ridges which just help to speed up the sediment settling process which I just mentioned will clog a drain over time.

Corner Seepage: Most companies, even today, neglect to install corner connections on the pipes (called elbows) which still lead to 85% of pipe and stone system failures occurring in the corners of the basement.

With all the choices today for interior basement waterproofing pipe and stone technology is best to be left outside. It’s the perfect technology for large volumes (pipes being over a foot in diameter, public works, road drainage) where it can be publicly maintained by the town/city/state but for a homeowner it’s not the solution for your basement.

Related Reading and Links

Read about the Top 6 Basement Mistakes that contractors and homeowners make.

Ask Jacob A question Directly on Pioneer Basement's Help Forums!

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