What the heck is a positive drain? Is there such thing as a negative drain?
I did an Internet search on positive drains. I found a lot of information on drainage but not very much on positive drains.
However, if you ask any Nashville homebuilder they will tell you that a positive drain is a necessary and code required component for crawlspaces.
Here’s the idea. Don’t laugh:
If and when water from whatever source gets into your crawlspace, the positive drain is there to allow it to flow out.
Now you might ask the question: Why do I have water in the crawlspace in the first place. I am with you 100%.
We jokingly call them negative drains. Most of the positive drains we see drain the wrong way! Others are the drains to nowhere. The drains are constructed out of cheap corrugated plastic and get covered up when the final grading is done.
Here is what you need to know.
- If you really need a positive drain, you have the wrong homebuilder.
- Ask your builder for a comprehensive storm water management plan.
- Downspouts should connect to underground PVC piping that discharge to a location where water cannot flow back to the foundation or cause erosion.
- There should be a positive grade away from the foundation at all locations. No low spots (bellies) next to the building.
- Do not install drains on the outside or inside of the foundation. Do not let water reach the foundation! No exceptions.
Positive Drain Disasters
DocAir knows how to keep water out of your crawl space or basement. If you would like a free consultation on your new or existing home, please call DocAir at 615-373-2498 or email us at firstname.lastname@example.org.