This article is brought to you by AskBobCarr.com — Maryland’s trusted name in foundation moisture control, outdoor drainage, and practical guidance from Bob Carr and the TLC team.
Hi, I’m Bob Carr. And after 35+ years walking thousands of properties in Maryland, I can tell you: if you’ve got water in your basement or crawl space, the first place I’m going is outside.
The number one thing I check first? The downspouts.
It surprises people every time. But more foundation problems start with roof water than any other single cause.
Let me show you why that matters — and what I’m looking for when I check.
Why Downspouts Are So Critical
Your roof sheds a lot of water during a storm — hundreds of gallons per inch of rain. And every drop has to go somewhere.
If that water dumps out 2 feet from your foundation — or worse, flows backward toward the house — it starts soaking the soil. That water pushes against your foundation walls and footers. Over time, it seeps in, builds pressure, and finds a way inside.
Even if your gutters are clean and working, it’s the exit path of the water that makes all the difference.
Think of it this way: A downspout is like a firehose during a storm. Would you aim a firehose at your foundation for hours? Of course not. But that’s what’s happening if your downspouts are dumping too close.
What I Look For First
When I walk a property with foundation moisture, I start with these five downspout checks:
- How many downspouts does the home have?
- Where does each one discharge?
- Are any discharging less than 6 feet from the wall?
- Is the soil sloped away from the exit point?
- Are the lines buried — and if so, where do they end?
I’ll also step back and look for signs like: – Eroded mulch under the eaves – Splash marks on siding – Water-stained block walls – Cracks or efflorescence near corners
These signs tell me water’s been working against the house for a while.
Other diagnostic clues: – Musty odors in the basement after it rains – Paint peeling on lower basement walls – Sump pump running even during dry stretches
Sometimes, a downspout isn’t the main issue. But I start there because it’s the easiest and cheapest fix — and it solves more than people expect.
The Fix That Solves More Than You Think
We solve more water problems with buried downspout extensions than almost any other fix. Here’s what we do: – Dig a trench 10–30 feet long – Use solid pipe (never corrugated) – Maintain 2% slope to the exit point – Discharge to a pop-up, dry well, or daylight
When needed, we also regrade the soil, install a catch basin, or tie into other yard drains.
Why it works: – It gets water away from the foundation – It stops soil saturation that feeds basement leaks – It lowers humidity and moisture readings indoors
Bonus benefit: Many clients report their sump pump barely runs after we redirect the roof runoff.
Real Story: Glen Burnie, MD
A family called because their basement carpet felt damp and the corner walls had peeling paint. A competitor recommended interior drains for $12,000.
We walked the yard and found: – Four downspouts dumping within 4 feet of the house – No slope in the mulch beds – A buried pipe clogged and backing up
Their frustration was real — they had already regraded once, sealed their walls, and tried waterproof paint. Nothing worked.
Our fix: – Cleaned and extended the downspouts 25 feet out – Rerouted one to a daylight slope in the back – Regraded two beds with topsoil and compost
Total cost: Under $3,000
Result: No more dampness. The carpet dried, and the dehumidifier ran less. No interior work needed.
Homeowner reaction: “We wish we’d called you first. We spent two years chasing this when it was all about the roof water.”
When Downspouts Aren’t the Issue
Sometimes, we find the downspouts are already extended — but the problem is elsewhere.
Case in point: A client in Annapolis had a finished basement with one wall that leaked during every storm. The downspouts were buried and 20 feet long. At first glance, everything looked fine.
But when we scoped the line, we found: – The exit was buried under a newly installed deck – The line had crushed under a foot of gravel – Water was backing up right against the wall
Our fix: – Rerouted the buried pipe to a new outlet near a retaining wall – Added a cleanout access point – Installed a catch basin to manage overflow from the patio
Result: The leak stopped. The basement stayed dry. And now the homeowner can flush the line if needed.
The takeaway? Even when the system looks good — you have to test the whole path.
Checklist: How to Inspect Your Own Downspouts After a Storm
Want to take a quick look yourself? Here’s what to check:
- ✅ Are gutters flowing freely?
- ✅ Do all downspouts have an exit path?
- ✅ Are any downspouts draining within 6 feet of the foundation?
- ✅ Do you see splash marks, mulch washout, or erosion below the eaves?
- ✅ Are buried pipes clear and discharging during rain?
- ✅ Is your yard sloped to keep water moving away?
If you answer “no” or “I’m not sure” to any of these, that’s where to start.
Final Thoughts From Bob
If you’ve got foundation moisture — before you think French drains, sump pumps, or waterproof paint — go outside and check your downspouts.
They might not look like much. But they carry more water than anything else around your house. And when that water’s handled right, most moisture problems stop before they start.
Downspouts are the first thing I check — and for good reason. They’re small, simple, and powerful when done right.
📞 Call (410) 721-2342 or schedule your foundation moisture check at AskBobCarr.com
Because big water problems usually start with something small — and we know where to look first.