Why this usually happens
Leaves and debris buildup — the most common cause. Troughs fill with leaves, seeds, and shingle grit until water has nowhere to go but over the edge.
Clogged downspouts — even clean troughs overflow if the downspout is blocked.
Lost slope — troughs that have sagged or shifted no longer drain toward the downspout.
Damaged or undersized sections — cracks, gaps, or troughs too small for your roof's runoff.
Why you should not ignore it
Overflowing water runs straight down your fascia and soffits and pools against your foundation. Over time that leads to wood rot, peeling paint, basement leaks, foundation cracks, and washed-out landscaping. A routine cleaning costs a fraction of that water damage.
Across Durham Region, eavestrough overflow often shows up during spring thaw, summer storms, and fall leaf drop. Homes in Whitby, Oshawa, Ajax, Pickering, Bowmanville, and surrounding communities can collect leaves, maple keys, roof grit, pine needles, and neighbourhood debris quickly, especially when trees overhang the roofline. When water starts spilling over entrances, gardens, walkways, or foundation walls, it is a practical warning sign that drainage needs attention before the next heavy rainfall.
What to do next
- If you're comfortable on a stable ladder with a spotter, you can clear visible debris by hand — never in wet or windy conditions.
- Test the downspout: run a hose into it; if water backs up, the spout is clogged.
- If troughs overflow even when clean, the slope or sizing may be the issue — that needs a professional look.
- For most homeowners, the safest fix is a professional eavestrough cleaning that clears troughs and downspouts and confirms proper flow.
A safe exterior cleaning approach
Our eavestrough cleaning and brightening service clears your troughs and downspouts, flushes them to confirm flow, and leaves the exterior clean — protecting your home from water damage. We serve Whitby, Oshawa, Ajax, Pickering, Bowmanville, and across Durham Region.
Related DSS services and local pages
Frequently asked questions
How often should eavestroughs be cleaned?
Twice a year — spring and fall — for most homes, and more often if you have overhanging trees.
Can overflowing eavestroughs really damage my foundation?
Yes. Water pooling against the foundation is a leading cause of basement leaks and cracks.
Should I clean them myself?
You can clear visible debris from a stable ladder, but ladder falls are a common injury — many homeowners prefer a pro, especially for two-storey homes.