When To Clean
The timing matters more than the frequency. One cleaning at the right moment beats two at the wrong ones.
Short answer
The essential visit is late fall, after the leaves have finished dropping and before the first hard freeze. A spring visit clears what the winter put in and checks for damage. Under mature maples or pines, a mid-fall visit as well, because one late cleaning will not keep up.
The late fall visit
The one that actually matters, because a full trough going into a Toronto winter is what freezes and tears the run off the fascia.
Timed after leaf fall is finished, which in Toronto means late in the season rather than mid-October.
And before the first hard freeze, which is the constraint at the other end.
Downspouts cleared as well as troughs, because the elbow at the top of the downspout is where the blockage usually is.
Outlets and strainers checked.
And the hangers and the slope checked while somebody is up there, because that is free information.
The window is narrow
Between the last leaf and the first freeze is a few weeks in Toronto, and everybody wants it in the same fortnight. Booking it in September for a November date is the practical answer, because calling in December means it does not happen.
The spring visit
Clears what blew in over the winter, which on a windy site is substantial.
Finds the winter damage: pulled hangers, sagging runs, split downspouts, deformed troughs.
Checks the slope, because ice frequently changes it.
Checks the sealant at the joints and the end caps, which freeze-thaw cycling works at.
Clears seed pods and blossom, which in a Toronto spring block a trough as effectively as leaves.
And lets you get the repairs done before the summer storms rather than discovering them during one.
When you need more than two
Mature maples overhanging the roof, which drop enough to fill a trough twice over.
Pines and spruce, which shed needles continuously rather than in a season and which pack into a trough tightly.
A roof with shallow slope or long runs, where debris does not move toward the outlet.
A trough with guards fitted, which still need checking even though they need clearing less.
Granule shedding from an aging asphalt roof, which settles in the trough and holds water.
And after any roof work, because a tear-off puts debris in the trough regardless of how carefully it was done.
Common questions
How often should eavestrough be cleaned in Toronto?
Twice a year as a baseline, and three times under mature maples or pines.
When exactly in the fall?
After the leaves have finished and before the first hard freeze. Book it early.
Do the downspouts need clearing too?
Yes, and the elbow at the top is usually where the blockage is.