Gutter cleaning is the job most worth doing from the ground. It is also the job people most often do from a ladder while holding a running pressure washer, which is a genuinely bad combination. A telescoping wand with a curved end solves it.
How they work
A curved or U-shaped tip on the end of an extension wand hooks over the gutter edge and directs water along the trough. You stand on the ground, extend to the eaves, and flush the debris out along the run and down.
The wands that do this well are telescoping, so they collapse for storage and shorten for the lower sections, and they are rigid enough not to flex wildly when the water hits. The Tool Daily 21-foot wand covers a standard two-story eave and includes a brush head, which is also the right tool for the soffits and fascia while you are there.
What they do well
Loose leaves, grit and shingle granules flush out readily. For routine autumn maintenance this is faster than the ladder-and-bucket approach and considerably safer.
The exterior of the gutter and the fascia, which is where the black streaking shows up. With a house wash and a brush head, that is where the visible improvement comes from.
Confirming a downpipe is flowing without climbing.
What they will not do
Compacted sludge. A gutter that has not been cleared in several years contains a dense mat of decomposed leaves. Water will not move it and you will need hands and a scoop, which means a ladder or a professional.
A blocked downpipe. Flushing from above can pack a blockage tighter. Clear downpipes from the bottom.
Precision. You are working blind at 20 feet. You will not see what you are flushing, and some of it will come out onto you, the wall and the planting below. Dress for it and pre-wet the beds.
Two safety points that still matter
Never spray upward into the eaves or under the shingles. Water driven up under the roof edge goes into the roof structure, and the gutter is not worth that. Direct water along the trough, not up.
Look up before you start. Service drops, cable runs and light fittings are at eave height, and so are wasp nests. A 20-foot metal wand near a service drop is a serious hazard.
More on the handling of long wands in extension wands, and the general rules in safety for beginners.
Check the fitting
These attach to your gun, so the usual question applies: 1/4-inch quick connect or M22 threaded, and if M22, 14mm or 15mm. A cheap adapter set removes the uncertainty — the quick connect guide explains how to tell which you have.