Thanks to all who made comments on my
problem with green algae growing on the
outside of my vinyl siding and that lower
pressure 'washers' may do the job but
maybe at a slower rate.

I will look into 'siding cleaning' agents
and maybe try them, too. We've had a variety
of experience with fungus (black, rather
than green, smudgyness and dots) and
cleaning that with soap/bleach by hand (not
fun at all).

The warning about water being injected
behind the siding is a valid concern
and I'll have to think about this. I do
know that it is not uncommon for people
to power wash their homes at some interval
and that unwanted side effect is certainly
a possibility. I was present during one
power wash of someone else's house and
water did get injected behind roof flashing
and started drippingfrom an interior room
ceiling.

In the house we owned before the present,
we had the exterior power-washed before
selling the house AND also after the power
wash I replaced some of the siding (cedar)
because of unsightly pre-existing cracks
and/or warps (the moisture barrier was,
believe it or not, roofing felt) and I
noticed no moisture residue or short-term
rot (house & siding were about 20 years old)
and I mention this as an FYI.


Art Sowers
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