In message , Steve -
www.ukspeedtraps.co.uk writes
"Janet Baraclough" wrote in message
...
The message
from "icarus" contains these words:

Hi folk,

I have two greenhouses that are covered in algae and dirt at my new
house.
Is a pressure washer going to be too harsh to clean the glass ?

Anyone with experience please ?

Some older GH's have the cheapest quality horticultural glass which
breaks easily under pressure stress; or pops out of those old-style
clips. Newer, better quality GH's may have been fitted with stronger
glass, or even safety glass on the walls and ends, each pane held
securely all the way round with a rubber seal against the frame.

That's a good point Janet, I should have said that all my glass toughened
4mm and stuck in place, if it was not TSG and stuck I would not use a
pressure washer on it. It would not be safe in my opinion.

I've used a PW on two GH, both probably 20 + years old, standard cheap
horti glass, never had any problem with glass breakage, nor would I
imagine it's very likely. The little metal clips can sometime get pinged
out though, but easy to replace. Much the best way for cleaning along
the edge, in the channels etc, and the overlaps between glass.

I would wear some eye protection though, not for the glass but because
of bits of detritus that can get wash out. I find a visor type one much
more comfortable and easy to use that glasses/goggles.
--
Chris French and Helen Johnson, Leeds
urg Suppliers and References FAQ:
http://www.familyfrench.co.uk/garden/urgfaq/index.html