Tom Ireland notes:
have never had any problem with my knees but as soon as I put my knee
down on plywood when roofing or working in a crawlspace I know I need
something. I looked at the knee pads available and I couldn't find what
I
needed. The Tommyco brand ones that they sell here are garbage. I need
a
good pair of leather pads with lots of felt. They run about $16CDN -
$27CDN here but the staps on the back are leather and are not wide
enough
to stop them cutting into the backs of my legs. I am of the opinion
that I
need both the strap on ones until they start cutting into the backs of
my
legs as well as free standing ones that I can kneal on the rest of the
time. I suppost I could wrap my knees with surgical supports the type
they
use for sprained ankles etc with the strap ons. That might help!

Try your Canadian Sears stores. Their GelTek pads are good. I don't
know if Duluth Trading sells in Canada, but their (pricey) top of the
line models are excellent. I've got several kinds (I keep trying, after
knee surgeries that screw up the nerves right where you kneel down).
The Craftsman and the Duluth Trading are the best of the bunch. The
Duluth Trading type has wider straps than the Craftsman, and uses a
Velcro attachment. The GelTeks use two straps with plastic hooks that
fit over knobs on the side of the pads. Both are comfortable on MY
knees, which means they should help almost anyone.