I just had an roof constractor give me a multi-thousand dollar estimate
for installing heating cables along the edges of the roof (about 300').

Then I looked online and saw DIY heating cables selling for about
$1/foot. This seems to be a big price difference. Where is the extra
cost (10x) coming from? Is there a significant difference between a
DIY kit and the equipment a "professional" would install? Is it all
labour? Or am I being taken for a ride?

Thanks

Dave I


louie wrote:
Two things combine to cause ice formation on roofs:

1. heat loss
2. inadequate ventilation

The window may not be enough ventilation for your roof. Ideally, you
would want ridge and soffit vents to allow the air to flow up the
inside of the roof surface. You may also want to look at how much
insulation you have in your ceiling and see if you can improve that as
well.

A short term fix could be to add heating wires along the first couple
of feet of roof near the bottom and plug in the heaters whenever you
see ice building up to dangerous levels. It's a little wasteful, but
maybe less expensive in the short term and I've seen people use this
method effectively to prevent ice-dams from forming and backing water
up on the roof.