The principle
Ice holds to the roofing like glue. Getting it off by force means striking it, and the blow travels through the ice.
Steam works differently. Aimed through a wand, it melts the ice along a line and cuts it bit by bit. We use steam for roof de-icing, on sloped roofs as well as flat roofs.
Steam is not a jet of hot water under high pressure. A powerful jet can strip the granules off shingles and push water under the roofing.
How we work
The steps vary with the roof, but the order generally stays the same.
- We secure the ground. The area where ice and water will fall is closed off before we start.
- We clear the snow around the ice to see where it starts and ends.
- We open channels. On an ice dam, channels cut with steam let the trapped water drain away.
- We cut the ice into pieces and remove them, instead of melting everything in place.
- We clear the gutters, downspouts or drain so the next meltwater has a way out.
Meanwhile, you stay inside or well away from the base of the walls. Do not go up to look, and do not hold a ladder.
What we avoid
- Picks, axes and hammers. A frozen shingle can snap, and a flat roof membrane can be punctured without the hole showing.
- Salt and de-icers. They can attack the metal on the roof, stain the roofing and burn plants at the foot of the wall.
- Open flame. A torch near a wooden roof edge is a fire risk.
- High-pressure water jets. They can strip granules off shingles and push water under the roofing.
What steam does not do
Steam removes the ice that is there. It does not prevent the next ice.
If an ice dam forms again every winter, the cause is generally heat escaping from the house through the attic. That subject is covered elsewhere on the site, with insulation and ventilation.
What to ask us
Ask us these questions. They apply to any contractor.
- Do you work with steam, or with a pressurized hot water jet?
- How do you protect people, cars and plants at the foot of the wall?
- Can you show proof of insurance?
- What do you do with the ice once it comes loose?
Frequently asked questions
Does steam damage shingles or the membrane?
Generally no, when steam is used properly. It melts the ice without striking the frozen roofing. The risk comes from a wand held too long in one spot or a machine that sprays pressurized water instead of steam.
Can I rent a machine and do it myself?
No, we advise against it. You would have to go up on an icy roof or work from a ladder, under blocks of ice coming loose. The danger comes first from where you would have to stand.
How long does steam de-icing take?
The time for steam de-icing depends on the amount of ice and access to the roof, and it cannot be estimated without seeing the roof. Describe what you see from the ground in your request, and keep photos for the visit.