Insulation and Air Sealing
This is the trade most people with ice dams actually need, and the one they do not call. Ice dams are caused by heat escaping into the roof assembly — so the fix is air-sealing the ceiling plane, insulating adequately, and ventilating so the deck stays cold.
- Air sealing comes before adding insulation. Air leakage carries far more heat than conduction through insulation does, so blowing another foot of cellulose over unsealed penetrations is a partial fix at best.
- Look for a contractor who does blower-door testing rather than one who only sells depth. Measuring where the air is going is the difference between fixing the cause and improving the symptom.
- NHSaves is the programme New Hampshire utilities run for residential energy work, and weatherisation incentives have historically been part of it. Worth checking what is current before you commission anything — the terms change.
- Ask about the eaves specifically. That is where insulation is usually thinnest and most often compressed, and it is exactly where the dam forms.
If you re-roof without dealing with this, you will have a new roof and the same ice dams. We would genuinely rather you spent the money in the right order. The ice dam check will tell you which situation you are in.
Who Else Is Involved
Gutter installers
Gutters and metal roofs need coordinating — a sliding snow load will take an ordinary gutter off a fascia. Heavier hangers, correct positioning relative to the eave, and snow retention above anything you want to keep. Worth having the two trades talk rather than sequencing them blindly.
Solar installers
Standing seam is the best roof there is for solar: clamps grip the seams with no penetrations at all. If solar is anywhere in your ten-year plan, mention it before the roof is specified — seam spacing and panel layout can be planned around it.
Masons and chimney contractors
Chimney flashing is where a great many roofs leak, and the flashing is only as good as the masonry it is let into. A crumbling crown or open mortar joints will defeat perfect flashing. If the chimney needs work, do it with the roof rather than after.
Panel suppliers and fabricators
Regional metal roofing suppliers roll-form panels and fabricate trim and accessories. Some sell direct to homeowners as well as to installers, which is worth knowing if you are pricing a barn roof you intend to do yourself.
Roof Raking, Safely
Rake from the ground, with a proper roof rake. Clearing the first few feet above the eave after a heavy fall genuinely reduces dam formation. You are not trying to clear the whole roof; you are removing the fuel closest to the cold edge.
Do not get onto a snow-covered roof. People are seriously injured in this region every winter doing exactly that. A metal roof under snow is as slick as anything you will ever stand on, and a roof that sheds snow will happily shed you.
Never chip at ice with a hammer, shovel or axe. You will damage the roofing, the flashing or yourself, and the ice returns within the week because the cause has not changed.
Watch overhead before you rake. Power service drops frequently run near an eave, and an aluminium roof rake is an excellent conductor. Know where your service entrance is before you start.
On snow load and permits: New Hampshire towns set their own ground snow load requirements for structural design, and they vary by town and elevation. If a project involves structural changes, adding load, or altering how snow leaves a roof over a public way, that is a conversation with your local building department rather than with a website.
What Is Ours, and What Is Not
Ours: standing seam and metal roofing, asphalt-to-metal replacement, asphalt shingle roofing, eave and valley detailing, flashing, snow retention design, and diagnosing whether an ice dam is a roofing problem.
Not ours: air sealing and insulation, gutters, solar, masonry and chimney rebuilding, structural engineering, and anything about what your roof is worth at sale. Where a question belongs to one of those, we will say so rather than stretch.
Six Questions Worth Asking Any Roofer
“How did you calculate the roof area?”
If the answer is the house footprint, the number is low by 6–45% depending on pitch.
“What is the deck repair rate, and when is it agreed?”
Before tear-off. On an older roof something is usually found, and that is the wrong moment to negotiate.
“Is tear-off and disposal a separate line?”
It should be. Folding it invisibly into a per-square-foot figure makes quotes impossible to compare.
“What underlayment, and what ice-and-water detail at the eaves?”
High-temperature synthetic under metal, and membrane where it matters. This is not a place to economise in this climate.
“Where will snow retention go, and why there?”
The answer should reference what is actually under your eaves, not a standard layout.
“Will this fix my ice dams?”
The honest answer is “it will reduce them, and the cause is heat loss.” Anyone who says yes without asking about your attic is selling.