Metal Roof vs. Shingle Roof: How Each Handles Mountain Snow
Metal roofs dump snow; shingle roofs hold it. Each comes with its own risks and its own rules for safe snow removal.
Published
Walk through any Summit County neighborhood in January and you’ll see two kinds of roofs: metal roofs with bare patches and big piles of snow at the bottom, and shingle roofs still wearing a thick white blanket. Both are dealing with the same storms, with snowfall averaging about 268 inches a year here, but they handle it very differently. Understanding how metal roof snow behaves compared with snow on shingles helps you know what to watch for and how the snow should be removed.
Metal roofs: snow that leaves all at once
Metal roofing is smooth. Once the snow on it starts to warm, from sun or from heat escaping the house, it can let go and slide off in large slabs. That has some advantages and some serious downsides.
The upside
- Snow often doesn’t sit on the roof as long, which can mean less weight over time.
- Metal doesn’t have granules to strip or shingles to crack.
The risks
- Sudden slides. A slab of snow and ice coming off a metal roof can land with real force on entries, walkways, decks, cars, and anyone underneath.
- Overloaded decks and lower roofs. All that snow lands somewhere. Decks often aren’t designed for the loads roofs are, and a single slide can dump a dense pile onto one. See deck snow removal.
- It doesn’t always slide. Snow can stay put in cold weather, in valleys, behind chimneys, and on lower-pitch sections. Ice can still build at the eaves.
- Surface damage. Metal tools and aggressive scraping can scratch coatings, dent panels, and damage seams and fasteners.
Snow guards on metal roofs
Some metal roofs have snow guards or snow retention systems meant to hold snow in place so it melts off gradually instead of sliding. Whether they make sense, and where, depends on the roof and what’s below it. That’s a question for a roofing professional.
Shingle roofs: snow that stays and builds
Asphalt shingles have a textured surface that grips snow. Instead of sliding, snow usually stays on the roof, storm after storm, until it melts or someone removes it.
The risks
- Accumulating weight. Each storm adds another layer. Thawing followed by refreezing adds weight and creates ice, so the load gets denser through the season.
- Ice dams. Snow that stays on the roof is constantly available to melt from underneath and refreeze at the eaves. Ice dams are a particular problem on shingle roofs, because water backing up behind the dam can work under overlapping shingles. See ice dam removal.
- Damage from removal. Cold shingles can be brittle. Scraping down hard, chopping at ice, or using metal-edged tools can crack shingles and strip granules.
Warning signs on any roof
Whatever the roof is made of, watch for:
- A roofline or ceiling that looks like it’s sagging
- New cracks in interior walls or ceilings
- Interior doors or windows that suddenly stick
- Leaks or water stains
- Large icicles or thick ice along the eaves
How snow should be removed from each
Metal roofs
- Plan for where the snow will land, and keep people and vehicles clear of the slide zone.
- Use non-metal tools and avoid scraping the panels.
- Pay attention to valleys, the areas behind chimneys and dormers, and lower-pitch sections where snow holds.
- Check decks and lower roofs below for snow that has already come down.
Shingle roofs
- Remove the bulk of the snow without scraping down to the shingles.
- Prioritize valleys, eaves, and lower roofs below taller sections.
- Deal with ice dams by steaming, not chipping.
- Clear more often during heavy cycles, so the load never gets dense and icy.
On either roof, the work is dangerous on a slippery surface at height, which is why most owners hand it to someone with the right equipment. If you want to handle what you can from the ground, our guide to roof rakes vs. professional removal covers where DIY makes sense.
Mixed roofs and larger buildings
Many homes and condo buildings combine roof types and pitches: a metal upper roof over a shingled lower one, or flat sections next to steep ones. Those transitions are where snow from one surface ends up loading another. Property managers dealing with these buildings can read about commercial and HOA roof snow removal.
Getting help
When you request help, mention the roof type, whether it’s metal, shingle, or a mix, so the job can be planned properly. Call or send a request and we’ll connect you with an independent local professional for roof snow removal in Summit County.