What are the signs a roof is overloaded with snow?
The Department of Energy's Building America Solution Center lists them, citing FEMA's snow load guide (FEMA P-957):
- A ceiling that sags, or roof trusses whose bottom chords visibly bow
- Creaking or cracking sounds from the roof or a deck
- Doors or windows that will not open or close
- Cracks that open up in wall or ceiling finishes
- Cracks or splits in framing or masonry
None of these is normal winter settling. Each one is the structure telling you the load has gone past what it is comfortable carrying.
Why do doors stick when there is snow on the roof?
Because the framing above them is moving. The same DOE guide lists sticking doors next to a bowing structure and creaking sounds: when the roof and ceiling framing bend under weight, the openings below are pulled out of square, and a door that closed last week binds in its frame.
A door that sticks for other reasons, swelling in humid weather or a loose hinge, does not come with the other signs. A door that starts sticking in the middle of a heavy snow, with new cracks or sounds, is the one to take seriously.
What should you do if you see a warning sign?
Get people out of that part of the building first, then call. The DOE guide, citing FEMA, says to evacuate and contact a qualified professional engineer when these signs appear, and its snow removal advice adds: if the roof is sagging or creaking, get down immediately.
Do not go up to shovel it. OSHA's hazard alert says a roof weighed down by snow can collapse under the added weight of workers and their equipment, that falls cause most of the deaths and serious injuries in rooftop snow removal, and that anyone near such a roof should stay alert to unexpected sounds or movement.
Which roofs show strain first?
Roofs that hold snow, and roofs that were already weak. Flat and low slope roofs keep what lands on them, and drifts pile against walls, chimneys and higher roofs (flat roof snow guide). The Insurance Institute for Business and Home Safety's figure of about 20 psf for a residential roof assumes the structure is not damaged or decayed, so a roof with old damage or decay may carry less.
OSHA also warns that removing snow unevenly can overload one part of a roof, so a half finished job can be worse than none. How much snow weighs, and how much a roof is built for, is in how much snow a roof can hold.
What happens after the snow is off?
Have the roof checked. Damage under a winter of snow is hard to see from the ground, and a leak that started under an ice dam can keep going after the snow melts.
Rocket Roofing General Contractor offers roof snow removal and steams ice dams, and the roof check after a storm is free: we look at the roof, the gutters and the siding in one visit, photograph what we find and put it in writing with a free estimate. Book a free assessment, or call us at (402) 291-8888.
Can melting snow overload a roof too?
Yes. OSHA's hazard alert warns that surfaces weighed down by snow, or by the water from melted snow, can collapse, and that anyone near them should stay alert to unexpected sounds or movement. Water that cannot drain, behind an ice dam or on a flat roof with buried drains, weighs more than the snow it came from, inch for inch.
That is why the warning signs can appear during a thaw rather than a storm. A ceiling that starts to sag on a mild afternoon after a heavy snow is a sign to act on, not a sign the danger has passed.
What should you not do when a roof shows strain?
- Do not climb up to relieve it. OSHA says a roof weighed down by snow can collapse under the added weight of workers and their equipment, and the Department of Energy's guide says to get down immediately if a roof is sagging or creaking.
- Do not shovel one side. OSHA warns that removing snow unevenly, or piling it on the roof, loads one part of the roof more than the rest.
- Do not stand under it. Keep people out of the rooms under the strain and away from the eaves outside.
- Do not wait for it to get worse. The DOE guide, citing FEMA, says to contact a qualified engineer when the signs appear.
Who checks the framing, and who checks the roof?
A structural question belongs to a structural engineer: the Department of Energy's guide says to contact a qualified professional engineer when the warning signs appear, because the framing, not the shingles, is what is under strain. Once the snow is off and the structure is safe, Rocket Roofing General Contractor checks what the winter did to the roof itself, the shingles, the flashing, the gutters and the decking we can see, and puts it in writing with photos.
Is a roof damaged by snow covered by insurance?
Generally, yes. Triple-I says a standard policy covers damage when the weight of snow or ice damages the house, though policies vary and yours decides. Photograph the sagging, the cracks and anything that leaked, with the date, before anything is moved or repaired, and keep receipts. The ice dam insurance guide explains what to ask your agent.
Who is Rocket Roofing General Contractor?
Rocket Roofing General Contractor has served Omaha, Papillion and the rest of Nebraska since 2008. We are registered with the Nebraska Department of Labor, NE DOL #98741-26, and we are a GAF Certified Residential Roofing Contractor. Our crews physically clear snow and ice from roofs and steam ice dams. Headquarters: 5634 S 85th Cir Ste 204, Omaha, NE 68127. Call us at (402) 291-8888.