What is emergency roof tarping?
Emergency roof tarping is a temporary cover over a damaged or open section of roof that keeps rain out until permanent repairs can be made. A proper one uses a heavy, UV-resistant tarp large enough to extend well past the damage, carried over the ridge where possible, with its edges wrapped around wood boards that are fastened to the roof so wind cannot get under it.
Marin's storm pattern makes tarps especially useful. Winter systems often arrive one after another, with a day or two of dry weather between them. That is enough time to cover an opening, but rarely enough to finish a permanent repair, rebuild a skylight curb or replace a damaged section of decking. The tarp holds the line until a longer dry stretch.
A tarp is not a repair. It is the step that keeps a roof problem from becoming a ceiling, insulation and flooring problem.
How a professional tarp goes on
- Size it right. The tarp should extend several feet beyond the damaged area on every side, and over the ridge when the damage is near the top, so water cannot run under its uphill edge.
- Batten the edges. The tarp is rolled around lengths of lumber, which are then fastened to the roof. This spreads the hold and stops the edges from flapping.
- Mind the fasteners. Fasteners go through the boards into the deck in areas that will be repaired anyway, not through healthy shingles at random.
- Shed water downhill. The top edge is tucked under shingles or carried over the ridge, so the tarp sheds water like the roof does.
- Flat roofs differ. On low-slope roofs, roofers often use a temporary membrane patch or shape the cover so water does not pond on it.
Plastic sheeting weighted with bricks or tires tends to blow off in the first gust and can drop the weights off the roof. Ropes tied to gutters pull them loose.
When a tarp is needed
- A limb or tree has punctured the roof
- Shingles or a section of roofing blew off and wood is exposed
- A skylight dome or glass is cracked or broken
- A chimney cap or crown has come apart and water is entering
- Water is running through a ceiling and more rain is forecast
- A flat roof section has split or a seam has opened
- Repairs are scheduled but waiting on materials or a dry window
- Moss or debris damage has opened a section that is actively leaking
Why roofs open up in Marin winters
Falling limbs are the most common reason. After days of rain, soaked soil and strong gusts bring down branches from the oaks, eucalyptus and pines that surround many Marin homes, and a heavy limb can break through roofing and decking in one hit.
Wind is the second. Gusts during big winter systems lift and peel shingles, especially at edges, ridges and on exposed hilltop homes, leaving underlayment or bare wood open to the rain that follows.
The third is failure under load. A leak that has been soaking the same spot of decking for weeks can let it soften and give way, and an old skylight dome can crack under a falling branch or simply from age.
What to do inside while you wait
- Put buckets, pots and towels under every drip.
- Move furniture, electronics and rugs out from under the leak.
- Turn off the circuit at the breaker if water is near a light or outlet.
- If a ceiling is bulging with water and there is no light fixture in it, a small hole at the lowest point drains it into a bucket.
- Photograph everything before cleaning up, and keep receipts.
If you can safely get into the attic, a plastic sheet or bin under the drip there catches water before it reaches the ceiling. Step only on the framing, never between joists.
Getting ready before the storm season
The best time to think about tarping is before you need it. If your roof is older, has a known weak spot or sits under large trees, note the roof type, the rough age of the last reroof and where the attic access is, and keep that list with your insurance papers. A roofer who knows those details on the phone can bring the right materials on the first trip.
It also helps to know where your main breaker panel is and how to reach the attic hatch safely, and to keep a few buckets, towels and a flashlight where you can find them in a power outage. Winter storms in Marin can knock out power at the same time they open a roof, so plan for working by flashlight.
What the roofer does on an emergency call
- Questions by phone. Where the water is, what caused it and whether anything is unsafe.
- Safety look. On site, the roofer checks whether the roof can be walked and whether a tree service is needed first.
- Photos. Damage is photographed before it is covered.
- Cover. The tarp or temporary patch goes on, battened and fastened to shed water.
- Inside check. They look at the attic or ceiling to see how far water has spread.
- Next steps. You get a plan for permanent repairs once weather allows.
What shapes a tarping job
| Factor | Effect |
|---|---|
| Size of the opening | Larger damage needs bigger tarps and more battens. |
| Roof pitch and height | Steep and two-story roofs need fall protection. |
| Tree on the roof | Limbs must be removed before covering. |
| Roof type | Tile, shake and flat roofs need different methods. |
| Weather at the time | High wind or lightning means waiting or working from inside. |
After the tarp goes on
Check the tarp after every storm, from the ground, for tears, flapping edges or water pooling on top. Keep the photos and receipts with your claim paperwork, and book the permanent repair for the first reliable dry stretch. In Marin, the dry days between winter systems can be short, so it helps to have the scope agreed in advance.
If the permanent repair turns into a larger reroof, ask whether your address is in a mapped fire hazard area. Larger reroofs there generally have to meet Class A, which affects the materials the roofer orders.
Safety first
Emergency tarping is roof work in bad weather, which is when most falls happen. Do not attempt it yourself during wind or rain, and never on steep, mossy or two-story roofs.
Stay off wet, steep or windy roofs, and tarp from inside the attic where possible. If water is near a light fixture, switch that circuit off at the breaker. Keep everyone out from under a sagging ceiling, and if a tree has hit the house or it looks unsafe, get out and call 911.
Emergency tarping questions
How long can a roof tarp stay on?
A well-fastened tarp is a temporary fix meant to last until a dry window for repairs, usually days to a few weeks. Sun and wind wear tarps out, so they should be checked after every storm and replaced if torn.
Can a tarp go on while it is still raining?
Roofers sometimes cover openings in light rain when it is safe, but they will not work in high wind, lightning or on very steep wet roofs. In the worst conditions, the work is done from inside or waits for a break.
Should the tarp be nailed through my shingles?
Professionals wrap the tarp edges around boards and fasten the boards, keeping fasteners in areas that will be repaired anyway or close to the ridge. Random nails through good shingles create new leaks.
What can I do inside while I wait?
Catch water with buckets, move valuables, lay down towels, and if a ceiling bulges with water away from any light fixture, a small hole at its lowest point lets it drain into a bucket instead of collapsing.
Does a tarp work on a flat roof?
Flat roofs are harder to tarp because water pools on top. Roofers often use a temporary patch or membrane over the opening instead, or slope the cover so water runs off.
Will insurance cover emergency tarping?
Many policies expect you to take reasonable steps to prevent further damage, and tarping is a common example. Keep receipts and photos and check your own policy.
Related pages
If a limb or wind caused the opening, the storm and tree damage page covers the repair and the claim. Petaluma's older roofs see their share of winter emergencies, as the Petaluma page notes, and so do the older streets of San Rafael.
Once the tarp is on, use the Rainline Marin leak checker to understand what likely failed.