OK, Texas! Ice Dams! These are going to cause a lot of problems.
Ice dams are caused by temperatures in the attic being warmer than the roof, by radiant heat from the sun, or by temperatures that fluctuate. There’s not a lot you can do to stop the sun, there’s not a whole lot you can do right now about poorly insulated attics, and (sadly) there’s not a lot of solutions for an ice dam that has already formed, but here are some tips.
Right Now:
Take photos! Document for potential insurance claims. THIS APPLIES TO FROZEN PIPES AS WELL! Double check your insurance and see what kind of damages are covered. Most policies will cover water damages from leaking but if you end up with standing water, that is considered flooding and is separate coverage. If you are sheltering away from home and suspect frozen pipes, call your utility company and get that water turned off ASAP! If you rent, your renters insurance covers personal property only; your landlord’s dwelling policy covers the building. If you know you need coverage you don’t have, see if you can add it and pay the difference to make it retroactive to the start of the policy. (Not every company will do this, but it’s often cheaper to pay the premium difference + deductible than to fix the damages out of pocket.)
Try to stop any active leak. Take a fan into the attic and aim it at the underside of the roof where water is actively leaking in. You are hoping to re-freeze the leaking water to stop the leak. Even if the attic air is above freezing, the blowing air and exterior temperatures can combine to refreeze thin layers of water.
Try to cool your attic. If you have gable vents you can try using a fan to vent attic air faster, but unless you can cool the attic to below freezing you are unlikely to make a large difference in ice dam formation.
Be careful with large icicles. Icicles are a sign of water melting and then re-freezing, so if you have large ones you probably have an ice dam. If you have gutters you are even more likely to have an ice dam. Falling chunks of ice are unpredictable. Leave them be, but keep an eye on them. Keep pets and children from playing under them.
You can knock off smaller icicles. Just knock them away using a large pole or rake handle. Then move them away from the walkway as melting and refreezing will cause slippery patches.
Rake off the edges of your roof. There aren’t a lot of snow rakes in these here parts, but gently using a leaf rake to remove the top layers of snow will help open up the eave so the sun can have an easier time melting down to the shingle. Do not scrape on your shingles as this will cause damage by removing granules.
DO NOT USE A HAMMER ON THE ICE DAM! Or a chisel or shovel. It can cause damage to your shingles, drip edge, gutters, and possibly decking. If conditions are right it can cause large sheets of ice to slide off the roof (onto you!)
Calcium chloride ice melter. Be aware that salt will kill any plants under the eave of the house and you don’t want to salt your fields; avoid rock/driveway salt for deicing a roof. Fill the leg of discarded pair of panty hose, lay the hose onto the roof so it crosses the ice dam and overhangs the gutter. Of all of the solutions available to actually remove the ice dam, this is the only one that people in this area might have. And even then, it’s only those prepared for freak winter weather that have de-icing solution on hand. Calcium chloride is a kind of salt and can also damage plants, so cover shrubs under the area with a tarp.
Prevention for Next Time:
Insulate the attic. This one will help with your summer electric bills too! I know whole-attic insulation can be cost prohibitive, but there are some small steps you can take as the budget allows.
This Old House is an excellent resource for small affordable fixes you can make yourself. Here is their list of tips in order of priority. But remember, every step helps and you can do them in any order you can budget for!
Ventilate Eaves And Ridge. A ridge vent paired with continuous soffit vents circulates cold air under the entire roof. Both ridge and soffit vents should have the same size openings and provide at least 1 square foot of opening for every 300 square feet of attic floor. Place baffles at the eaves to maintain a clear path for the airflow from the soffit vents.
Cap the Hatch. An unsealed attic hatch or whole-house fan is a massive opening for heat to escape. Cover them with weatherstripped caps made from foil-faced foam board held together with aluminum tape.
Exhaust to the Outside. Make sure that the ducts connected to the kitchen, bathroom, and dryer vents all lead outdoors through either the roof or walls, but never through the soffit.
Add Insulation. More insulation on the attic floor keeps the heat where it belongs. To find how much insulation your attic needs, check with your local building department.
Install Sealed Can Lights. Old-style recessed lights give off great plumes of heat and can’t be insulated without creating a fire hazard. Replace them with sealed “IC” fixtures, which can be covered with insulation.
Flash Around Chimneys. Bridge the gap between chimney and house framing with L-shaped steel flashing held in place with unbroken beads of a fire-stop sealant. Using canned spray foam or insulation isn’t fire safe.
Seal and Insulate Ducts. Spread fiber-reinforced mastic on the joints of HVAC ducts and exhaust ducts. Cover them entirely with R-5 or R-6 foil-faced fiberglass.
Caulk Penetrations. Seal around electrical cables and vent pipes with a fire-stop sealant. Also, look for any spots where light shines up from below or the insulation is stained black by the dirt from passing air.
Planning a new roof? Ask about having ice and water shield installed in valleys, around all roof penetrations (like chimneys or vents), over all slopes with a 4/12 pitch or less, and around the perimeter. Some of that (specifically valley and low slope) might be covered by your insurance company if you live in an area with code enforcement. But it does exceed code minimum for most of Texas, so there may be some out of pocket expense. It won’t prevent ice dams, but it does help keep water from getting through the decking in the places it is most likely to build up! You can also plan some of those above ventilation changes (#1, 3, 6, & 8 specifically) as part of the roof work! (Again, there may be out of pocket costs, depending on your insurance policy, roofing company, and your roof situation. Having a roofing company add insulation (#4) might also be cheaper than hiring a company to do it later.)
