If you put off fixing a wobbly fence post or squeaky door hinge, it’s probably not going to end in a homeowners insurance claim. Other home repairs, if left unchecked, can quickly domino into major disasters. Water is a factor—if not the primary cause—in the majority of high-risk situations. Here’s how to identify priority home repairs and handle them at their source:

1. Runaway Rainwater

•Telltale signs: Rain pouring over gutters and puddling along foundation walls.
•Why you need to act: Water can deteriorate siding and foundation walls, eventually finding its way to interior spaces and damaging them.
•What to do: Inspect the entire gutter system for clogs and corrosion; you can clear clogs yourself, but if your gutters are corroded, you’ll want to talk to a pro about having them replaced. Check that the soil around your home’s foundation slopes away from the house at least 1 inch per foot for 6 feet or more. Regrade the soil if the slope is insufficient.

2. Leaky Roofs

•Telltale signs: Cracked, curled, or missing shingles, which signal that the roof is near its end of life; also cracks in the flashing around chimneys, skylights, roof valleys, and the rubber boots around vents.
•Why you need to act: If your roof doesn’t provide a proper barrier to rain and snow, water can find its way to your home’s drywall and insulation, leading to rot and interior water damage.
•What to do: You might be able to replace a shingle here or there or patch leaky flashing. But if your roof is more than 20 years old, it’s probably time for a new one. If it’s an asphalt shingle roof with only one layer, you might be able to add a second layer over it, lowering the project costs significantly. But check the manufacturer’s warranty for the new roofing material to make sure it covers that type of usage, and talk to an experienced contractor or engineer about whether your roof can support the considerable extra weight.

3. Insect Infestations

•Telltale signs: Rotted wood in the sill plate that sits on top of the foundation and cast-off wings along windowsills and walls are evidence of termites. Piles of sawdust along baseboards are a sign of carpenter ants.
•Why you need to act: Tiny as they are, these insects can cause major structural problems if left to nosh on your home’s wooden framework.
•What to do: Call an exterminator. Check for accreditation on the database of the National Pest Management Association.

4. Foundation Cracks

•Telltale signs: Cracks in the concrete, especially those that are wider than 3/16 inch, as well as signs of the walls bulging and buckling.
•Why you need to act: An unstable foundation can compromise the entire structure of your house.
•What to do: Hairline cracks can usually be filled with an epoxy injection system such as Polygem’s Liquid Concrete Repair Kit. If the cracks seem to be getting bigger, you’ll want to get an opinion and next steps from a structural engineer.

5. Mold and Mildew

•Telltale signs: Musty odors, dank air, and black mold spores growing on surfaces such as bathroom ceilings.
•Why you need to act: Any surfaces that harbor extensive mold, including drywall, carpet, and ceiling tiles, will need to be removed. Otherwise mold spores will be released into the air, causing allergic reactions and asthma attacks.
•What to do: If you catch it early, patches of mold less than 10 square feet can be treated with a homemade solution of 1 cup chlorine bleach per gallon of water. Wear an N-95 disposable respirator, goggles, and heavy-duty gloves. For larger outbreaks, or if the ventilation system is contaminated, call in a mold-remediation pro.

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