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What Causes a Sagging Roof?

Sagging roof

A brand new roof should be completely level, with flat, straight surfaces to allow debris and water to run off with ease. As your roof ages, however, a few factors can contribute to roof sagging. While a small amount of sagging isn’t necessarily cause for an emergency, it does mean you need to act quickly to get the problem repaired before the structure of your home is compromised.

Whether you need a sagging roof repair or a full roof replacement depends on the cause and extent of your roof damage. Here are 4 of the most common reasons for a sagging roof, but keep in mind it’s always best to consult a professional to identify the exact issue and learn the best steps to correct it as quickly as possible.

4 Possible Causes Behind Your Sagging Roof

1. Water Damage

Your roof is continually exposed to wind, rain, and snow. Over time, these elements are capable of causing a great deal of water damage to your roof, especially if your roof is poorly maintained. Since roofs deal with a lot of run-off throughout the year, it’s crucial as a homeowner to pay attention to how rain and snowmelt drain off your roof. Imperfections in your roof surface, poorly designed gutters, and damaged shingles can all lead to water damage and eventually to a sagging roof. 

Taking good care of your roof can help prevent this problem, but keep in mind that any type of damage to the surface of your roof opens the way for water to get in and weaken the overall structure of your roof. It only takes a small amount of time for trapped moisture to create an environment for mold and mildew growth, easily developing into a sagging roof and even a roof collapse. If this is the case, consult a professional for a roofing inspection and a sagging roof repair.

2. Excess Weight

If you live in an area that gets snow or ice in the colder months, keep in mind that this can add a lot of weight to your roof. While your roof should be designed to withstand a certain amount of weight, too much weight can lead to a sagging roof, a roof collapse, and other serious structural damage to your home.

If you’re noticing your roof is sagging under snow, or if you’re expecting a larger amount of snow than usual, you should find a way to safely remove as much excess snow as you can from your roof to help reduce the load. Be careful with snow rakes so as not to break any frozen shingles, and know you can always hire a licensed roofing contractor if you need help with snow or ice removal.

3. Bad Materials or Poor Installation

If your roof has been constructed using subpar materials or installed by an unskilled roofer, it’s possible to face issues of a sagging roof much sooner than expected. If the roof joints or rafters are poorly installed and constructed, your roof can end up sagging under its own weight. 

4. Age

Even if your roof was installed by the most skilled of roofers using the best materials on the market, it will not last forever. Roofs can last between 15 and 70 years depending on the materials used, the design of the roof, and the surrounding climate. If you look at your roof and think, “My roof is sagging,” it could simply be due to age. If your roof is over 30 years old, getting a full roof replacement rather than a sagging roof repair may be the most efficient way to resolve the issue.

How to Repair a Sagging Roof

If you understand the cause of your sagging roof, you are much better prepared to resolve the issue. However, it’s also important to identify the extent of the damage so you know if a repair or replacement is more appropriate.

  • Do an outside examination of the roof and determine where in the attic you can best view the sag.
  • Take a flashlight and go up into the attic to inspect the rafters nearest where the roof is sagging. Also inspect any of the metal or plywood gusset plates.
  • Check for any and all signs of damage, including rot or mold, cracking, breaking, etc.

Document any damages to help determine the extent of the damage. Some problems behind a sagging roof can be resolved by jacking up loose rafters, adding struts and supports, and replacing shingles, but some problems will require help from a professional roofer. 

Repairing a sagging roof

Don’t attempt to fix your sagging roof yourself if you aren’t a skilled professional. Call an experienced roofing expert for a proper inspection and to get an accurate quote for sagging roof repair costs.

Replace Your Sagging Roof Today

In many cases, a sagging roof repair isn’t as effective as a full roof replacement—which Long Roofing makes more affordable through our flexible financing options. If you notice that your roof is sagging, call 866-270-7058 or contact the Long team online to request an estimate for your roof replacement.

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