How to Fix a Sagging Roof

Aug 16, 2019

Not all roof problems are noticeable to the naked eye. So when you look at your house and see a sagging roof, it’s probably a bit more than concerning! 

Why Roofs Start Sagging

It’s important to understand why your roof is sagging before you try and fix it. There are a few possible reasons and each reason will have a different solution. The most common reasons why homeowners have sagging roofs include:

  • Too much weight on the roof
  • Bad construction
  • Old roof
  • Damage or rot
  • Standing water or ice

Fixing a Sagging Roof

First and foremost, you should never climb onto a sagging roof on your own, especially without any safety equipment. If your roof has started to sag, it means there is definitely some type of damage that needs to be fixed. However, once you get on your roof, it can be harder to see what type of damage it is right away and you risk falling through your roof. It is always recommended to call a professional to inspect your roof if you suspect there is any type of damage.

Older roofs or water damage

Old roofs that are due for a replacement are more susceptible to getting water damage, especially during the rainier seasons. If water gets underneath your roofing shingles, the plywood underneath the shingles can get rotted or warped from water damage. In this case, your problem is less likely to be framing issues and the best thing you can do is to get a roof replacement.

Heavy loads

Sagging roofs can be caused when there’s too much weight for your roof to handle. Standing water, ice dams, and the accumulation of debris are common reasons for heavy loads on top of a roof. Another possible reason your roof could have too much weight is if new shingles were installed on top of an old roof. However, this is less likely as most local laws do not allow more than one or two layers of shingles on a roof.

The best way to prevent a sagging roof from too much weight is by regularly maintaining your roof. This includes blowing away debris from your roof and trimming back overhanging trees. You may want to consider scheduling annual roof maintenance around the tail end of Fall or Spring. This is when roofs are more likely to have leaves, branches, and debris.

And although we don’t get much snow or ice in Portland or Vancouver, you can also schedule roof maintenance to get snow or ice removed from your roof if it becomes a problem. Standing water from melting snow and ice can definitely add a lot of weight to your roof during severe weather storms and potentially cause structural damage. 

Bad Construction

Unfortunately, it’s not uncommon for roofs to be installed improperly. One of the ways you can tell is when your roof starts to sag soon after roof work is completed. If your roof has been recently built or repaired and has started to sag, it’s structurally unstable. For you and your family’s safety, it’s crucial to get it fixed right away.

There are several reasons why your roof is sagging if it’s been improperly installed. It’s possible the roof joints and rafters were improperly constructed. Or perhaps the rafter ties weren’t nailed properly to the rafters. It could also be because the beams and struts were the wrong size or defective. The only way to know for sure is by calling your local roofer. Ask them to inspect your roof to see if there are other symptoms that indicate what the problem may be. From there, you can figure out what part of your roof needs to be fixed so your sagging roof becomes structurally sound again.

Call IBEX Roof for an Inspection

If you’ve noticed your roof sagging or looking uneven, give IBEX Roof a call at 360-836-0535 or fill out our online form to get a free estimate on your next roofing project. Once we can get eyes on your roof, we will let you know the best way to move forward. Don’t wait to get a sagging roof inspected, as the problem can only get worse over time!