The Kenai Peninsula received heavy amounts of snow this winter season, which created large amounts of snow on roofs.
With several commercial roof collapses on the Kenai and Anchorage this winter, Kenai Fire Chief Tony Prior explains some recent concerns that were called into the Kenai Fire Department;
“We actually had a call to possible roof collapse and when we went there we we did a check, because the the homeowner said heard some noise and it sounded like something was popping and cracking. And they thought they were having a collapse. And with the snow load that we had, you know after the last dump of snow, they were kind of concerned that maybe what was happening and when we actually arrived on there and got got to look and there was no collapse on there. If you’ve ever lived in a log home when you get those super cold temperatures the logs and the dimensional lumber things that you have start popping and cracking and they make some very loud noise. And sometimes when they do that so, when we get those extreme cold temperatures wood will, it kind of dries out and they start cracking so you get you get a you tend to get some noise coming out of them and that’s what was happening on there. But, we have actually had an an unusual amount of of snow I think back to probably ’94 or so, in those days when we had typical snow dumps like we have this year, and this is a lot more than we’ve had in the previous years.”
Chief Prior discusses how current trusses handle snow loads;
“70 pound snow load for our typical area right here in Kenai/Soldotna area and what that is really is the top cord which is that pit pitched top piece of the the truss system is designed for 60 pounds of snow load and then an extra 10 pounds of dead load. And that dead load means the the plywood and shingles or whatever type of roofing material you have that basically attaches to the top of the truss and then that equals your 70 pounds of load. At the bottom of that cord, which is the horizontal one, that goes from top plate to top plate of your wall is also designed for 10 pounds of load which means your sheetrock or gypsum or tongue and groove or whatever you’re attaching to the bottom part inside your home. And right now we’re kind of figuring and then talking with Pete over at Spenard Builders Supply at the truss plant, you know we’re we’re kind of looking at about 40 pounds right now on some of the heavier snow load areas that are on some of the roofs. So, really most people on most, homes are are pretty good shape. But, there’s a caveat, there’s some of the homes that were built in the 70’s, that didn’t have quite the requirements of what we have now with the tip. With our new codes and so the codes back then you could have some houses that actually have a 40 pound trust system that met the requirements at the time but it’s probably a little bit light on the lighter side for them so if people are concerned were kind of letting them know, hey if you’re concerned please either hire somebody to come in and shovel your roof.”
Chief Prior encourages all to evaluate the snow load on your home’s roof system and the risk of collapse. As we enter into the warming trends of late winter/spring ice dams may begin to create water damage.
FEMA’s offers a publication entitled ‘Snow Load Guidance‘ for home owners.
Overstressed roofs typically display some warning signs. Wood and steel structures may show noticeable signs of excessive ceiling or roof sagging before failure.
The following warning signs are common in wood, metal, and steel constructed buildings:
- Sagging ceiling tiles or boards, ceiling boards falling out of the ceiling grid and/or sagging sprinkler lines and sprinkler heads
- Sprinkler heads deflecting below suspended ceilings
- Popping, cracking, and creaking noises
- Sagging roof members, including metal decking or plywood sheathing
- Bowing truss bottom chords or web members
- Doors and/or windows that can no longer be opened or closed
- Cracked or split wood members
- Cracks in walls or masonry
- Severe roof leaks
- Excessive accumulation of water at nondrainage locations on low slope roofs
If any of these warning signs are observed, the building should be promptly evacuated and a local building authority and/or a qualified design professional should be contacted to perform a detailed structural inspection.
Chief Prior also reminds homeowners to check exhaust vents for boilers to make sure they are clean and clear of snow.