If Your Bowstring Trusses Could Talk, What Would They Say?

January 20, 2025

Probably ‘Please, please pretty please, keep the roof drains clean.’

One of the most common repairs we complete is a rotted end, often caused by clogged roof drains. What happens? Your roof drains fills with leaves, twigs, whatever, during a rain the water backs up to the point where you have a puddle on your roof. Your roof is not designed for standing water, so the water leaks inside your building.  Often there are roof drains located near the end of bowstring truss. The water runs down to the end of the truss, soaking the end of the truss (the truss ends carry the weight of the truss and roof). Overtime this causes the truss end to rot and then fail. If you're lucky the rotted end is identified and repaired before the truss completely fails only costing you several thousand dollars, if you're not…….


Picture of a classic rotted end.

A picture of a roof with the words deflected deformed top chord cracked bottom chord and sagging bottom chord
A picture of wood at truss end rotted due to roof leak.
A large building under construction is covered in snow
January 15, 2025
The most likely time for your trusses to fail is during a major snowstorm. The snow can add significant weight to your roof. Snow and then rain are the worst combination possible. A foot of snow can weigh 10-20 lbs per square foot of roof area. One inch of rain absorbed by the snow can add an additional 5 lbs per square foot. (current design snow load is 25 lbs per square foot, your 100-year-old building was very likely designed for less). So, you can see this could be a problem. But you say, ‘My building is 100 yrs old and has seen everything, I’m not worried. If it hasn’t failed in the last 100 years, why would it fail now?’ It has been a couple of years since we have had a major snowstorm in the Chicago area and things could have changed with your trusses since the last big snow. What could have changed: A roof leak could have rotted portions of your trusses. Termites could have eaten portions of your trusses. A truss could have been damaged by impact by something…a forklift a truck. Maybe someone decided to attach a chain fall to your truss to do some heavy lifting. A small crack or imperfection in the wood could have worsened or could worsen with additional weight. Any number of things could have happened to place your roof at risk. So what do you do? Call Wooden Roof Solutions for a free visual inspection of your bow string trusses and give yourself some peace of mind when the snow finally flies.
The ceiling of a building under construction is made of wood and metal.
April 8, 2024
An architect's dream that presents special challenges
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