Repairs To Field Modified Damaged Trusses
Question:
As a home inspector, I have recently inspected an existing home with an attic truss system installed. Several of the truss web members have been cut away to allow access to an attic-mounted heating system. Can you recommend repairs to a truss with cut web members?
Answer:
Unfortunately there is no standard repair detail available for field modified or damaged trusses, as design conditions and the extent of the damage vary considerably from job to job. It is very possible that the damaged trusses you have described can be repaired. The repair will most likely require reinforcement of the bottom and/or top chords with additional lumber as well as reinforcement of the remaining web joints with a field-applied steel plate or structural sheathing.
The repair should be designed by a qualified individual. Your first choice should be the original truss manufacturer, as they are most familiar with the product. The truss manufacturer will be able to compare the current in-use conditions with those of the original design and, for a fee, develop an acceptable repair. In the event you are unable to determine or contact the original truss manufacturer, a registered design professional experienced with wood truss design can be hired to design a repair.