Truss Blocking is blocking soffitt ventaliation to attic

[smitty9898]

I've been asked to develop a repair procedue for 10 4-story residential apartment buildings. Standard brick buildings with wood trusses that are approximately 40' long.

The buildings are currently having ventilation problems.

During my investigation, I found that there is no opening at the blocking between the joists at the their bearing points. The joists are spaced at 2' o.c. and the blocking is a 2x6. No airflow is occurring between the joists. There are soffit vents on the outside, but they are basically useless. I need to get about 20 square inches of ventilation between each truss. Any ideas? I would imagine this is a common problem.

Thanks, Ryan

 

[lilliput1]

There must be a minimum 1" high space between the bottom of the roof and the top of the insulation on the attic floor to let ventilation air from the soffit vents through. Also it is recommended to have high ridge vents to vent the air out coming in from the low soffit vents. See the building code.

 

[RossABQ]

Drill holes in the blocking? You don't need a solid piece of wood for blocking, it's just to keep the trusses from tipping over. If you can replace them without doing major damage, replace them with crossed metal braces (an "X").