Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 26·5.16
Offset ventilators for level access
When floor levels must be lowered to provide level access, offset (periscope) ventilators can be used to provide subfloor ventilation.
If floor levels need to be nearer to the ground to provide level access, subfloor ventilation can be provided through offset (periscope) ventilators.
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