# Excessive use of Flexible Ducitng leads to Poor Exhaust Systems ### Issue Image: ![[Pasted image 20250203154602.png]] ## Issue Description: 1. Excessive use of flexible exhaust ducting produces high static pressure and potential for crushes and tears to the flexible ducting from sheeting the ceiling 2. This will substantially reduce the performance of exhaust and Air Conditioning Systems. 3. Where possible, use rigid ducting. 4. NOTE, rigid ducting must comply with Specification C1.10 of the BCA, 5. PVC plumbing pipes Does not comply. 6. Joints between rigid ducting pieces should all be sealed with either Tape or Sealant. ## Actions to Prevent this Issue: - [ ] Mechanical Engineer design and exhaust and AC systems so at most 1.5m lengths of flexible ducting are used. ## Source