Commercial Roofing Systems
Different roofing systems offer varying benefits and lifespans.
- TPO Roofing Energy-efficient and durable.
- EPDM Roofing Long-lasting rubber membrane.
- PVC Roofing Chemical resistant and strong.
- Modified Bitumen Traditional and reliable.
Understanding Commercial Roofing
Proper commercial roofing calculations ensure durability and weather protection.
- System Types TPO: 45-80 mil thickness. EPDM: 45-90 mil. PVC: 50-80 mil. Modified Bitumen: 2-4 plies. Built-up (BUR): 4-6 plies. Metal: 24-22 gauge.
- Load Requirements Dead load: 6-12 psf. Live load: 20-40 psf. Snow load: zone specific. Wind uplift: FM 1-90 minimum. Drainage: 1/4" per foot slope.
- Insulation Values R-30 minimum code. Polyiso: R-5.7/inch. EPS: R-4/inch. XPS: R-5/inch. Cover board: R-2.5. Tapered: 1/8-1/2" per foot slope.
- Warranty Requirements 20-30 year standard. NDL coverage. 55-90 mph wind. Puncture resistance. Hail rating. Regular inspections required.
Installation Guide
Membrane Installation
Seam overlap: 3-6". Fastener spacing: 12" O.C. Perimeter enhancement: 50%. Corner enhancement: 100%. Adhesive coverage: 1-2 gal/100ft².
Drainage Design
Drains: 1 per 10,000ft². Scuppers: 6"×4" minimum. Overflow: 2" above drain. Cricket size: 1:1 ratio. Internal drains preferred.
Cost Analysis
TPO: $7-10/ft². EPDM: $6-9/ft². PVC: $8-12/ft². Modified: $9-13/ft². BUR: $10-15/ft². Metal: $12-18/ft². Labor: 40-60% of cost.
Maintenance Schedule
Inspect bi-annually. Clean drains quarterly. Repair punctures immediately. Recoat: 10-15 years. Full replacement: 20-30 years.
Installation Factors
Building Height
Affects equipment and safety needs.
Accessibility
Impacts material delivery and setup.
Weather
Influences installation timeline.
Regulations
Local codes and requirements.
Energy Efficiency
- Insulation Types Different R-values and costs.
- Cool Roofing Reflective properties save energy.
- Ventilation Proper airflow requirements.
- Energy Codes Meeting local standards.
Maintenance Tips
- Regular Inspections Preventive maintenance schedule.
- Drainage Keep drains and gutters clear.
- Repairs Address issues promptly.
- Documentation Maintain service records.