🏊‍♂️ Why Down-Lip Purlins Are a Smart Choice for Aquatic Centers

Aquatic centers are highly specialized buildings with complex mechanical needs and aggressive internal environments. From intense humidity to continuous exposure to chlorine-laden air, every detail in an aquatic center's construction must be engineered for durability, functionality, and ease of maintenance.

One such often-overlooked detail is the orientation of purlins—specifically, the use of Down-Turn Lip Purlins. This seemingly small change in profile direction has major benefits when it comes to long-term performance in aquatic facilities.

🔍 What is a Down-Lip Purlin?

A down-lip purlin is a Z- or C-shaped cold-formed steel member where the short return lip on the flange is turned downward, instead of facing upward or inward as in standard profiles. Though simple, this configuration change significantly impacts airflow, drainage, maintenance access, and corrosion resistance—especially in harsh environments like swimming pools.

✅ Why Down-Lip Purlins Matter in Aquatic Centers

1. Reduced Condensation & Better Airflow

Aquatic centers produce large amounts of warm, humid air. Poor ventilation between purlins and roof sheeting can lead to condensation buildup—dripping into the pool or mechanical systems below. Down-lip purlins:

• Improve airflow channels along the underside of the roof

• Reduce stagnant air pockets that trap moisture

• Help maintain drier, more stable roof cavities

2. Enhanced Corrosion Resistance

The high-humidity, chlorine-rich environment accelerates corrosion. Standard upward lips can trap condensation or chlorinated moisture, leading to premature degradation. Down-lip purlins help by:

• Eliminating upward-facing moisture traps

• Supporting quicker runoff and drying

• Extending the life of protective coatings and structural elements

🛠️ The Importance of Proper Detailing

In steel detailing, the lip orientation must be modeled and documented correctly. If the down-lip is missed during modeling, it won’t be fabricated as intended, and site installation will suffer. Key issues include:

• Incompatibility with roof sheet systems

• Incorrect bracing connections

• Reduced service clearance

• Corrosion traps not visible in GA drawings

  
  

Every aquatic center project should treat down-lip orientation as a critical detail—not a cosmetic variation. Detailers must ensure the model reflects the specified purlin direction and coordinate this with the design engineer and fabricator.

Looking for reliable and accurate steel detailing support? Please feel free to reach out to Sharcon for professional steel detailing services tailored to Australian standards and site-ready fabrication.

📞 Call us: +61 478 727 338

📧 Email us: shyam@sharcon.com.au

🌐 Visit our website: www.sharcon.com.au