A Tall Order: HVAC Riser Cleaning and Coating

Common Challenges with Risers

Accessing and maintaining HVAC Risers can be challenging due to their central placement within a building or attachment to an outer wall. Typically spanning multiple stories, HVAC risers are crucial for multi-story buildings and high-rise structures, enabling centralised control of climate systems and ensuring consistent indoor air quality and temperature.

Types of HVAC Risers:

• Ventilation Risers: Carry air to different floors for ventilation and temperature control.
• Exhaust Risers: Distribute exhaust air from bathrooms, kitchens, or industrial spaces to the building's exterior.
• Riser Pipes: Used to transport water to and from cooling equipment.

Riser cleaning refers to the maintenance and cleaning of a building's vertical utility shafts or risers. Extract Risers, in particular, are notoriously difficult to access, inspect, and maintain due to their positioning—either running through the centre of a building or bolted onto an exterior wall. Their height and required roof access further complicate maintenance.

Neglecting riser cleaning can lead to severe consequences, including:

• Blockages due to accumulated debris such as dust, dirt, and building materials. (See image below: Clogged riser with debris)
• Hygiene issues, as damp or dirty conditions can promote microbial growth.
• Fire hazards resulting from combustible buildup.
• Potential non-compliance with building regulations or insurance policies, leading to fines or required remedial work. 

Solutions to Cleaning and Maintaining Risers

Proper maintenance and cleaning of risers require specialised techniques and equipment:

✅ Robotic Equipment – Advanced robotic inspection and cleaning devices allow for thorough assessments and maintenance in hard-to-reach areas. 

✅ Far-Reaching Equipment – Telescopic and extendable tools help technicians clean risers efficiently without full physical entry.

✅ Rope Access Technicians – IRATA-certified professionals use climbing equipment to access and maintain risers safely.

✅ Debris Removal and Cleaning – Specialised suction and filtration systems remove blockages and improve airflow efficiency.

✅ Insulation Encapsulation or Replacement – Protects risers from external damage and ensures insulation remains effective.

✅ Antimicrobial Coatings – Application of antimicrobial treatments prevents bacterial growth and improves air quality. 

By implementing these solutions, property managers and building owners can ensure that HVAC risers remain clear, compliant, and efficient, contributing to a healthier indoor environment.

VIDEO The antimicrobial coating of a vertical duct riser using an airless sprayer with a rotary attachment and inspection camera. The setup is lowered into the riser via a pulley system, allowing for full 360-degree coverage of hard-to-access ductwork.