A Guide to Semi Downdraft Spray Booths

Welcome to our dedicated guide on semi downdraft spray booths. Whether you’re a seasoned industrial expert or just getting started, we’ll provide you with all the valuable insights to help you decide whether this type of spray booth is suitable for your needs.


What is a Semi Downdraft Spray Booth?

A semi downdraft spray booth is a specialised enclosure designed for the application of paints, coatings, and finishes. It’s a hybrid solution that combines distinctive attributes from both crossdraft and full downdraft booths. A ventilation system draws air from the upper portion of the booth and exhausts it through filters located at the rear. This configuration creates a controlled airflow pattern that directs overspray away from the operator and the object being painted.

How Does a Semi Downdraft Spray Booth Operate?

In a semi downdraft spray booth, air is introduced into the booth through a filtered intake plenum positioned at the upper section. This air is then guided diagonally across the work area, carrying overspray particles away from the operator. The air is finally exhausted through filters situated at the rear of the booth, ensuring clean air circulation.

Downdraught Booths

Benefits of Using a Semi Downdraft Spray Booth

Semi downdraft spray booths offer several advantages for industrial painting processes:

  • Effective Overspray Control – The airflow pattern in semi downdraft booths effectively captures and contains overspray particles, reducing the risk of contamination and improving paint transfer efficiency.
  • Improved Air Quality and Worker Safety – By directing the airflow away from the operator, semi downdraft spray booths help maintain a clean and safe working environment, minimising exposure to harmful fumes and particulates.
  • Energy and Cost Savings – The airflow design of semi downdraft booths reduces the volume of air that needs to be heated or cooled, resulting in energy savings and lower operational costs. Furthermore, these booths eliminate the need for costly concrete installation and as such, are an excellent choice for those on a budget.
  • Improved Productivity – The efficient overspray control and improved airflow pattern contribute to faster drying times and shorter paint curing cycles, increasing overall productivity.

What Industries are they used in?

Semi downdraft spray booths are used in various industries, including:

  • Automotive Refinishing – These booths are ideal for automotive body shops and collision repair centres, providing a controlled environment for painting cars, trucks, and other vehicles.
  • Aerospace Manufacturing – Semi downdraft booths excel in achieving high quality finishes for aircraft components, including fuselages and wings, while adhering to rigorous industry standards.
  • Woodworking and Furniture Production – The controlled airflow in these booths enables precise application of finishes on wooden furniture, cabinets and other woodworking projects.
  • Industrial Coatings and Painting Processes – Semi downdraft spray booths are suitable for a wide range of industrial applications, such as metal fabrication, machinery painting, and equipment coating.

What’s the difference between Downdraft and Semi Downdraft Spray Booths?

Full downdraft spray booths draw air vertically from the ceiling to the floor, whereas semi downdraft spray booths draw air diagonally from the upper portion of the booth towards the exhaust filters. The main difference lies in the position of the air intake and exhaust systems, affecting the airflow pattern and the level of overspray control achieved.


How Can Unitech Machinery Help?

At Unitech Machinery, we specialise in the design and manufacture of high-quality industrial spray booths, including semi downdraft spray booths. Our team of experts can assist you in selecting and customising the right booth for your specific needs. We provide comprehensive support, from installation to maintenance, ensuring optimal performance and customer satisfaction. Contact us today on 01543 685565.