- BuildingDesign Construction Portal
  • Request Product Information
  • Connect With Us
  • Follow BuildingDesign on Twitter Connect with BuildingDesign on LinkedIn Become a fan on Facebook Follow BuildingDesign on Pinterest instagram

Systemair - Swimming Pool Ventilation Guidelines - Menerga

Pool Hall Humidity - Energy Consumption - Heat Recovery - Air Distribution - CIBSE Guidance

Typical Conditions

The pool hall temperature in most public pools is maintained around 30°C. To limit the evaporation of water from the water surface, it is common to have the pool water temperature 1-2°C lower than the pool hall temperature. With respect to the comfort conditions for the bathers, it is acceptable for the humidity to remain within a range of 50% to 60%.

Pool halls require more energy than any other public building (by an order of magnitude) with virtually year-round heating (in the UK). Fan motor power consumption is high because the ventilation system runs continuously. Ensuring minimum energy for the air supply has a much bigger impact than focusing on the water (which can only be heated at a rate of 0.5°C per day and once at temperature requires minimal input).

When calculating the amount of fresh air required for dehumidification, please consider the following:

  • The surface area of the pool & characteristics of the pool usage
  • The difference between the vapour pressure of the pool water & the vapour pressure of the saturated air in the pool hall
  • The air changing rate should be between 4-6 per hour according to the air distribution principle
  • CIBSE guidance currently states 10 l/s per m² total floor area (based on a public pool 25 x 13m)

To calculate the heating demands of the pool hall, the following calculations are required:

  • Transmission loss
  • Energy lost due to the heat required for water evaporation
  • Heat energy required to cover the water evaporation

Temperature, Humidity Control & Energy Consumption

Most pool units are designed to ventilate, heat and dehumidify a space.

To ensure the best performance at the lowest lifecycle cost, several key factors should be noted:

  • Fully controllable eC direct drive fans – no one should be using belts in this day & age
  • The ability to maintain a small negative pressure at all times – through varying usage & volume requirement, with as close to balanced air flows to maximise heat recovery
  • High passive heat recovery efficiency – so there is no penalty for introducing outside air >95%
  • Minimal (ideally no) metallic parts in the air paths to avoid corrosion or acid attack
  • Polypropylene based recuperators, ABS grade fixtures & fittings, flexible duct connections, plastic damper cogs
  • Accurate, self-contained, real time control systems – the unit must be able to calculate the most efficient mode of operation from real time measurements of outside & return air conditions at all times

Pool Hall Air Distribution

The best unit in the world cannot compensate for poor air distribution. The air distribution should be able to bring the evaporated moisture direct to the return air inlet. There are two reasons that make this function significant.

One is to get the moisture out, the other is to get rid of the disinfection by products coming in to the pool hall with the evaporation of the water. The best method for this is a floor level induction diffuser and a return air system which takes the air out with several inlets.

Outside Air Requirement

Under UK CIBSE guidance, a minimum of 30% outside air is required at all occupied times to supply a public swimming pool. For much of the year, this proportion of outside air is sufficient to dehumidify the pool hall.

By maximising heat recovery efficiency there is no penalty to introducing more outside air when required, ensuring running costs are simply for top up heating to overcome fabric transmission losses within the space, and power for the constantly running fans. The ability to have full outside air bypass is critical to ensuring good conditions year-round in the UK.

By eliminating the need for a heat pump, you can reduce electricity costs, maintenance costs and minimise the number of components that can fail.

Why pay for a heat pump and additional circulation electricity when the outside air required by law can dehumidify for you for the cost of running the fans?

Systemair Menerga Logo

Click the PDF image to view the technical information in full


Request Systemair Info

Systemair Ltd
Unit 28
Gravelly Industrial Park
B24 8HZ

Email Systemair

Tel: 0121 322 0200
Fax: 0121 322 0201

View / Print Content (PDF)

Click to enlarge

Request Information From Systemair - for UK and Europe only

  • *Full Name
  • *Company Name
  • *Telephone
  • *Email
  • *Enter Short Description of Your Requirements
Please tick below to indicate how Systemair may contact you. You may leave any box blank.
  • By Email
  • By Post
  • By Phone
  • By SMS

To Subscribe to our twice-weekly BuildingDesign e-Newsletter tick here:

  • * Please enter numbers shown for validation purposes
We will not share any of your details with any third parties or subsidiaries. You have the right to withdraw or change your consent at any time by contacting Systemair. Company details can be found here »

Click here to read our Privacy Notice »