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Acoustic Planning Aid for Indoor Swimming Pools and Spa Areas


Tips for better acoustics in indoor swimming pools and spas

„Noisy sport in quiet halls“ - under this title, the Fraunhofer Institute for Building Physics (IBP, Stuttgart) published a study on acoustic conditions in swimming pools in 2015.

The key message: Those asked stated acoustics as the biggest area of dissatisfaction. Noise not only complicates communication, but can also lead to concentration problems and in the worst case to health impairments. So how can the acoustics in indoor swimming pools and spas be improved and what should be considered during the planning phase?

Together with 4a Architects GmbH in Stuttgart, we have put together some important tips for positively influencing the volume, speech intelligibility and audibility in indoor swimming pools and spas.

Include acoustics as early as possible in your design.

In contrast to earlier times, structural measures for sound insulation and room acoustics are often already required in the tender phase.

And rightly so: from the beginning, acoustics can be ideally integrated both functionally and economically into the design. This is also the findings of the IBP, who suggest interaction with structural engineering, building physics, architectural and organisational requirements.

DIN 18041 is a good orientation guide

The relevant standard for acoustics in swimming pools and the basis for all designs is DIN 18041 „Audibility in rooms - Requirements, recommendations and guidance for design (March 2016 edition). It also applies to sports halls and swimming pools up to 30,000 m³ in volume.

The standard distinguishes between the requirements in room group A, audibility over medium and long distances - including indoor swimming pools - and room group B , audibility over short distances (e.g. workplaces and restaurants).

The type and intended use of the pool influence the acoustic measures

Every construction project is different. Is it a leisure facility, sports facility or spa? Is there a private or public operator? Depending on the type of indoor swimming pool, different requirements apply to the acoustics.

Another important criterion is whether the swimming pool is also designated as a meeting place. If so, higher technical requirements apply, for example, in terms of fire protection.

When doing renovation work, take into account the structure of the indoor swimming pool

In the 70’s, acoustic measures in swimming pools were hardly an issue. The challenge: Many of these pools are dome structures, which are the hardest to renovate in terms of acoustic criteria compared to other building forms.

Even with modern acoustic solutions, the acoustics in domed pools remain unsatisfactory. In all other construction forms, the acoustics can be readily improved.

Plan effective acoustic separation of the different areas of use

The slides next to the relaxation area? That could become a problem. Water attractions are considered one of the largest noise sources in the building and should be positioned intelligently. Not only the location of the area plays a role. Most pool operators demand a consistent separation of different areas in the building such as sports pools, leisure and play areas, water attractions, changing and gastronomy zones.

However, it is not possible to avoid unwanted noise with boundary surfaces alone. In some cases, structural measures such as dividers or zoning must be used in order to achieve the appropriate conditions.

In our best practice example of the Water World in Langenhagen , floor-to-ceiling glass partition walls between the sports and diving area as well as between the diving and adventure areas, ensure acoustic separation. At the same time, transparency and visual relationships in the swimming area are maintained throughout.

Coordinate the substructure together with all fixings with the requirements of the pool

In addition to physical demands, the chemical influence of chlorine fumes or salt in saline pools, places a huge demand on the substructure. These are significantly more corrosive than high humidity or water. Ensure a substructure with a suitable material is selected.

It is recommended for example to use wooden sections, which depending on the type of wood used require no chemical wood preservation (use classes according to DIN 68800-1). However, classic drywall profiles and accessories with corresponding corrosion protection class C5 according to ISO 12944-2 are also an option.

Create pragmatic solutions in the design of form and space

On the one hand, swimming pools and spas, in their partly natural surroundings, allow scope for the design of form and space. On the other hand, pragmatic solutions are often needed. Sloping fronts and roof structures, for example, not only allow better room acoustics. The large room heights can also be used for diving towers or slides.

Find a compromise between design and acoustics in the ceiling design

Ceilings are often the only surfaces on which acoustic measures can be carried out at all. At the same time, they are also important design elements in a swimming pool. For example, colour-coordinated ceilings made of wood wool acoustic panels (for example HERADESIGN® superfine 25mm by Knauf AMF) set special accents in a spacious swimming pool.

With different colours - E.g. blue tones for the sports area and warm yellow and orange tones for the leisure area - you can give the individual areas their own atmosphere and visually separate them.

Identify the necessary absorbent surfaces with a simple table

Depending on the room group and the volume of the room, the required absorption area can be approximately determined. A simple table makes the calculation easier and supports you in choosing the right material and system. We will demonstrate how this is done in our planning aid .

Avoid flutter echoes by considering room acoustics as a whole

Flutter echoes are an underrated side effect of one-sided distribution of absorption surfaces. To avoid this, it is important to consider the room acoustics as a whole. This means not only an absorbing ceiling, but also measures on walls should be used. Large tiled areas on walls often cause acoustics problems (see also planning aid page 11).

If, as in “Wasserwelt Langenhagen“, special acoustic wood wool tiles are used, an acoustically effective design element can be created by continuing the ceiling on up to one third of the walls.

As a result, the proportion of sound-absorbing surfaces increases across the entire facility, without any loss of transparency or incidence of light. Speech intelligibility must be considered in all areas, in order for visitors to easily understand organisational and safety announcements.

Download planning aid with planning table and practical test now!