Reducing Plant Sounds from Modern Buildings

Reducing Plant sounds noise pollution and nuisance

We are Reducing Plant sounds from modern buildings.

Let’s start with what is noise pollution?
Noun
Unwanted or disturbing sound in the environment that affects the health and well-being of humans and other living organisms.
Noise pollution is an invisible danger. It cannot be seen, but it is present, nonetheless. Noise pollution is considered to be any unwanted or disturbing sound that affects the health and well-being of humans and other organisms.

With technological advancements and the increasing demands of modern life comes more impact, both positive and negative. One of those negatives is noise nuisance and sound pollution. Noise is often an inevitable and ubiquitous consequence of human activity, but it can have a significant negative effect on people’s quality of life, affecting wellbeing and health and as well as economic prosperity and the natural environment and wildlife.
A report published by The World Health Organisation (WHO) identified environmental noise as one of the top environmental hazards to health and well-being in Europe. It causes sleep disturbance, annoyance and there is growing evidence that long-term exposure to high levels of environmental noise is associated with illnesses like heart attacks and strokes.
WHO defines noise above 65 decibels (dB) as noise pollution. To be precise, noise becomes harmful when it exceeds 75 decibels (dB) and is painful above 120 dB. Therefore, it is recommended noise levels be kept below 65 dB during the day and indicates that restful sleep is impossible with night-time ambient noise levels in excess of 30 dB.

From 50 to 90 decibels: At this level the human ear can develop discomfort.
From 90 to 130 decibels: At this level there is permanent damage.
More than 130 decibels: At this level the pain will cause immediate hearing loss.

In many cases, where a noise source contains certain characteristics, such as tonality, impulsiveness, intermittency, irregularity or dominant low frequency content, there is evidence to suggest that it can cause greater annoyance than other noises at the same level.

The more compacted we become as a population, the more we will inevitably encounter aspects of contemporary living that will test our patience and capacity to endure our surroundings. Creating an atmosphere where people can live alongside the services, amenities and sources of energy that they require is vital for developing communities. Noise control and the necessity for installing acoustic louvres is becoming a more prominent aspect of modern living and working because of the mix of residential, retail, leisure and industrial expansions in recent decades.

What are acoustic louvres and how do they work?

Acoustic Louvres are external weather louvres featuring acoustically absorbent blade elements. They are specifically designed to reduce the level of noise passing from one side of the acoustic louvre to the other.
Using an aerodynamic structure designed to reduce sound pressure, acoustic louvres provide attenuation (noise reduction) while maintaining the required airflow. Screens are a vital component of any acoustic louvre.

Why are acoustic louvres needed and where are they used?

Typically used in building openings, acoustic louvres can be used as acoustic screens around mechanical plants where airborne noise needs to be reduced, diverting plant and generator sound away from noise sensitive areas, while simultaneously allowing continued airflow for equipment requiring ventilation.

Acoustic louvres can be used in the following locations and situations:

Inside and surrounding boiler and plantrooms in residential areas or on rooftops.
Large-scale industrial applications include power stations, cooling towers and chemical treatment plants
Factories
Areas where control of mechanical fan noise is required
General purpose ventilation
Also worth noting that acoustic louvres are used in areas of high traffic and car parking facilities to mitigate noise pollution

What is a plantroom and what does it house?

A plant room (sometimes referred to as a mechanical room or boiler room) is a room or space inside or outside a building dedicated to the mechanical equipment required to provide or supply building services such as ventilation, electrical distribution, water etc. and its associated electrical equipment, as opposed to rooms intended for human occupancy or storage.

The size of a plant room is normally proportional to the size and type of building. Large buildings may have several plant rooms, or spaces that occupy one or more storeys and some plant rooms may have specific functions, such as battery rooms, transformer rooms boiler rooms etc.

Depending on the size of the building and the nature and complexity of the building services required, plant rooms may contain (amongst other things):

Air handling units
Boilers and thermostats
Chillers/refrigeration HVACR (heating, ventilation, air-conditioning and refrigeration) units.
Heat exchangers
Water heaters and tanks
Water pumps (for domestic, heating/cooling, and firefighting water) and pipework
Main distribution piping and valves
Sprinkler distribution piping and pumps
Electrical equipment and control panels
Back-up electrical generators and compressors
Lift machinery
Gas pipework
Switch gear
Batteries
ITC systems
Humidifiers
Ducts and filters
Specialist equipment for swimming pools, factories etc.
Other HVAC (heating, ventilation and air-conditioning) equipment

HVAC can be used in buildings to:

Maintain internal air quality
Regulate internal temperatures
Regulate internal humidity

What noises do acoustic louvres typically reduce?

As modern buildings contain a variety of amenities for contemporary living and working, acoustic louvres are typically used to reduce noise from sources in building services.
These include but are not limited to:

Fans
High velocity/high pressure terminal units
Grilles and diffusers
Fan coil units
Induction units
Air conditioning units
Fan-assisted terminal units
Rooftop units/air handling units
Chillers and compressors
Pumps
Boilers
Heat rejection and cooling towers
Chilled ceilings
Lifts
Escalators
Electric motors
Noise from water flow systems

What are the other advantages of acoustic louvres?

As well as efficiently mitigating noise, acoustic louvre systems are an ideal solution for offering a level of weather protection for external plantrooms; helping to prevent weather damage such as rain ingress and other debris from entering the area that the louvres are protecting. With external acoustic louvre panels, fully integrated support steelwork systems can also be provided, which are designed to withstand windloads. As our weather becomes more extreme and erratic, louvres are providing robust protection against the elements.
Louvres also offer privacy, preventing see-through to potentially valuable equipment. Additionally, tamper-proof and climb-proof louvres can act as security barriers or enclosures deterring people and animals from entering an area that houses vital machinery therefore safeguarding the equipment against damage and possible interruption to service. It also protects potential visitors/intruders from harm. In an age where safety is of the highest importance and litigation is rife, taking preventative measures to avoid injuries and even possible fatalities is of the utmost importance.

Can acoustic louvres be custom designed?

Regardless of size or shape, Solinear has the capacity to design, manufacture and supply acoustic external louvre panels to suit any size aperture and adjust the louvre construction depending on acoustic attenuation required. Larger scale items normally supplied in modular form for assembling on site. Acoustic louvres can be manufactured and assembled as individual units or alternatively, interlinked to accommodate any size openings and bespoke requirements. If a complete self-contained arrangement is required then standard accessories including corner units, supporting steelwork, doors and blanked sections are used to form the structure.
Height variations of a building can be taken into account to manufacture bespoke acoustic louvre systems of appropriate size. Facade cohesion can also be achieved with acoustic and architectural screening manufactured to the same colours, themes, etc.

Considerations for incorporating plant rooms and acoustic louvres into a modern building

As contemporary living and working places more demands on a building, there are a variety of elements to consider when planning and incorporating plant rooms and acoustic louvres into a building.

These include:

Planning

Site factors
– Ensure ease of access for maintenance and/or replacement of equipment is addressed in locating new plant rooms.
– Consider future expansion possibilities when locating and sizing plant rooms.
Room and Spaces Planning Requirements
– Allow 800mm minimum circulation width through plant room space – 1m preferred.
– Consider equipment and parts replacement when planning circulation zones.
Other
– Allow for a minimum of 20% additional space on boards and in cabinets for equipment expansion.

Roof

General
– Required where plant room is exposed and equipment is not recommended for external placement.
– Light weight roof to designer’s specification.

External Walls

General
– Louvred or naturally ventilated facade preferred.
– Screening devices to be used where plant is externally located and in public view.

Openings

Windows
Window Selection Requirements
– Louvred or ventilated facades are preferred.
Glazing
– Glazing not required.
Visual Privacy
– Equipment to be concealed from public view.

Doors

Door Type
– Louvre doors where external
Door Function
– Lockable – swipe access preferred. Access should be restricted to authorised maintenance personnel
Fire / Acoustic Rated
– Fire rated / acoustic doors as required.
– Fire rated door if required to BCA requirements
Frame Type
– Steel or aluminium frame

Acoustics

Noise level
– Acoustic attenuation required when in proximity to teaching or office spaces.
Noise emittance
– Consider noise emittance when plant room is adjacent or near to a teaching or office spaces.
Room to room
– Minimise sound transmission to adjoining spaces.

Services

Ventilation

Natural ventilation
– Preferred. Plant rooms require constant ventilation.
Air supply
– Natural/passive preferred.
Exhaust
– Required in plant rooms where equipment generates heat.
Controls
– Localised and via the building management system (BMS).

A number of these requirements are factors that will impact on the configuration and quantity of louvre panels required. It’s worth noting that as noise pollution has serious implications for people and the environment resulting in potentially severe consequences, acoustic louvres should never be an afterthought and should always be incorporated into new builds where there will be noise emitting from a plantroom. More detailed guidance can be found in BS8233 (2014) – “Guidance on sound insulation and noise reduction for buildings”.

What Is BS8233 and how can it help?

BS8233 (2014) – “Guidance on sound insulation and noise reduction for buildings” is the British Standard frequently referred to by Local Authority planning departments to ensure that residents of proposed new build or refurbished developments have satisfactory noise insulation and are suitably protected from noise outside of their building with a view to achieving, for example, reasonable sleeping/resting conditions.
The BS8233 guide examines the issue of noise in and around buildings and provides definitions of numerous acoustic terms. Basic information is provided within the standard for non-specialists who have dealings with acoustics, together with more detailed information for acoustic specialists. The standard explores the control of noise from outside the building, noise from plant and services within it and room acoustics – suggesting appropriate criteria and limits for diverse situations.
BS8233 sets out maximum indoor ambient noise level targets for spaces within buildings when unoccupied with the intention of providing a preferred level of acoustic comfort in commercial premises and suitable conditions for resting and sleeping in residential accommodation.
The BS8233 guide sets out minimum ambient noise level targets for spaces within buildings when unoccupied with the aim of providing a preferred level of acoustic privacy in spaces such as restaurants and open plan offices.
This code of practice draws on the findings of research and experience to provide information on the design of buildings that have internal acoustic environments appropriate to their functions. BS8233 is intended for use by non-specialist designers and constructors of buildings and those concerned with building control, planning and environmental health as well as acoustic consultants. The guide also includes useful information on sound insulation within residential properties, Noise Rating (NR) Curves and sound insulation values of basic building materials and construction.
BS8233 also gives guidance on noise levels from industrial noise as well as construction, road, rail and aircraft noise.

Potential hazards of not mitigating plantroom noise

If the noise from a plantroom is considered harmful and is not mitigated with the installation of noise inhibiting methods, then issues could arise ranging from:

Informal complaints by individuals or groups
Formal complaints by individuals or groups,
Vandalism
Injurious publicity
Legal action
Poor reviews
Negative social media exposure
In extreme cases, physical assault of a business owner/building owner/manager
Closure or short-term/long-term interruption of business

The following comments were made by people with complaints and concerns about plant room noise:
“…The worst was yet to come…. we discovered that our room was next to what appeared to be the 2nd floor ventilation room and the noise and vibration coming through the wall was the most horrendous screeching noise which I couldn’t even mask it wearing headphones!… why you would put a bed right next to a plant room with no soundproofing is just beyond belief and I would imagine that the building inspector would have something to say about it.”
This review for a hotel was posted online, possibly resulting in a detrimental effect on business.

“Neighbours planning application includes a ‘plant room’ right up against our boundary wall – noise issues? We are going to get proper advice from an architect, but just wondering if anyone has experienced similar, or if your own ‘plant room’ is noisy? The building is going to be high and overbearing also, but our main concern is a noisy pump or boiler disturbing our peace….”
This concern was raised in an online forum highlighting concerns people have about potential plant room noise.

As noise pollution can be considered highly detrimental to both health and the environment these can be unwelcome but sometimes predictable consequences of not addressing nuisance noise. A nuisance can be difficult to establish but, generally, if something is unreasonable to the average person, a court might decide it is a statutory nuisance.
Depending on location there may not be many standard noise regulations in which case local councils and governments are charged with devising and maintaining their noise ordinances. These may range anywhere from minor regulation to severely strict noise control. Noise nuisance is covered by Part III of the Environmental Protection Act 1990 (EFA). This law requires a local council to investigate complaints of noise coming from fixed premises such as factories, shops, pubs and dwellings.

Governmental policy on noise and sustainable future development

Depending on location, future developments may be subject to stricter guidelines on noise control.
The Government’s policy on noise is set out in the Noise Policy Statement for England. Its vision is to: “Promote good health and a good quality of life through the effective management of noise within the context of Government policy on sustainable development.”
Its objectives are to

avoid significant adverse effects on health and quality of life;
mitigate and minimise adverse impacts on health and quality of life; and
where possible, contribute to the improvement of health and quality of life.

The Noise Policy Statement for England provides the policy framework to assist the implementation of the Environmental Noise Directive and the Regulations. Whilst the Noise Policy Statement for England is not legislation and local authorities are not legally bound by it, Defra has an expectation that local authorities will take it into account in relevant situations and react accordingly.
Identified quiet areas will become a significant consideration in planning decisions with relevant local authorities expected to implement measures to preserve the quietness, or comparative quietness of the spaces. Local authorities in particular should aim to protect them from an increase in noise from transport and industrial sources arising both within and outside the site and which would result in a loss of the perceived sense of quietness.
People in urban areas particularly value the ability to enjoy areas of quiet or relative quiet, away from the sounds of urban life. There is evidence to suggest that quiet (or the absence of unnecessary or inappropriate sounds) has numerous important and often co-related benefits to wellbeing.
Access to quiet areas could also offer other economic and social advantages including influences on property values (people generally prefer to live in quiet neighbourhoods) and benefits to the wider community, including for children and elderly citizens. Consequently, there is a desire to protect areas of quiet and relative quiet to support health, wellbeing and quality of life.
Where possible, the aim is to improve health and quality of life through the pro-active management of noise while also considering the guiding principles of sustainable development, recognising that this will deliver potential benefits to society. The protection of quiet places and quiet times, as well as the enhancement of the acoustic environment, will assist with delivering this aim.
To preserve their quietness, Environmental Noise Directive quiet areas will become a substantial consideration in planning decisions and local authorities will need to implement measures to aim to protect them from an increase in environmental noise arising both inside and outside the space.
Measures to preserve Environmental Noise Directive quiet areas
Once identified, local authorities will be expected to execute measures to preserve their quiet areas and prevent any deterioration of the existing ‘quietness’.
This may include:

Appropriate signage
Installing sound barriers / green barriers
Measures to improve the soundscape or acoustic environment of the space
Restriction of certain noise-creating activities
Consideration of quiet areas within planning / development decisions

Solinear is happy to help

Thanks to our in-house design team and UK manufacturing facility Solinear can offer a wide range of products, many of which combine several functions and includes our dedicated acoustic range – Soundex. Acoustic performance, weathering abilities, fire retardancy and aerodynamic performance are certified to ensure a safe, reliable, quality installation and to guarantee noise reductions. They are tested by independent and industry certified bodies to BS ISO 10140-2:2010 standard.
Solinear works closely with end users, contractors and consultants alike to address acoustic issues across a wide range of sectors, industries and organisations including schools, museums, hospitals and offices. Each of our acoustic louvre products is designed to meet demanding requirements as well as being cost-effective.
Our acoustic louvres, along with acoustic louvre doors, can be manufactured from pre-galvanised steel, stainless steel and marine-grade aluminium alloy, with or without decorative finishes such as polyester powder coating.
A friendly and knowledgeable Solinear representative is happy to discuss louvres and the best solution for any acoustic requirements including design, materials, profiles and effectiveness in noise reduction for a more harmonious environment.