WITH MANY HOTELS OFFERING GUARANTEES of a good night’s sleep, the control of sound is of paramount importance even in budget hotels. However, each of the major hotel chains takes a different approach to how they specify acoustic performance, so there are real dangers for the design team. For example, one hotel chain may require airborne sound insulation to be assessed against STCs, while another may assess against DnT,w +Ctr.
As well as a variety of on-site performance parameters, each hotel chain sets differing performance criteria and it is not sufficient to assume that a higher-rated hotel will automatically require higher levels of sound insulation between rooms. The good night guarantee for budget hotels can mean that they set higher standards than more prestigious hotel chains.
This chapter provides examples of good practice across the hotel industry. The performance standards that are included have been gleaned from a variety of hotel design projects, taking the most onerous standards to define best practices and outline key areas to watch out for when involved in the design of any hotel.
14.2.1 Performance specifications
Acoustic performance levels in hotels are dictated by a number of key factors. With regards to sound insulation between rooms, the most strict criteria would be required:
if a hotel is likely to be used regularly by guests who need to sleep during the day, e.g., hotels near an airport which are to be used by flight crews
if the hotel chain wishes to offer a money-back guarantee for guests who do not get an uninterrupted night’s sleep.
The most strict controls on ambient noise levels are more likely to be required:
if a hotel is to be located within a noisy city center location close to high transportation noise
if a hotel is to include large function suites or hopes to gain a significant portion of its income from bars and restaurants open to non-residential guests.
Specific guidance levels for ambient noise control, acceptable mechanical noise levels, maximum permissible reverberation times, and airborne and impact insulation requirements are detailed in Appendix B.
14.2.2 Maximum permissible noise levels from external sources
It is often expected that maximum permissible noise levels are applied in hotel design to avoid disturbance from infrequent high-noise events such as may be common in an urban location (delivery noise, people shouting in the street). Suitable levels are detailed in Table 14.1. Particular care should be taken when applying a maximum noise criterion and discussions with the client should be sought at the design stage. This is because it can often be impractical or extremely costly to achieve the control of sudden or very loud noise events.
The following guidance should be applied when considering the use of control standards on maximum noise levels or LAmax:
Function rooms – LAmax for function rooms are generally only applicable if there is an expectation that the function room is to be used for lectures, conferences, or other events where public speaking is anticipated.
Guest bedrooms – The LAmax criteria for guest bedrooms is commonly only applied during the nighttime period.
Frequency of high-noise events – when assessing LAmax it is anticipated that it should apply to regular occurrences (e.g., events that would occur more than 10 times during the night (11:00PM–7:00AM). Therefore unless the hotel is next to a fire or police station, then sirens from emergency service vehicles should be discounted.
Naturally ventilated buildings – The use of naturally ventilated designs is popular due to their eco-friendly benefits; however, the use of natural ventilation is at odds with the control of noise break-in to a hotel. If existing noise levels on a hotel development site exceed an LAeq (nighttime) of 62 dB and/or an LAmax of 72 dB, then it can be assumed that mechanical ventilation will be required.
14.2.3 Noise limits for heavy rain
Noise from heavy rainfall can also be a cause of disturbance within hotel developments. It is likely that such an issue would only be of concern for rooms on the top floor of a hotel or where the hotel is only a single story in height. Here the application of the NR or NC parameter is suitable, and the required performance levels are detailed in Table 14.1.
Table 14.1 Control levels for various noise sources – hotel
Room | External sources (Section 14.2.2) | Rain noise (Section 14.2.3) | Lift/elevator noise (Section 14.2.4) |
LAmax(f) dB | NR/NC | LAmax(f) dB | |
Guest bedroom | 40 | 40 | 25 |
Meeting room | 45 | 45 | 30 |
Function room | 50 | 45 | 30 |
Lounge | 50 | 45 | 30 |
Bar | 50 | 50 | n/a |
Restaurant | 50 | 50 | n/a |
Lobby/foyer | 55 | 50 | 50 |
Reception | 55 | 50 | 50 |
Office | 50 | 45 | 40 |
Table 14.2 Sound insulation performance requirements, hotel guest bedroom to hotel guest bedroom, depending on separating construction type
Construction type | Minimum Rw/STC (dB) |
Reasonable performance levels | 58 |
Good performance levels | 63 |
14.2.4 Control of noise from lifts/elevators
Lift/elevator noise can be of concern particularly where there are limited opportunities to separate lifts/elevator and lifts/elevator lobbies from guest bedrooms. Suitable performance levels for hotels are detailed in Table 14.1.
14.2.5 Sound insulation between guest bedrooms within a hotel
The primary area of concern in any hotel is the partitions that separate one guest bedroom from another. Performance standards for airborne sound control, given in Table 14.2, depend on performance.
Performance levels for impact sound are detailed in Table B.1.
Note: Achieving “good” insulation levels is not in itself an absolute guarantee that guests will not be disturbed by noise. It is a performance level that ensures that most people would not be disturbed by noise from a neighboring room and reduces the risk to the hotel operator.
14.3.1 Controlling external noise
The following guidance should be considered when appraising the orientation and layout of a hotel to control external noise break-in:
Orient guest bedrooms away from a direct line of sight to a significant noise source, e.g., road, industrial site.
Consider the use of fixed glazing and mechanical ventilation where external noise levels exceed LAeq 62 dB and/or LAmax(f) 72 dB at 3 ft (1 m) from the hotel façade.
Consider the use of primary and secondary glazing along with mechanical ventilation where external noise levels exceed LAeq 75 and/or LAmax(f) 82 dB at 3 ft (1 m) from the hotel façade, e.g., for hotels located next to nightclubs, airports, or very busy roads.
Do not locate guest bedrooms with a clear line of sight to a mechanical room or an area of rooftop units associated with the hotel itself.
Do not place external smoking areas or external drinking and dining areas within 65 ft (20 m) of a guest bedroom window unless their use is restricted to between 10:00AM and 8:00pPM.
Where hotels physically adjoin a residential dwelling, then minimum insulation levels in line with local building codes or standards should be applied.
Where hotels physically adjoin a cinema, the minimum performance criterion should be an STC or Rw of 80 dB. Bedroom to cinema auditoria should always be avoided.
Where hotels physically adjoin a retail space or bar, the minimum performance criterion should be an STC or Rw 70 dB. Locating guest bedrooms directly next to a bar or nightclub with bass-intensive music should always be avoided.
14.3.2 Control of internal noise
Guest bedrooms above hotel bars should be avoided where the hotel bar is open to the general public or is regularly used as a function bar. The location of guest bedrooms above restaurants, kitchens, mechanical rooms, and laundries may be permissible if insulation levels above STC/Rw 75 dB can be achieved.
Locating any of the following rooms above a guest bedroom should be avoided:
bar
restaurant
lounge
function hall
fitness center
public toilet/restroom
spa
kitchen
stair
laundry
shop.
Note: If such adjacencies cannot be avoided, then a minimum requirement of FIIC 75 or L’nT,w 35 dB should be set. Achieving such levels of insulation is only likely to be possible with heavy concrete floor constructions which incorporate an acoustically isolated deep screed (196–328 ft or 60–100 m) finished with an impact reduction layer (matt and/or carpet) and an acoustically isolated ceiling. A typical minimum construction depth of 27 in (700 mm) would not be unusual.
Locating any of the following rooms next to (commonly separating wall) each other should be avoided:
guest bedroom to function room
guest bedroom to bar
guest bedroom to kitchen
guest bedroom to laundry
guest bedroom to mechanical room
guest bedroom to restaurant
meeting room to kitchen
meeting room to laundry
meeting room to mechanical room.
The location of any of the following rooms next to a hotel meeting room will require appropriate room management by the hotel so that activities do not clash:
bar
function room
spa
fitness room
guest bedroom
restaurant.
Do not place function rooms, bars, restaurants, kitchens, mechanical rooms, and laundries along the same common corridor with guest bedrooms.
Do not place rooms with high-activity usage at the far end of a corridor which also has guest bedrooms along it, e.g., meeting rooms, spas, fitness rooms, laundries, etc.
Place doors within corridors to screen off guest bedrooms from foyers or lift lobbies.
Do not place fire doors along corridors within close proximity to the door of a guest bedroom. See Figure 14.1. If this cannot be avoided, then doors should be held open with magnetic doorstops, which can be deactivated in the event of a fire alarm.
Fit corridor fire doors with soft-closing devices and fit brush seals to the doorframe.
Do not provide areas in corridors outside guest bedrooms which entice guests to loiter or gather in groups, e.g., shoe shine, ice machines, seating. Such areas should always be separated from guest-room corridor runs by closed fire doors or located in lift/elevator lobbies.
Laying out bedrooms so that beds back onto beds and desk or wardrobe space backs onto desk/wardrobe space in the adjacent room can help reduce noise disturbance. Place air conditioning outlets as far from the bed head as possible.
Figure 14.2 details an optimum bedroom layout to reduce noise disturbance within a guest bedroom.
14.1 Place doors in corridors away from entrance to guest bedrooms
14.2 Optimum hotel bedroom layout
1) Locate bedheads as far from entrance as possible.
2) Door between bedroom area and en suite helps to reduce noise disturbance from corridor.
3) Position access doors between rooms away from bedhead, creating an area that can be closed off, will help to reduce disturbance when adjoining rooms are not hired out under the same occupancy.
Interconnecting doors between bedrooms will always reduce the overall acoustic performance of the partition. Avoiding noise disturbance therefore becomes a key function of the management of adjoining rooms. For best results when the adjoining doors are not in use, the following is suggested:
A set of twin doors either side of the partition is always preferable.
The doors should be a solid core construction and be capable of achieving a minimum Rw/STC of 35 dB.
Full perimeter seals, including drop seals at the bottom of each door, should be considered.
Locate the adjoining doors as far as possible from the bedhead.
If the hotel function room is likely to be located close to existing dwellings (i.e., within 130 ft/40 m), then it is likely that primary and secondary glazing will be required in function rooms expected to be used for live or amplified music. A standard double-glazed unit with a 4 in (100 mm) cavity and a secondary unit with a laminate glass (e.g., 1/3 in/8.8 mm) is common.
Any bar associated with a function room should be located away from the intended location of any live or amplified music, to reduce risk to staff hearing.
Where movable walls are used between function and meeting rooms, performance standards of above STC/Rw 55 dB should be sought from the manufacturer. Hotel operators should be made aware of the expected reduction in acoustic performance between fixed walls and movable walls. The need for flexibility of space should be weighed against the need for acoustic performance.
14.3.3 Avoiding risk – partition details
Boxing around the rear of electrical sockets within separating walls with plasterboard or fitting putty pads to the rear of a socket box can reduce impact noise transmission through guest bedroom walls.
Installing timber or plywood panels between metal or timber stud to offer additional structural support for headboards can reduce overall cavity depths of a guest-room wall. Allowances should be made for any reduction in cavity depth.
Where timber or plywood panels are placed as an alternative to an inner layer of plasterboard, it is important that the board selected has the same surface density as the plasterboard being replaced.
Electrical and mechanical services should be run along main corridors and fed into rooms via the corridor wall. Penetrations through partitions separating any noise-sensitive rooms should be avoided.
Table 14.3 outlines some suitable specifications for ceiling, floor, and wall finishes within a hotel development with reasonable to good levels of control for reverberation.
Table 14.3 Recommended floor, wall, and ceiling finishes by material or absorption coefficient άw (hotels)
Room | Floor άw | Ceiling finish άw | Wall άw |
Corridors | 0.3 carpet (avoid laminate or tile finishes) | 0.8 ceiling if floor is carpeted | Plaster or gypsum board |
0.9 if floor is vinyl finish | |||
Bars | 0.3 carpet preferred, can vary | 0.8 ceiling if floor is carpeted | Plaster or gypsum board |
0.9 if floor is vinyl, timber, or tile | |||
Restaurants | 0.3 carpet preferred, can vary | 0.8 ceiling if floor is carpeted | Plaster or gypsum board |
0.9 if floor is vinyl, timber, or tile | |||
Reception areas | 0.3 carpet preferred, can vary | 0.8 ceiling if floor is carpeted | Plaster or gypsum board |
0.9 if floor is vinyl, timber, or tile | |||
Meeting rooms (small) <5 | 0.3 carpet | 0.8 over 50 percent of ceiling | 0.8 over 25 percent of wall area |
Meeting room (large) >5–20 | 0.3 carpet | 0.8 over 50 percent of ceiling | 0.8 over 25 percent of wall area |
Fitness room | 0.3 non-slip carpet or carpet tile | 0.8 absorptive ceiling below plasterboard or structural ceiling | Plaster or gypsum board |
Swimming pool | Unrated, tile | 0.6 spray finish | 0.4 slotted block or unpainted block |
Steel, C. (2010) Acoustic design assessment. Hotel development. Unpublished technical report. Edinburgh: RMP Acoustics.