Goal: To create an aesthetically pleasing and calming environment, which encourages guests to feel relaxed and comfortable so that they enjoy their stay and are more apt to return. To minimize noise from other guest rooms, the corridor and mechanical equipment.
- There are several issues that must be addressed concerning acoustics in a hotel project. These issues stem from the two types of sound that must be controlled: airborne sound and impact sound. A typical airborne sound is music or talking. A typical impact sound is the footfall sound of an upstairs guest.
- There are two rating systems that compare the acoustic quality of various building assemblies. Both classify acoustical performance with a single number. In both cases, the higher the number, the better the sound isolation performance. Sound Transmission Class (STC) rates a partition's resistance to airborne sound transfer.
- The Uniform Building Code (UBC) contains requirements for sound isolation between dwelling units in Group R occupancy project (including hotels). However, these criteria are not universally enforced. UBC requires walls and floor/ceiling assemblies to have an STC rating of 50. The code also requires that floor/ceiling assemblies have an Impact Insulation Class rating of 50. *NOTE: Even if a particular municipality has not adopted this part of the code, it is still recognized as an industry standard minimum.
- Resilient channel can be used to help improve the isolation quality of a wall. However, if artwork and/or headboards are mounted against the wall (as is often the case in a hotel), the effectiveness will be greatly diminished. Consider increasing the isolation through some other means (i.e., increased mass, increased air space, double or staggered stud walls, etc
- All air-gaps and penetrations must be carefully controlled and sealed. Even a small air-gap can degrade the isolation integrity of an assembly.
- The perimeter of the wall and any penetration must be sealed air-tight with a non-hardening acoustic sealant.
- Avoid the installation of back-to-back penetrations (outlets, light switches, and phone jacks). Consider installing a putty pad to the back of all outlets in party walls.
- Ideally, elevator shaft footings, floor pads, masonry shaft walls, elevator equipment mountings, etc. should be totally isolated from the building structure. Structure borne noise/vibration from elevator operation may be extremely annoying. Additionally, any penetration or air gap in or around the wall must be sealed airtight with a non-hardening acoustic sealant.
- The building code (UBC) specifies that the entrance doors from interior corridors shall have an STC rating of 26 or higher. The higher the STC rating of the doors, the better the isolation. However, if the seal around and under the door is not maintained, selecting a high rated door is meaningless. Ideally, drop seals that seal to a threshold (not carpet) can be installed. An acoustically absorptive ceiling and carpet in the corridor will help to control the noise levels within the corridor.
- The majority of noise concerns can be alleviated through proper space planning. Sensitive areas should not be located near potentially noisy areas. Potentially annoying sound transmission from floor to floor (for example, from a restroom or laundry facility above a bedroom) can be mitigated through the vertical mirror of spaces. Potentially noisy areas (such as elevators, vending rooms and laundry facilities) should not be adjacent to guest rooms.
- Although the building code does not address plumbing noise, this issue can be a major source of noise complaints. Plumbing noise can be both airborne and structure borne. To reduce plumbing noise, pipes should be resiliently mounted, that is, adequately insulated from their supports. To further reduce plumbing noise, the pipes should be wrapped with pipe lagging material.
- Any roof-mounted equipment should be analyzed for potential noise/vibration impact.
- Consider the exterior noise impact to the guest rooms (such as a nearby airport or freeway). The majority of this noise is transmitted through the windows and P-Tac units. Upgrading these elements might be necessary.
- Noise Criteria (NC) ratings can be used to specify the allowable background noise levels (not including activity noise from the occupants) within a given space. Recommended NC levels vary depending on the type of space and the listening requirements. The recommended NC level for a bedroom is NC 20-30. Most hotel air-conditioning systems produce noise levels well in excess of the recommendation. Additionally, HVAC noise can act as a masking system in hotel projects, raising the background noise level and thus reducing the awareness of transmitted noise. (NOTE: Obviously, this benefit only occurs when the system is on.) The equipment noise should not exceed NC 25-30 and the air noise of the HVAC system should not exceed NC 35.