INTRODUCTION TO ACOUSTICS & SEALS

Helping reduce the amount of sound that passes through a doorway is one of the most common and important applications for door seals. Raven acoustic seals provide an excellent barrier to airborne sound and help ensure that the acoustic attenuation provided by a doorset (the frame and doorleaf along with the seals) is, in many cases, equivalent to the wall or partition into which it is installed.

Raven acoustic seals also help isolate buildings from external noise, for example, from the noise generated from roads, railways and airports and help isolate rooms from airborne noise, for example; from plant and machinery, theatres, cinemas, creches, dental and doctors surgeries, stairwells, passages, interconnected hotel rooms and adjoining apartments.

Approved Document E states a minimum Rw29 is required, Raven acoustic seals meet or exceed this requirement. Raven acoustic seals are widely used internationally in airports, hotels, offices, hospitals, homes and anywhere noise infiltration occurs through doors. Their effectiveness is

best illustrated by the repeated use of Raven acoustic seals by architects, acoustic consultants, door manufacturers, engineers and project builders. The performance of Raven door seals are routinely tested by internationally accredited organisations.

Approved Document E Resistance to the passage of sound

Under the requirements of Approved Document E there are several new and amended regulations that need to be considered in relation to specifying doorsets and acoustic seals. The main points are:

• Requirement E1 Rooms for residential purposes
• Internal walls to achieve 40dB/Rw

• Performance of doorsets. Each separate accommodation unit to achieve resistance to the passage of sound of at least 29dB Rw. All doorsets to incorporate acoustic seals.

• Special acoustic conditions for schools, Building Bulletin 93, these being:

Type of Space used by Students Wall including Glazing Doorset

All spaces except Music Rooms 40 dB/Rw 30 dB/Rw

Music Rooms 45 dB/Rw 35 dB/Rw.

The weighted sound reduction index, Rw of a wall containing a doorset

Example: Office adjoining factory area. Noise at source is 80dB/Rw. Required noise level in office is 40dB/Rw.

Performance of wall & door required is: 80 - 40 = 40dB/Rw.

Criteria for selection of doorset

Establish % of wall area occupied by doorset (assuming the doorset is 10% of partition [40db/Rw]), therefore 29db/Rw doorset will achieve an overall acoustic performance of 37dB/Rw.