Approved report

4 C D Developments
Environmental Traffic and Rail Noise Level Impact Assessment for Proposed Residential Unit Development,
54 Elm Street and 5 Pearl Street, Cooroy                                                                    Page 19 of 35



The 1.5 metre high acoustic barrier is required along the total length of the Elm Street boundary, with
returns 15 metres long and 1.5 metres high. Figure 7 details the location of these acoustic barriers.
These acoustic barriers must be designed and constructed in accordance with MRTS 15. With respect
to Figure 7 the notation for the corner of each Lot with an acoustic barrier and for each change in
direction of a Lot boundary with an acoustic barrier, the numbers represent base of acoustic barrier/top
of acoustic barrier RL AHD.

Further to the above, to assist in minimising the required Rw ratings for the materials of construction, a
2.0 metre high acoustic barrier compliant with MRTS 15 will be constructed in lieu of the required
minimum 1.5 metre high acoustic barrier, in exactly the same location as the 1.5 metre high acoustic
barrier. This is reflected in Figure 7.


                      2.0m High            106.4/108.4
                       Acoustic                 4
                        Barrier
   107.0/109.0



                       107.0/109.0




      2.0m High
       Acoustic
        Barrier

                                                 106.5/108.5

                        107.4/109.4




                               2.0m High
        107.4/109.4             Acoustic
                                 Barrier




                                                   Figure 7
                        Location and Heights of Acoustic Barriers (Top of the Page North)


Traffic Noise – Level 2 Facade

As the LA90,8H was less than 40 dB(A) the facade traffic noise limit is 60 dB(A) LA10,18H facade corrected.

For traffic noise control to the closest Level 2 facade to Elm Street, with due consideration of the 1.4
metre deep cut, by path difference calculation an acoustic barrier 3.5 metres high is required.

With respect to the above barrier height, whilst this is what is required to control ultimate traffic noise
levels to the upper floor (level 2) of the proposed residential unit closest to Elm Street, it is considered
excessive and inappropriate for the surrounding rural/residential setting. Alternatively the upper floor
could have upgraded materials of construction to provide adequate traffic noise to inside habitable




David Moore & Associates Pty Ltd                                                Our reference: R21046/D3569/Rev.0/2.07.21