Acoustic RB Pty Ltd - Capestone a result of the requirements imposed under Standard Condition 1, an assessment of ... Noise Corridor QDC MP 4.4 ... 1 of QDC MP 4.4 were

30 Heather Street

PO Box 150

Wilston Q 4051

Ph 07 3356 5555

[email protected] ABN 49 129 541 671

Acoustics RB Pty Ltd

20 February 2013 Ref. RB/12-316.R02 Urbex PO Box 197 Wynnum Q 4179 Attention: Mr John Atkinson Dear Sir, Re. Urbex Capestone Estate Stage 2A

Guidance for Purchasers Re Acoustical Design Requirements of QDC MP 4.4 Further to your request, I have prepared a noise model for Capestone Estate Stage 2A. I have then used this model to generate the actual QDC MP 4.4 Noise Categories that will apply to each of the 41 allotments for detached lots as well as for the two large lots of Stage 2A, ie 43 lots total. In addition, I have prepared an outline of (i) three assessment methods, each of which may be adopted to determine the extent of building upgrade to be implemented into the acoustical design of any particular residence, and (ii) the information that is expected to be required by the Building Certifier to allow the certification process to be completed thereafter. 1.0 Background Under the Decision Notice issued by Council for Development Application No 2007/1136/COMB, Council imposed Reconfiguring a Lot Standard Condition 1 to deal with the assessment and control road and rail noise intrusion onto Stage 2A of the Capestone Estate. In essence, this condition placed a requirement on the Applicant to evaluate the extent of road traffic and rail noise intrusion onto the lots of Stage 2A with the objective of identifying “noise affected” lots (ie those lots where the internal noise levels in habitable spaces of the future dwelling to be constructed on the particular lot are expected to exceed the recommended internal sound pressure levels of AS/NZS 2107:2000 Acoustics – Recommended Design Sound Levels and Reverberation Times for Building Interiors) and to provide advice for use by subsequent purchasers regarding the Construction Categories that would apply to the design and construction of the noise-affected dwellings under AS AS3671 - 1989 Acoustics - Road Traffic Noise Intrusion - Building Siting and Construction. An extract from Decision Notice - Development Application No 2007/1136/COMB re-stating Standard Condition 1 is presented in Attachment A.

Capestone Estate Stage 2A – Guidance Re Acoustical Design Requirements of QDC MP 4.4 February 2013

Acoustics RB Pty Ltd RB/12-316.R01 Page 2 of 20

As a result of the requirements imposed under Standard Condition 1, an assessment of the extent of road and rail noise intrusion onto Stage 2A was undertaken in August 2009 by Cardno (Qld) Pty Ltd and duly reported to Council. Cardno Report No 7192/02(002) dated 20 August 2009 refers. Standard Condition 1 made reference to Environmental Protection (Noise) Policy 1997 (EPP-N 97). Since the time of the imposition of this condition, however, EPP-N 97 has been repealed and replaced by Environmental Protection (Noise) Policy 2008. In addition, since August 2009 when Cardno Report No 7192/02(002) was prepared, QDC MP 4.4 Buildings in a Transport Noise Corridor has been gazetted. The significant effect of these changes is that the previously imposed requirement to use the Construction Categories of AS3671 - 1989 has been largely superseded by the noise level assessment regime of QDC MP 4.4. In view of these changes, it is now necessary to update the earlier noise level assessment process based on the application of Construction Categories to one based on the requirements of QDC MP 4.4. 2.0 Application of QDC MP 4.4 Buildings in a Transport Noise Corridor QDC MP 4.4 Buildings in a Transport Noise Corridor was gazetted on September 2010. The stated

purpose of QDC MP 4.4 is “to ensure habitable rooms of Class 1, 2, 3 and 4 buildings located in a Transport Noise Corridor are designed and constructed to reduce transport noise.” Under the provisions of Section 246Z of Building Act 1975, it is understood that a Transport Noise Corridor (TNC) has been designated along both sides of the Redcliffe Rail Line. Based on current projections of rail traffic volumes on the line, it is expected that the TNC designation would apply to all land lying within 250m of the rail corridor. A Transport Noise Corridor has not been declared for land adjoining Capestone Boulevard. In general, all residential allotments located within a TNC will need to be acoustically designed in accordance with the requirements of QDC MP 4.4 having regard to the relevant noise categories. The noise categories can be determined by reference to the DHPW website or in accordance with the alternative site-specific noise level assessment method. QDC MP 4.4 also permits building upgrade requirements to be determined either (i) by application of noise categories determined from the DHPW website, or (ii) from the results of the alternative site-specific noise assessment. When applying the noise assessment method to the determination of either the noise categories or the building upgrade requirements that apply to any specific residence located within a TNC, due consideration may be given to the following matters:- 1. Site topography.

2. Beneficial shielding provided by any barriers – either existing or required to be constructed as a condition of the approval of the Development Application over the subject site.

3. Acoustical shielding provided by existing and approved buildings, where “approved buildings” refers to (i) buildings for which formal building approval has been granted, or (ii) in the case of the specific building/s being assessed, where building approval is being sought.



In addition, and as a result of additional advice provided by DTMR relating primarily to control of road traffic noise intrusion and, by extension, to the control of rail noise intrusion, the following refinements to the noise assessment method are also applicable:- 4. Advice from DTMR in November 2011 contends that determination of the relevant noise

category may be made on a facade-specific basis, ie the noise categories that apply to any specific residence may differ from one facade to the next due to the effect of shielding by the residence itself or by other nearby residences.

5. In January 2012, DTMR refined their earlier advice to allow a more reasonable and practical approach to be adopted in the determination of the site-specific noise categories. In essence, this amended advice contends that, where building floor plans have been prepared for a residence and the acoustical design of the residence is being undertaken, facade-specific noise categories may be determined for each habitable space individually rather than on a whole-of-facade basis. For example, if the facade of a residence is subjected to two noise categories, the higher of the two noise categories need apply only to the spaces exposed to the higher category, not to all spaces exposed to that facade of the dwelling.

6. More recently in April 2012, updated advice from DTMR has resulted in further refinement of the acoustical design procedures. This updated advice contends that in situations where noise contours can be plotted at fine gradation around the external facades of the building being assessed, such that noise levels can be determined with precision at individual building facade elements, the calculation procedures of AS3671 - 1989 Acoustics - Road Traffic Noise Intrusion - Building Siting and Construction may be adopted in lieu of the noise categories and the minimum Rw values presented in Schedule 1 of QDC MP 4.4 to determine the precise level of building upgrade required to be implemented to achieve compliance with the internal sound level of AS/NZS 2107:2000 Acoustics – Recommended Design Sound Levels and Reverberation Times for Building Interiors1 that is applicable to the specific space.

Note: AS3671 – 1989, as its name suggests, provides guidance on dealing with road traffic noise intrusion. There is currently no equivalent standard to deal with rail noise intrusion into habitable spaces. Notwithstanding, even though AS3671 – 1989 is not directly applicable to the control of rail noise intrusion, it can be demonstrated that it is a relatively simple matter to apply standard acoustical theory and calculation techniques to the processes of AS3671 – 1989 to yield acceptable outcomes.

1 The minimum Rw values presented in Schedule 1 of QDC MP 4.4 were determined for a generic building design by applying the

calculation techniques of AS3671 – 1989 to achieve compliance with the satisfactory internal sound levels of AS/NZS 2107:2000. Refer tabulation of Referenced Documents of QDC MP 4.4. Because it was necessary to cover a moderately wide range of functional variances for each particular space (ie number of exposed facades, floor areas, areas of glazing, ceiling height, presence of roof/ceiling construction, presence of entry door, et cetera) in doing so, as well as deal with (i) a 5dBA spread of noise levels within each Noise Category and (ii) generalised (and usually conservative) offsets between (a) L10(18hour) and LAeq,1hrnight values and (b) L10(18hour) and LAeq,1hrday

values, a significant degree of conservatism was built into the minimum Rw values of Schedule 1 of the QDC.

In addition, the minimum Rw values of Schedule 1 have been determined on the basis that equal levels of acoustic energy are transmitted via each of the specific building elements. In practice, the acoustical performance of wall and roof/ceiling constructions, even under “standard construction” conditions, often exceeds the minimum Rw values of Schedule 1. As a result of this, a re-balancing of the Rw performance requirement for glazing can be undertaken without increasing the level of noise intrusion and without jeopardising compliance with the relevant internal sound levels of AS/NZS 2107:2000.

When due consideration is also given to the actual level of noise exposure at the facade, rather than adoption of the applicable 5dBA Noise Category band, a further refinement of the Rw performance requirement for glazing can be conducted, again without jeopardising compliance with the relevant internal sound level requirement. As a result, when these refinements are adopted, it has been determined that, in almost all instances, the glazing to habitable spaces will not need to be upgraded to the degree stated in Schedule 1. Furthermore and in particular, for spaces with relatively low areas of glazing and exposed to noise levels at or around 63dBA, it has been determined routinely that full compliance with the relevant internal sound levels of AS/NZS 2107:2000 can be achieved without requiring any upgrade being made to the acoustic performance of the glazing beyond standard construction.



3.0 Default Noise Categories as Advised by DHPW Website At present, the Transport Noise Corridor Search Tool on the DHPW website is unable to provide a response to searches conducted for lots over Stage 2A. Notwithstanding, it is expected that the deemed-to-apply Noise Category designations under QDC MP 4.4 would be generally as shown in Table 1.

Noise Category Expected Offset Distance from Common Boundary with Rail Reserve (m)

4 0-25

3 25-75

2 75-135

1 135-250

0 NA

Table 1 – Expected Default Noise Categories by Offset Distance from Rail Reserve

Having regard to the information presented in Table 1, it can be determined that Lot 112 would lie solely in the Noise Category 4 band while Lots 99-111 would be expected to lie in both the Noise Category 3 and Noise Category 4 bands and Lots 113, 114, 123 and 127 are likely to located in Noise Category 3 band only. Similarly, Lots 115, 124-126, 142-145 and 209 would be expected to lie in both the Noise Category 2 and Noise Category 3 bands, while Lots 116-122, 128 and 129 are likely be situated in the Noise Category 2 band only. The remainder of the lots, ie Lots 130-134, are likely to lie in the Noise Category 2 and Noise Category 1 bands, or in the Noise Category 1 band only. Note: As indicated above, many of the lots of Stage 2A would be expected to be subjected to more than one default noise category. Under QDC MP 4.4, where a lot is designated as lying in more than one noise category band such that two or more noise categories would apply to the residence (ie two or noise categories encroach onto the building location envelope for the particular lot), the higher of the two noise categories is deemed to apply to the residence to be constructed on the lot. For example, Lot 100 is expected to be located within both the Noise Category 4 and Noise Category 3 bands. The default category for Lot 100 would be Noise Category 4. Similarly, Lot 125 is anticipated to be located within both the Noise Category 3 and Noise Category 2 bands. The default category for Lot 125 would be Noise Category 3.



4.0 Refined Noise Categories 4.1 Assumptions Having regard to each of Matters 1-3 above, the noise model for Stage 2A of the Capestone Estate has been configured to generate the QDC MP 4.4 Noise Categories that will apply as a result of rail noise intrusion onto each of the 43 lots of Stage 2A under the Noise Assessment provisions of QDC MP 4.4. In each case, due account has been taken of the site topography (including the site earthworks levels) and the still-to-be-constructed Capestone Boulevard overpass of the rail corridor. In addition, three further assumptions have been adopted. Firstly, it has been assumed that a 1.8m high acoustic barrier will be erected along the common boundary of Stage 2A with the rail corridor. Notwithstanding the assumptions explicitly stated in Standard Condition 1 and imposed by Council, it is reasonable to expect that, given the disparity between the exigencies of residential development and the demonstrated more measured pace of the planning of the development and construction of the rail line, the rail boundary barrier will constructed by Urbex. Secondly, it is understood that because each of Lots 112-118 adjoining Capestone Boulevard is serviced internally, a 1.8m high rear boundary fence – in this case constructed to acoustic fence standard – will be constructed by Urbex along the SW boundary (ie Capestone Boulevard boundary) of each of these seven lots and returned along the NE boundary of Lot 118 as a matter of course. This is notwithstanding Council’s preference under the Local Area Plan for there to be no barriers along boundaries with Council-controlled roads2. Thirdly, because Council’s original requirements for control of noise intrusion stated in Standard Condition 1 extended to both road and rail noise intrusion, but the provisions of the QDC apply only to rail noise intrusion, it is necessary to ensure that noise level assessment regime developed to replace the Construction Category method takes due account of the need to address road traffic noise intrusion as well as rail noise intrusion. To this end, and giving due regard to the requirement to ensure that the noise level assessment process is straight-forward, fair and practical so that it can be readily and reliably implemented, it has been concluded that these objectives would be best served by simply applying the Noise Category determination procedures of QDC MP4.4 directly to the assessment of the extent of noise intrusion from road traffic on Capestone Boulevard as well. While doing so will result in a more conservative determination of the significance of road traffic noise intrusion onto Stage 2A, the consequences of this adopting this assumption are not of great significance. This is for two reasons. In the first instance, only four of the 41 lots for detached residences are expected to be exposed to road traffic noise levels of sufficient magnitude to warrant upgrade and, even then, only if highset residences are constructed on these four lots and, in such event, any building upgrade requirements would apply only the upper level facades of the highset residence.

2 The constraint on the erection of noise barriers to Council-controlled roads as described in the Local area Plan and as reflected

accordingly in Standard Condition 1, can be reasonably applied to lots with direct access from the specific Council road, eg Capestone Boulevard, but it is not a reasonable requirement to impose such restrictions in situations where the same lots are serviced by an internal road and the requirement to erect a standard height 1.8m boundary fence to delineate the property as well as to provide security and safety of the residents would over-ride any aesthetic predilections or sensitivities of Council.



Secondly, the dominant source of noise intrusion onto the site will be rail movements along the rail line which, in turn, will mean that the acoustical design of residences will be clearly driven by the requirements to control rail noise intrusion, not the necessity to control road traffic noise intrusion. On almost all affected lots, the design upgrades to be implemented into the design of the residence to control rail noise intrusion will also adequately deal with the intrusion of road traffic on Capestone Boulevard. In view of this, the analysis that follows below presents a schedule of lots affected by noise intrusion together with a determination of the QDC MP 4.4 Noise Category/s that would apply to residential construction on the specific lot. To assist the subsequent acoustical design review process for residences on affected lots, the prime source of noise intrusion (ie rail in almost all instances, or road for a small number of lots) has also been stated. In this way, the subsequent acoustical analysis can be focused on controlling the noise intrusion from the dominant noise source using the acoustical calculation and design methods appropriate to controlling noise from the specific source. 4.2 Prediction Methodology The prediction of rail traffic noise intrusion onto the site has been conducted using the Kilde 130 noise level prediction algorithms endorsed by Queensland Rail and as applied by the SoundPLAN computer program. The inputs into the Kilde 130 rail noise model have been derived from information provided by QR with respect to train type, acoustic source height for each type of train, train length, train speeds and source noise levels (both LAmax and SEL) for the relevant type of train and locomotive when measured at 25m. In addition, due regard has been given to the expected number of daily passbys of each train type along the Redcliffe Rail Line. The rail noise model was configured to predict both LAeq,24hr and LAmax passby noise levels. As required by the QDC, the facade-corrected LAmax passby

3 noise levels were used as the basis of determining the extent of rail noise intrusion. The same SoundPLAN computer model was re-configured to calculate the extent of road noise intrusion using the CRTN ’88 noise level prediction algorithms endorsed by DTMR and Council. As required by QDC MP 4.4, the facade-corrected L10(18hour) noise levels were used as the basis of determining the extent of road traffic noise intrusion. For both noise models, due account was also taken of the site topography and the beneficial shielding provided by the barriers discussed above in Section 4.1. In addition, it has been assumed that (i) a safety guard rail will be constructed on both sides of the approach to the Capestone Boulevard overpass and (ii) concrete New Jersey kerb safety barriers will be constructed on the overpass itself.

3 Notwithstanding the slight differences in definition between LAmax passby as applied by SoundPLAN and Single Event Maximum Noise

Level is designated by QR, for the purposes of assessment against the requirements of QDC MP 4.4, both metrics can be considered to be interchangeable.



4.3 Noise Control Plots A set of four noise contour plots has been prepared. The noise contour plots are described below:- Figure 1: Rail Traffic Noise Categories for the lower facades of residences

Figure 2: Road Traffic Noise Categories for the lower facades of residences

Figure 3: Rail Traffic Noise Categories for upper level facades of highset residences

Figure 4: Road Traffic Noise Categories for upper level facades of highset residences These figures are attached. Having regard to the (i) the information presented in each of Figures 1 and 2 and (ii) standard side and front setback distances and normally adopted rear setbacks, the actual noise categories that would apply to the lower facades of residences on each of the 43 lots of Stage 2A can be determined directly. The results are presented in Table 2. Similarly, having regard to the information presented in each of Figures 3 and 4 and the same assumptions regarding setbacks, the actual noise categories that would apply to the upper level facades of residences on each of the 43 lots of Stage 2A can be determined in the same manner. The results are presented in Table 3. Note: For the 41 lots for detached residences designated as lying in more than one noise category band, the higher of the two noise categories has been applied to the lot. Having regard to 15m building setback distances expected to apply to Lots 99-112 adjoining the rail corridor, however, it is possible to further refine the Noise Categories for these 14 lots. Given the large area of each of the two large lots (ie Lots 807 and 809) each of which has been determined as lying in more than one noise category band, both noise categories have been identified in the following tables.

Lot No Noise

Category

Dominant Noise

Source Lot No

Noise Category

Dominant Noise

Source Lot No

Noise Category

Dominant Noise

Source

99 2 Rail 114 1 Rail 129 1 Rail

100 2 Rail 115 1 Rail 130 0 Rail

101 2 Rail 116 1 Rail 131 0 Rail

102 2 Rail 117 1 Rail 132 0 Rail

103 3 Rail 118 1 Road 133 0 Rail

104 3 Rail 119 0 Rail 134 0 Rail

105 3 Rail 120 0 Rail 142 1 Rail

106 3 Rail 121 1 Rail 143 1 Rail

107 3 Rail 122 1 Rail 144 1 Rail

108 3 Rail 123 1 Rail 145 1 Rail

109 3 Rail 124 1 Rail 209 1 Rail

110 3 Rail 125 1 Rail 807 0 & 1 Rail

111 3 Rail 126 1 Rail 809 0 & 1 Rail

112 4 Rail 127 1 Rail

113 2 Rail 128 1 Rail

Table 2 – Actual Noise Categories by Lot – Lower Facades of Residences



Lot No Noise

Category

Dominant Noise

Source Lot No

Noise Category

Dominant Noise

Source Lot No

Noise Category

Dominant Noise

Source

99 4 Rail 114 2 Rail 129 1 Rail

100 4 Rail 115 2 Rail 130 0 Rail

101 4 Rail 116 2 Road 131 0 Rail

102 4 Rail 117 2 Road 132 0 Rail

103 4 Rail 118 2 Road 133 0 Rail

104 4 Rail 119 1 Rail 134 0 Rail

105 4 Rail 120 1 Rail 142 1 Rail

106 4 Rail 121 1 Rail 143 1 Rail

107 4 Rail 122 1 Rail 144 1 Rail

108 4 Rail 123 2 Rail 145 1 Rail

109 4 Rail 124 2 Rail 209 1 Rail

110 4 Rail 125 2 Rail 807 0 & 1 Rail

111 4 Rail 126 2 Rail 809 0 & 1 Rail

112 4 Rail 127 2 Rail

113 3 Rail 128 1 Rail

Table 3 – Actual Noise Categories by Lot – Upper Level Facades of Highset Residences Note: The Noise Category determinations presented above in Tables 2 and 3 have been derived directly from the noise contour plots presented in Figures 1-4 and in accordance with the advice from DTMR as outlined in Section 2.0 above and Attachment B following. These noise categories may be used to guide the acoustic design of residences to be constructed on any of the lots of Stage 2A. Refer also Simple Method outlined in Section 5.1 following. Over time, however, as residences are constructed on the site, the presence of approved residences close to the rail corridor and Capestone Boulevard will provide beneficial shielding to residences to be constructed on lots further removed from the rail line and the road. In turn, this will tend to reduce the specific noise category that will apply to some of the further-removed lots. In particular, it is likely that the presence of approved residences close to the rail corridor will result in a reduction of the noise categories that will apply to lowset residences constructed on some lots (particularly Lots 113, 114, 123-129, 142-144 and 209). Refer also Refined Methods 1 and 2 outlined in Section 5.1 following.



5.0 Guidance Re Acoustical Design and Certification Process 5.1 Determination of Noise Categories for a Specific Residence By reference to Tables 2 and 3, it can be seen that if due regard is given to site topography as well as the beneficial shielding provided by (i) the 1.8m high barrier to be erected along the common boundary with the rail reserve and (ii) the 1.8m high barrier to be erected along the SW boundary of each of Lots 112-118 and returned along the NE boundary of Lot 118, the actual noise categories applying the 43 lots of Stage 2A will be substantially lower than the default noise categories derived from Table 1 above. For lowset residences and the lower levels of any highset residences, reductions of at least one and, possibly, two noise category ratings would be expected to accrue. Having determined the noise categories for each lot, the extent of building upgrade that will be required to be implemented for a specific residence on any particular lot can be determined by one of three methods as discussed below:- 1. Simple Method:

Having regard to Considerations 1-3 of Section 2.0 above, refer to Tables 2 and 3 to determine the actual noise category for each level of the residence. By reference to Schedules 1 and 2 of QDC MP 4.4, select the deemed-to-comply building constructions. Refer also Section 5.2.1.

2. Refined Method 1:

Having regard to Considerations 1-5 of Section 2.0, update the existing noise model to include the specific residence to be constructed on the particular lot and, taking account of the beneficial shielding provided by (i) other already-constructed "approved" residences on Stages 1, 2 and 3 and (ii) the residence to be constructed on the particular lot itself, determine the noise category/s applicable to each facade of each habitable space within the residence. For most habitable spaces of any residence, this method will result in noise categories that are lower than those determined by the Simple Method above.

Thereafter, design the residence in accordance with the schedules of QDC MP 4.4. The reduction in the noise category ratings relative to both the default noise categories and the noise categories determined by the Simple Method, will result in substantial reductions in building costs. Refer also Section 5.2.1.

3. Refined Method 2:

Having regard to Considerations 1-6 of Section 2.0, update the existing noise model to include the specific residence to be constructed on the specific lot and, taking account of the beneficial shielding provided by (i) other already-constructed "approved" residences on Stages 1, 2 and 3 and (ii) the residence to be constructed on the specific lot, plot noise contours for road or rail noise intrusion, as appropriate, at fine gradation around the external facades of the residence.

Thereafter for each habitable space, apply the calculation procedures of AS3671 - 1989 (either directly for road traffic noise intrusion or modified as necessary for rail noise intrusion as noted in Section 2.0) to determine the precise level of building upgrade (ie the Rw rating of each upgraded building element, or the building construction details for each specific building element to be upgraded) that will be required to be implemented into the design of the dwelling to achieve compliance with the relevant internal sound level of AS/NZS 2107:2000.

Note: The added precision resulting from the adoption of the calculation procedures of AS3671 - 1989 (either directly or appropriately modified) will result in significant reductions in building costs relative to Refined Method 1 and even more significant reductions relative to the Simple Method. Refer also Section 5.2.2.



5.2 Building Design Upgrade Procedure Requirements 5.2.1 Simple Method and Refined Method 1 Only Once the noise category/s for a specific residence have been determined by either the Simple Method or Refined Method 1, and having regard to the provisions of QDC MP 4.4, the extent of building upgrade required to be applied to each habitable space of a residence, should be established in the following manner:- 1. Schedule 1 of QDC MP 4.4 should be used to determine the Rw performance requirements (ie

the acoustical ratings) for each facade element for each specific noise category, and

2. Then, Schedule 2 of QDC MP 4.4 should be used to determine the deemed-to-comply building constructions, ie the "acceptable forms of construction", that match the Rw performance requirements. As permitted under the provisions of QDC MP 4.4, however, building constructions other than the deemed-to-comply constructions presented in Schedule 2 may be incorporated into the building design provided that, in each case, the building construction “achieves the minimum Rw value for the relevant building component and applicable noise category.”

Thereafter, to ensure that the residence is constructed in accordance with the required building upgrades, the building design drawings should be annotated to include (i) reference to the Rw ratings for specific building facade elements (eg windows) which are then to be used as a specification for supply of these facade elements, (ii) the specific deemed-to-comply constructions presented in Schedule 2 for the particular building facade element (eg external walls), or (iii) in the case of other building elements where none of the specific deemed-to-comply constructions is to be incorporated into the building design (eg in the case of lightweight external wall constructions), an alternative building construction that “achieves the minimum Rw value for the relevant building component and applicable Noise Category4.”

5.2.2 Refined Method 2 Only Once the schedule of (i) Rw ratings for each upgraded building element and/or (ii) the building construction details for each specific building element to be upgraded has been prepared as outlined above in Section 5.1, annotate the building design drawings to include to these specific Rw ratings and/or (ii) the building construction details.

4 In instances where alternative building constructions are proposed, it would be prudent to ensure that confirmation that the specific

construction achieves the required minimum Rw rating required is provided either by the facade elements supplier or by an RPEQ-registered acoustical engineer experienced in acoustical design.



5.3 Documentation for Building Acoustical Design Certification Certification of the adequacy of the acoustical design of the residence is a matter for sole determination by the Building Certifier. To assist the Building Certifier in making this determination, it is to be expected that various documents will need to be supplied to the Certifier. The documentary requirements of the Building Certifier should be determined by making a request of the Certifier accordingly. While the requirements of individual Building Certifiers will vary from one to another, it is likely that the following information will need to be provided in any event:-

Simple Method: (i) A copy of this letter of guidance

(ii) Building design drawings annotated to include (a) the noise category applying to each level of the dwelling and (b) reference to the Rw ratings, specific deemed-to-comply constructions and alternative building construction/s (plus supporting confirmation that the alternative construction/s comply with the Rw rating required) as discussed above in Section 5.2.1.

Refined Method 1: (i) A copy of this letter of guidance

(ii) An acoustical design review report for the specific residence detailing the noise categories applicable to each facade of each habitable space within the residence and, if requested, a schedule of additional annotations to be added to building design drawings.

(ii) A completed Form 15 Compliance Certificate for Building Design or Specification to accompany the acoustic design review report.

(iv) Building design drawings annotated to include (a) the noise category applying to each habitable space of the dwelling and (b) reference to the Rw ratings, specific deemed-to-comply constructions and alternative building construction (plus supporting confirmation that the alternative construction complies with the Rw rating required) as also discussed in Section 5.2.1 above.

Refined Method 2: (i) A copy of this letter of guidance

(ii) An acoustical design review report for the specific residence listing (a) the Rw ratings for each upgraded building element and/or (b) the building construction details for each specific building element to be upgraded.

(ii) A completed Form 15 Compliance Certificate for Building Design or Specification to accompany the acoustic design review report.

(iv) Building design drawings annotated to include (a) Rw ratings for each upgraded building element and/or (b) the building construction details for each specific building element to be upgraded as discussed above in Section 5.2.2.



As also discussed above, the actual noise categories for lowset residences and the lower levels of any highset residences, will be at least one noise category rating and, possibly, two noise category ratings lower than the default noise categories that would be expected to apply. This reduction will result in lower building costs across-the-board. Furthermore, Refined Method 1 will result in further reductions in the noise categories for individual habitable spaces and, consequently, further reductions in building costs. Ultimately, however, the greatest savings in building costs will accrue when Refined Method 2 is adopted. I trust that this information is adequate for your purposes at this stage, but should you require any further information, please do not hesitate to contact me. Yours faithfully, Acoustics RB Pty Ltd

Russell Brown RPEQ 2799



Figures 1-4

Capestone Estate Stage 2 – Guidance Re Acoustical Design Requirements of QDC MP 4.4 February 2013


Attachment A

Extract from Decision Notice - Development Application No 2007/1136/COMB

Reconfiguring a Lot - Standard Condition 1

Several lots within this development may be subjected to long term external noise levels greater than the long term acoustic quality objective for "noise-sensitive receptors', such as dwellings, under the Environmental Protection Act 1994. Within the Northern Growth Corridor (NGC), Council has determined that traffic and other transport infrastructure noise reduction measures are to be achieved by appropriate building construction rather than by the use of noise attenuation barriers on the Mango Hill Ring Road (refer to the Mango Hill Local Area Plan). The developer shall prepare an acoustic report for identifying all lots that may be subject to environmental nuisance or environmental harm in accordance with the Environmental Protection Act 1997 and the Environmental Protection (Noise) 1997 (EPP Noise). The acoustic report is to identify 'noise affected' lots (lots where the noise levels exceed those recommended in AS/NZS 2107:2000) and provide advice regarding the Construction Category under AS 3671:1989 for the 'noise affected' residential lots. The acoustic report shall be based on the following parameters:

Assume State transport infrastructure (road and rail) includes noise attenuation to achieve the planning levels given in Schedule 1 of the EPP Noise (this does not limit the relevant State agency from requiring noise reports and attenuation measures to be provided by the developer);

Assume the future North South Urban Arterial Road includes noise attenuation to achieve the planning levels given for a State-controlled road in Schedule 1 of the EPP Noise;

No noise attenuation is included in other public (Council) roads as this is to be achieved by appropriate residential construction rather than by the use of noise attenuation barriers (refer relevant Local Area Plan);

Achieving the recommended design sound levels given in AS 2107:2000. The acoustic report is to be submitted to and approved by the Council's Delegated Officer prior to the approval operational works for this stage of development. Where residential lots are identified as 'noise affected', it is mandatory that the landowner incorporate noise attenuation measures into the dwelling design and construction to meet the requirements of the AS/NZS 2107:2000. The following property note shall be placed on Council's property note system for each lot assessed as Construction Category 2 under AS 3671:1989: "The predicted long term noise levels over this lot generated by future traffic and transport infrastructure in the area will exceed recommended levels. To ensure that noise levels within the dwelling meet the recommended noise levels under Australian Standard AS2107:2000 noise attenuation measures (Category 2 construction under Australian Standard AS 3671:1989) must be incorporated into the budding design and construction. Prior to occupation of the new dwelling the land owner is required to provide written evidence to Council's Development Services Department that this requirement has been satisfied."



The following property note shall be placed on Council's property note system for each lot assessed as Construction Category 3 under AS 3671:1989: "The predicted long term noise levels over this lot generated by future traffic and transport infrastructure in the area will exceed recommended levels. To ensure that noise levels within the dwelling meet the recommended noise levels under Australian Standard AS2107:2000 noise attenuation measures (Category 3 construction under Australian Standard AS 3671:1989) must be incorporated into the building design and construction. Prior to occupation of the new dwelling the land owner is required to provide written evidence to Council's Development Services Department that this requirement has been satisfied." The following property note shall be placed on Council's property note system for each lot assessed as Construction Category 4 under AS 3671:1989: "The predicted long term noise levels over this lot generated by future traffic and transport infrastructure in the area will exceed recommended levels. To ensure that noise levels within the dwelling meet the recommended noise levels under Australian Standard AS2107:2000 noise attenuation measures (Category 4 construction under Australian Standard AS 3671:1989) must be incorporated into the building design and construction. Prior to occupation of the new dwelling the land owner is required to provide written evidence to Council's Development Services Department that this requirement has been satisfied."



Attachment B Refinement of QDC MP 4.4 Noise Categories Table 1 of QDC MP 4.4 sets Noise Categories depending upon the external noise level to which the dwellings subjected when measured 1m from the facade of the proposed or existing building5. The noise category levels of Table B1 are reproduced below.

Noise Category State-Controlled Roads and Designated Local Government

Roads, L10(18hour) (dBA)

Railway Land

Single Event Maximum Noise Level, LAmax passby (dBA)

Category 4 ≥ 73 dBA ≥ 85 dBA

Category 3 68 - 72 dBA 80 - 84 dBA



Category 0 ≤ 57 dBA ≤ 69 dBA

Table B1 – Noise Category Levels Reproduced from QDC MP 4.4

Note: Recognising the discontinuities and resultant practical uncertainties evident in the noise level class intervals ascribed by Table B16, DTMR has issued a recent directive requiring that, in the case of State-controlled roads, the class intervals be adjusted. The new class intervals for road traffic noise are presented in Table B2 together with, for consistency, the class intervals for rail noise reconciled in the same manner. The Single Event Maximum Noise Levels presented in Table 2 for each Noise Category have been adopted and applied accordingly.

Noise Category State-Controlled Roads and Designated Local Government

Roads, L10(18hour) (dBA)

Railway Land

Single Event Maximum Noise Level, LAmax passby (dBA)

Category 4 ≥ 73 dBA ≥ 85 dBA

Category 3 68-73 dBA 80-85 dBA



Category 0 ≤ 58 dBA ≤ 70 dBA

Table B2 – Corrected Noise Category - QDC MP 4.4

5 in contrast to other Codes and Guidelines, QDC MP 4.4 permits assessment of extent of road and rail noise intrusion onto the site to

take account of shielding provided by existing and approved buildings, only where “approved buildings” refers to (i) buildings for which formal building approval has been granted, or (ii) in the case of the specific building being assessed, where building approval is being sought. It does not allow the shielding of other future residences to be taken into account when determining the extent of noise intrusion to lots located one or two rows of lots distant from transport noise source.

6 The discontinuities are the gaps between the upper bound of one Noise Category and the lower bound of the next higher Noise

Category. Discontinuities give rise to resultant practical uncertainties. For example, should the residence subjected to an external noise level of 62.5dBA L10(18hour) be ascribed a Noise Category 1 designation or a Noise Category 2 designation? To resolve this uncertainty, the upper bound of one Noise Category must be equivalent to the lower bound of the next higher Noise Category. The corrected Noise Categories are presented in Table B2.