19 Clause 55 provides that a development must meet all the objectives of the clause; and should meet all of the standards of the clause. Of course, a standard such as Standard B10, to the effect that new buildings should be sited and designed to ensure that the energy efficiency of existing dwellings on adjoining lots is not unreasonably reduced, is qualitative in nature and is ultimately a matter of judgment. Other standards, such as B20, are quantitative and can be usually applied without exercising judgment.
20 Contrary to the applicants' submission, on the evidence before me I find that the proposed development does not meet the standard B20 in relation to the rear upper level bedroom adjacent to the study window on the Smith dwelling. In saying this I am relying upon the accuracy of the plans, which I suspect may understate the size of development as built. The plans show a setback of the wall of 2.4 metres; the height of this wall would seem to be about 6.3 metres; and the wall would appear to be opposite north facing windows in the Smith dwelling that are within 3 metres of the boundary. On this basis a setback of 2.62 metres - not 2.4 metres - would appear to be required.
21 In any event I also find that the proposed development is not designed so as to allow "adequate" solar access to the existing north facing habitable room windows in the Smith dwelling. Further, the proposed building is not designed so as to ensure that the energy efficiency of the Smith dwelling is not unreasonably reduced. The Smith residence is designed with its study, kitchen and living area facing north, with substantial north facing windows. There is little doubt that in the colder months of the year this design would reduce the need for heating, provided solar access was not unreasonably blocked. Indeed, Mr Smith produced documents showing that his gas consumption had significantly increased since the construction of the building next door.
22 Significantly, I observe that it would be possible to design a dual occupancy on the subject land - even a large, two level dual occupancy - which reasonably protected the energy efficiency of the Smith dwelling. This could be achieved by concentrating the bulk of any upper level towards the centre of the site in much the same way as the permit requires. As the matter must be approached on the basis that the existing building does not exist, save for taking it into account in assessing the impact it will have if approved, I conclude that the impact of the proposed amendment on solar access to the Smith dwelling could be avoided and should be avoided.
23 I note that a single dwelling may be erected on the subject land without a planning permit. Such a dwelling would be subject to certain performance requirements imposed pursuant to building regulations, these requirements would not include a requirement in relation to solar access similar to standard B10. Hence it is possible that a single dwelling erected on the subject land may significantly reduce solar access to the Smith dwelling, in much the same way as the existing building has this effect upon the living room of the Smith dwelling. This leads me to pose the question: what is the point of refusing permission for two dwellings on the basis that it will adversely affect solar access to the Smith dwelling if much the same impact will result from a development which does not require planning permission? I think the answer to this question is that planning controls in relation to single detached dwellings involve a compromise between protecting the amenity of nearby properties and the certainty and efficiency achieved by allowing single dwellings to be constructed without the need for a planning permit. Thus the fact that a particular detached dwelling may be erected does not mean that the dwelling will achieve acceptable amenity outcomes. Hence the fact that solar access to the Smith dwelling may, or is even likely to, be impaired by the erection of a complying single dwelling does not provide justification for approving two dwellings which would have the same effect.
24 In these circumstances I decline to exercise the discretion available to me to amend the existing dual occupancy permit so as to authorise the as built form of the two dwellings.
25 I should point out that the application before the tribunal does involve certain changes from the as built form of the two dwellings. For example, the front upper bedroom in each dwelling is proposed to be converted to a Queensland style enclosed balcony. Frankly I cannot see any advantage in such a change. The change would have an insignificant impact upon the visual bulk of the building and would look somewhat incongruous in the context of Melbourne's climate. Another change is that the northern garage is proposed to be converted to a carport. Having regard to my views about streetscape issues generally, I see this of no consequence. The southern garage is also proposed to be changed: in this case to a single carport, bordered with a pergola. However I also regard this as of no real consequence. In my opinion, the garage wall, having a height of 3 metres, on the boundary with the Smith property, is not an unreasonable structure. Provided the southern face of the wall is appropriately cleaned or rendered it could be made into an acceptable and appropriate landscape feature within the Smith property. Although it is true that the wall may have some impact upon solar access I do not regard this as unacceptable.
26 Thus the case turns upon the interrelationship between the existing dwelling occupied by Mr and Mrs Smith and the height, extent and setback of the upper level of the dwelling abutting the Smith property. If this could be resolved then it would be appropriate to allow the amendment and the various cosmetic changes proposed by the applicants would be unnecessary. But it can only be resolved in one of two ways. One way is for the upper level of the dwelling abutting the Smith property to be substantially changed; but the applicants have not sought this outcome notwithstanding an opportunity to do so. The other way - and this may be a remote possibility - is that the existing solar access to the windows in the Smith dwelling is no longer required or desired by a new owner of that land. But it would be premature to seek to cross that bridge at this stage.
27 It will thus be necessary to resume the hearing in order to consider the applicants' application to seek approval for plans converting the dwellings into a single dwelling.