ResCode Standards

ResCode Site Coverage and Permeability: Standard B28 for Melbourne Developers

Sammi Lian
Sammi Lian
Principal Architect, ARBV Registered
February 22, 2026 Updated April 24, 202623 min read
ResCode Site Coverage and Permeability: Standard B28 for Melbourne Developers
Key Takeaway

Comprehensive guide to ResCode site coverage and permeability standards for Melbourne developers. Understand B28 requirements, council variations, and strategies to maximise development potential whilst maintaining compliance.

By Sammi Lian, Principal Architect at SQM Architects (ARBV Registration #51498) — over 15 years securing planning approvals for dual occupancy, townhouse, and apartment developments across Melbourne's councils.

Understanding ResCode Standard B28: The Foundation of Site Planning

For property developers in Melbourne’s Eastern Suburbs, site coverage and permeability requirements under ResCode represent fundamental constraints that directly impact development feasibility and project returns. Standard B28 (now renumbered as Standards B2-5 and B5-1 following Amendment VC282 in September 2025) establishes maximum building footprints and minimum permeable surfaces—two metrics that determine how much built form your site can accommodate whilst maintaining stormwater management and neighbourhood character objectives.

Site coverage calculation error checklist for ResCode compliance showing commonly overlooked elements Victoria
Figure 1: Elements commonly overlooked in site coverage calculations

With recent planning reforms introducing deemed-to-comply pathways and removing third-party appeal rights for compliant applications, understanding these standards has become more critical than ever. A development that meets the site coverage and permeability standards achieves automatic compliance with the corresponding objectives, bypassing discretionary assessment and potential objector delays. However, the interaction between these requirements and other ResCode provisions—particularly minimum garden area, tree canopy coverage, and private open space—creates practical constraints that many developers initially overlook during feasibility analysis.

Site area breakdown diagram for 600 square metre dual occupancy showing ResCode garden area and permeability requirements Melbourne
Figure 2: Practical site allocation on 600m² GRZ lot with 30% garden area requirement

This comprehensive guide examines how site coverage and permeability standards operate across Melbourne’s residential zones, the specific variations applied by councils in Whitehorse, Boroondara, Manningham, Monash, Knox, and Maroondah, and the practical strategies that enable developers to maximise built form whilst maintaining compliance. With SQM Architects achieving a 98% planning approval rate across 210+ projects, our experience demonstrates that early consideration of these standards during site selection and concept design directly correlates with project success.

The 2025 ResCode Reforms: What Changed for Site Coverage and Permeability

Amendment VC282 (effective 8 September 2025) fundamentally restructured how site coverage and permeability standards operate within Victoria’s planning system. The reforms introduced a deemed-to-comply framework that removes discretionary assessment where numerical standards are met, whilst simultaneously tightening some requirements and relaxing others based on zone classification.

Standard B2-5 (Site Coverage) now establishes zone-specific maximums that replace the previous uniform 60% threshold. In the General Residential Zone (GRZ)—the predominant zone across Melbourne’s Eastern Suburbs—maximum site coverage increased to 65%, providing developers with an additional 5% building footprint on typical sites. The Neighbourhood Residential Zone (NRZ) maintains 60% maximum coverage, reflecting its lower-density character objectives. The Residential Growth Zone (RGZ) and Mixed Use Zone (MUZ) permit 70% coverage, acknowledging their role in accommodating higher-density development near activity centres and transport corridors.

Site coverage calculations include all buildings, roofed structures (including carports, verandahs, and garden sheds), and any upper-storey projections over ground-floor areas. Eaves up to 600mm, unroofed ground-level terraces, and basement car parking where the roof sits less than 1 metre above natural ground level are excluded from the calculation. This distinction becomes critical when maximising built form—many developers initially overlook covered entry porches, bin store roofs, or upper-storey balcony overhangs in preliminary feasibility assessments, only to discover compliance issues during detailed design.

Standard B5-1 (Permeability) maintains the 20% minimum pervious surface requirement that existed under the previous framework. However, the standard now integrates stricter stormwater management requirements through Water Sensitive Urban Design (WSUD) provisions. Developers must demonstrate that the 20% pervious area effectively manages stormwater runoff, typically requiring a STORM or MUSIC report prepared by a qualified engineer. This represents a shift from simply providing permeable surfaces to proving those surfaces function as intended for stormwater infiltration.

Permeable surfaces include garden beds, lawn areas, and permeable paving systems that meet specific infiltration rates (typically 50mm per hour minimum). Impermeable surfaces include all buildings, sealed driveways, concrete paths, outdoor paved areas, swimming pools, and any sealed surface that prevents water infiltration. The critical distinction: permeable paving must be engineered and certified—simply using pavers on sand is insufficient without demonstrating adequate infiltration capacity.

Zone-Specific Requirements Across Melbourne’s Eastern Suburbs

Understanding which zone applies to your site determines the baseline site coverage and permeability requirements before considering any local variations through zone schedules. The six councils serving Melbourne’s Eastern Suburbs apply these zones differently based on their strategic planning objectives and existing neighbourhood character.

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ResCode site coverage comparison chart showing GRZ NRZ RGZ maximum percentages for Melbourne residential zones
Figure 3: Theoretical vs practical site coverage limits across Melbourne residential zones

General Residential Zone (GRZ) represents the most common zoning across Whitehorse, Boroondara, Manningham, Monash, Knox, and Maroondah. The 65% maximum site coverage provides substantial development capacity, particularly on larger sites where the additional 5% translates to meaningful additional floor area. On a typical 600m² lot, this represents an additional 30m² of building footprint compared to the previous 60% standard—equivalent to an extra bedroom or expanded living area in a dual occupancy development.

However, the interaction between site coverage and minimum garden area requirements creates the practical constraint. Most GRZ schedules across the Eastern Suburbs mandate minimum garden areas between 25% and 35% for lots over 400m². This garden area must be pervious, cannot include buildings or impermeable paving, and must be consolidated rather than fragmented. On a 600m² lot with 30% minimum garden area (180m²), the maximum achievable site coverage becomes 50% (300m²) if the remaining 20% (120m²) comprises driveways, paths, and paved courtyards. The 65% site coverage standard becomes theoretical rather than practical on sites with substantial garden area requirements.

Neighbourhood Residential Zone (NRZ) applies to established residential areas where councils seek to maintain lower-density character. The 60% maximum site coverage reflects this objective, with most NRZ schedules also specifying higher minimum garden areas (often 35-40%) and more restrictive building height limits. City of Boroondara extensively applies NRZ across suburbs including Kew, Hawthorn, and Camberwell, where heritage character and established streetscapes warrant additional protection. Developers should anticipate that NRZ sites offer lower development intensity compared to GRZ equivalents, directly impacting feasibility and potential returns.

Residential Growth Zone (RGZ) applies to areas identified for higher-density development, typically near activity centres, railway stations, and major transport corridors. The 70% maximum site coverage acknowledges the strategic role these locations play in accommodating population growth. However, RGZ sites remain relatively uncommon across the Eastern Suburbs compared to metropolitan Melbourne broadly—most RGZ land concentrates around Box Hill, Glen Waverley, and Ringwood activity centres. The higher site coverage potential must be balanced against increased community expectations for design quality, amenity provision, and neighbourhood integration in these strategic locations.

Council-Specific Variations and Local Requirements

Whilst Amendment VC282 standardised many ResCode provisions, councils retain limited ability to specify local variations through schedules to zones and overlays. Understanding these council-specific requirements proves essential during site selection and concept design, as variations can significantly impact development capacity and project feasibility.

City of Boroondara maintains some of the most restrictive requirements across Melbourne’s Eastern Suburbs, reflecting its emphasis on heritage character and established neighbourhood amenity. Schedule 1 to the NRZ (which applies to most residential areas in Kew, Hawthorn, and Camberwell) specifies 40% minimum garden area for lots over 500m², effectively limiting site coverage to 40% when combined with the 20% permeability requirement. This creates substantial constraints on dual occupancy and townhouse developments, often requiring larger sites (800m²+) to achieve viable project returns.

Boroondara also applies Neighbourhood Character Overlays (NCO) across extensive areas, introducing additional design requirements beyond standard ResCode provisions. Whilst the deemed-to-comply framework removes neighbourhood character as a discretionary assessment criterion, NCO schedules can specify mandatory requirements for building materials, roof forms, front fence heights, and landscaping treatments that must be met regardless of ResCode compliance. Developers should obtain a planning property report early in site assessment to identify any applicable overlays and their specific requirements.

City of Whitehorse generally applies the standard 65% site coverage in the GRZ without additional restrictions through zone schedules. However, Schedule 1 to the GRZ (applying to most residential areas) specifies 30% minimum garden area for lots over 400m², creating the practical constraint discussed earlier. Whitehorse demonstrates relatively consistent application of ResCode standards across different suburbs, with fewer variations compared to Boroondara. This consistency benefits developers by enabling more predictable feasibility analysis and reducing assessment timeframes.

Manningham City Council applies similar requirements to Whitehorse, with 30% minimum garden area in most GRZ areas. However, Manningham’s topography introduces additional considerations—many sites feature significant slope, requiring careful integration of site coverage calculations with cut-and-fill earthworks. The Building Regulations define site coverage based on building footprint at natural ground level, but retaining walls, terracing, and basement construction can impact both site coverage and permeability calculations. Developers should engage civil engineers early when assessing sloping sites to confirm achievable built form.

City of Monash introduces specific requirements for water-sensitive urban design beyond standard permeability provisions. Schedule 1 to the GRZ mandates rainwater tanks (minimum 2,000 litres per dwelling) and requires that at least 50% of driveway areas use permeable paving. These requirements increase construction costs but can be offset against reduced stormwater infrastructure requirements. Monash also specifies that the 20% pervious area must be distributed across the site rather than concentrated in a single location—typically requiring pervious surfaces in front, side, and rear setbacks rather than solely in the rear yard.

Knox City Council applies standard site coverage and permeability requirements without significant local variations. However, Knox extensively uses the Vegetation Protection Overlay (VPO) across residential areas, requiring planning permits to remove, destroy, or lop vegetation. The VPO can impact site coverage calculations where existing trees occupy areas proposed for buildings or hardstand. Developers should commission arborist reports during due diligence to identify protected trees and assess retention feasibility before finalising site acquisition.

Maroondah City Council similarly applies standard requirements with 30% minimum garden area in most GRZ areas. Maroondah’s planning scheme includes specific provisions for sites adjoining public open space or waterways, requiring additional setbacks and landscaping treatments that can reduce effective site coverage. These provisions aim to protect visual amenity from public vantage points and maintain ecological corridors along creek lines. Developers should review planning scheme maps to identify any sites with special landscape or environmental significance before proceeding with acquisition.

Calculating Site Coverage: Practical Examples and Common Errors

Accurate site coverage calculation proves essential for ResCode compliance, yet many developers make errors during preliminary feasibility that only emerge during detailed design or planning permit assessment. Understanding what counts toward site coverage, how to measure building footprints correctly, and which elements receive exemptions prevents costly redesigns and assessment delays.

Site coverage calculation flowchart showing included and excluded elements for ResCode B28 compliance Victoria
Figure 4: What counts toward site coverage under ResCode Standard B2-5

Example 1: Standard Dual Occupancy on 600m² GRZ Site

A typical dual occupancy development on a 600m² lot in the GRZ with 30% minimum garden area demonstrates the practical constraints. Maximum site coverage under Standard B2-5 is 390m² (65%). However, the 30% garden area requirement (180m²) must be pervious and cannot include buildings. If we allocate the minimum 20% permeability (120m²) to garden area, we need an additional 60m² of pervious surface elsewhere on the site—typically in front setbacks or side setbacks with deep soil planting.

This leaves 300m² (50%) available for buildings and impermeable hardstand. If each dwelling requires 150m² building footprint (typical for 3-bedroom townhouses), we’ve consumed the entire 300m² allocation before providing driveways, paths, or paved courtyards. The practical solution: reduce building footprints to 130-140m² each, providing 20-40m² for essential hardstand whilst maintaining garden area and permeability compliance. This demonstrates why the 65% site coverage standard remains largely theoretical on sites with substantial garden area requirements.

Example 2: Small Lot Development in NRZ

A 400m² lot in the NRZ (60% maximum site coverage) with 35% minimum garden area presents even tighter constraints. Maximum site coverage is 240m², but the 140m² garden area requirement plus 80m² minimum permeability (20%) leaves only 180m² for buildings and hardstand. A single dwelling with 120m² footprint, double garage (36m²), and covered entry porch (6m²) totals 162m² site coverage, leaving just 18m² for driveway, paths, and any outdoor paving. This explains why many NRZ sites prove unviable for dual occupancy—the numbers simply don’t work without seeking variations to garden area or site coverage standards.

Common Calculation Errors:

Upper-storey projections: Many developers calculate site coverage based solely on ground-floor footprint, overlooking that any upper-storey projection over the ground floor adds to site coverage. A first-floor bedroom that cantilevers 1 metre beyond the ground floor adds that projection area to total site coverage. Similarly, balconies with roofs above (even if open-sided) count toward site coverage.

Eaves and verandahs: Eaves up to 600mm are exempt from site coverage calculations, but anything beyond 600mm counts. A dwelling with 900mm eaves around the entire perimeter adds significant site coverage—on a 10m x 15m building, the additional 300mm of eaves adds approximately 15m² to site coverage. Covered verandahs and alfresco areas always count toward site coverage regardless of whether they’re enclosed.

Basement car parking: Only basements constructed wholly underground with roofs less than 1 metre above natural ground level are exempt. A basement that projects 1.5 metres above natural ground level counts toward site coverage for the entire basement area. This distinction becomes critical on sloping sites where basement construction may project significantly above ground on the downslope side.

Garden sheds and outbuildings: All roofed structures count toward site coverage, including garden sheds, bin stores, and pool equipment enclosures. A 3m x 3m garden shed (9m²) may seem insignificant but can push a borderline-compliant development into non-compliance. Developers should include all ancillary structures in initial site coverage calculations rather than treating them as afterthoughts.

Permeability Requirements: Beyond the 20% Minimum

Whilst the 20% minimum pervious surface requirement appears straightforward, practical application involves considerations beyond simply providing garden beds. The integration of stormwater management requirements, the distinction between different pervious surface types, and the spatial distribution of permeable areas all impact compliance and development outcomes.

Engineered Permeable Paving Systems:

Many developers seek to use permeable paving to satisfy permeability requirements whilst providing functional hardstand for car parking, driveways, or outdoor living areas. However, not all permeable paving systems qualify for permeability calculations. Standard B5-1 requires that pervious surfaces can absorb water—this necessitates engineered systems with demonstrated infiltration capacity, typically minimum 50mm per hour.

Acceptable systems include permeable concrete or asphalt with specified void ratios, permeable pavers with aggregate-filled joints and free-draining sub-base, and reinforced grass systems with structural cells. Standard concrete pavers on sand do not qualify unless the system includes adequate sub-base drainage and can demonstrate required infiltration rates. Developers should specify permeable paving systems during concept design and obtain manufacturer certifications confirming infiltration capacity for inclusion in planning permit applications.

The cost differential between standard concrete paving and engineered permeable systems typically ranges from $180-$280 per square metre depending on specification and site conditions. On a dual occupancy development requiring 40m² of permeable paving for driveway access, this represents $7,200-$11,200 additional cost. However, this investment can enable higher site coverage by converting otherwise impermeable hardstand to pervious surface, potentially adding bedroom or living area that generates substantially higher value than the permeable paving cost.

Stormwater Management Integration:

Amendment VC282 introduced explicit requirements that the 20% pervious area must effectively manage stormwater runoff, not simply exist as a nominal calculation. This requires demonstrating that pervious surfaces are located, designed, and constructed to intercept and infiltrate stormwater from impervious areas. A planning permit application should include a STORM or MUSIC report prepared by a qualified engineer showing that the proposed pervious areas achieve required stormwater quality and quantity outcomes.

Practical implications: pervious areas should be located to receive runoff from roofs, driveways, and paved areas rather than isolated in locations that don’t intercept stormwater. A rear yard garden bed that receives no runoff from impervious surfaces provides minimal stormwater management benefit despite satisfying the 20% calculation. Better practice involves rain gardens in front setbacks receiving roof runoff, permeable paving for driveways, and garden beds adjacent to paved courtyards with graded surfaces directing runoff to pervious areas.

Many councils now require that stormwater from impervious surfaces is directed to pervious areas for infiltration before any discharge to the drainage system. This can be achieved through graded surfaces, slotted drains directing water to garden beds, or rainwater tanks with overflow to pervious areas. The integration of stormwater management with permeability requirements represents a shift from compliance-focused design to performance-based outcomes that genuinely reduce stormwater runoff and improve water quality.

Deep Soil Zones and Tree Canopy:

Standard B2-7.2 (introduced by Amendment VC282) mandates minimum tree canopy coverage: 10% for sites up to 1,000m², 20% for sites over 1,000m². This requirement interacts with permeability provisions by necessitating deep soil zones capable of supporting canopy tree growth. Deep soil zones require minimum 1 metre soil depth, minimum 6m² area per tree, and location that enables trees to reach maturity without excessive pruning or removal.

On a 600m² site requiring 10% canopy coverage (60m² at maturity), developers must provide deep soil zones capable of supporting 2-3 canopy trees (assuming 20-30m² canopy spread per tree at maturity). These deep soil zones must be located in areas that won’t conflict with buildings, services, or future maintenance access. Front setbacks, side setbacks with minimum 3 metre width, and consolidated rear yard areas typically provide suitable locations. The interaction between tree canopy requirements, deep soil zones, and permeability calculations requires integrated site planning from the outset rather than treating each requirement independently.

Strategies for Maximising Development Potential Within Standards

Understanding site coverage and permeability standards enables developers to maximise built form whilst maintaining compliance. The following strategies, refined through SQM Architects’ delivery of 210+ projects with 98% approval rates, demonstrate practical approaches to optimising development outcomes.

Site Selection Criteria:

Evaluate sites based on the interaction between dimensions, zone requirements, and overlay controls before acquisition. A 650m² GRZ site with 30% garden area enables meaningfully more development than a 550m² site with identical requirements—the additional 100m² translates to 35m² additional building footprint after accounting for garden area and permeability. Sites with regular dimensions (closer to square than narrow rectangular) typically enable more efficient building layouts that maximise site coverage without excessive circulation space or unusable areas.

Avoid sites with restrictive overlays (particularly NCO or VPO) unless the development concept specifically addresses overlay requirements and the additional design cost can be absorbed within project feasibility. A site $100,000 cheaper but requiring $150,000 additional design and landscaping cost to satisfy overlay requirements represents poor value compared to a more expensive site without overlays.

Building Configuration Optimisation:

Two-storey construction enables maximum dwelling size within site coverage constraints. A 140m² building footprint with two storeys provides 280m² total floor area—equivalent to a 4-bedroom dwelling with generous living spaces. Single-storey construction on the same footprint limits dwelling size to 140m², typically accommodating only 3 bedrooms with modest living areas. The construction cost differential between single and two-storey (approximately $200-$300 per square metre for the upper level) is substantially less than the land cost per square metre, making two-storey construction economically efficient on constrained sites.

Minimise building footprint through efficient planning: eliminate excessive circulation space, use open-plan living areas, locate services (bathrooms, laundries) in compact zones, and consider tandem or stacked parking rather than side-by-side garages. A side-by-side double garage requires 6m x 6m (36m²) compared to tandem parking at 3m x 11m (33m²)—saving 3m² of site coverage whilst providing equivalent parking. On a constrained site, this 3m² can accommodate a larger kitchen, additional storage, or expanded living area.

Hardstand and Driveway Design:

Shared driveways reduce impermeable surface area compared to separate driveways for each dwelling. A shared driveway serving two dwellings requires 3-3.5m width compared to two separate driveways at 3m each (6m total width). On a 20m deep site, this saves 50-60m² of impermeable surface—equivalent to half the minimum permeability requirement. The saved area can be allocated to additional building footprint or maintained as garden area to satisfy minimum garden area requirements.

Permeable paving for driveways and car parking areas converts otherwise impermeable hardstand to pervious surface, enabling higher building coverage. A dual occupancy with two car spaces per dwelling (four spaces total at 15m² each = 60m²) using permeable paving contributes 60m² toward the permeability requirement. Combined with 60m² of garden beds and lawn, this achieves the 120m² minimum permeability on a 600m² site whilst providing functional car parking.

Basement and Undercroft Parking:

Basement car parking constructed wholly underground with roof less than 1 metre above natural ground level is exempt from site coverage calculations. On constrained sites where at-grade parking consumes excessive site coverage, basement parking enables additional ground-floor building area. However, basement construction costs ($800-$1,200 per square metre) substantially exceed at-grade construction, requiring careful feasibility analysis to confirm the additional building area justifies the cost.

Undercroft parking (ground floor parking with habitable accommodation above) counts toward site coverage but can be more cost-effective than basement construction whilst achieving similar site planning benefits. An undercroft garage with first-floor bedrooms above maximises building footprint efficiency on narrow sites where side-by-side parking would consume excessive width. The structural requirements for undercroft construction (reinforced concrete slab, steel or concrete columns) add approximately $150-$250 per square metre compared to standard timber floor construction, but this remains substantially less than full basement construction.

How does site coverage interact with minimum garden area requirements?

Site coverage and minimum garden area requirements operate as separate but related constraints. Site coverage limits the maximum building footprint (65% in GRZ), whilst minimum garden area specifies how much of the site must be pervious and capable of supporting vegetation (typically 25-35%). The practical constraint emerges because garden area must be pervious, meaning the 20% permeability requirement is absorbed within the garden area calculation. On a 600m² site with 30% garden area (180m²), you cannot achieve 65% site coverage (390m²) because only 20% (120m²) remains for driveways and paths after satisfying garden area and permeability requirements. The effective maximum becomes approximately 50% site coverage on sites with substantial garden area requirements.

Can I use permeable paving to satisfy the 20% permeability requirement?

Yes, but only if the permeable paving system is engineered and certified to achieve minimum infiltration rates (typically 50mm per hour). Standard concrete pavers on sand do not qualify unless the system includes adequate sub-base drainage and demonstrated infiltration capacity. Acceptable systems include permeable concrete or asphalt, permeable pavers with aggregate-filled joints and free-draining sub-base, and reinforced grass systems. You must provide manufacturer certifications and potentially a STORM or MUSIC report demonstrating that the permeable paving effectively manages stormwater runoff. The cost differential compared to standard paving ranges from $180-$280 per square metre depending on specification.

Do upper-storey balconies count toward site coverage calculations?

Upper-storey balconies with roofs above count toward site coverage regardless of whether they’re enclosed. Open balconies without roofs do not count toward site coverage. The distinction is whether the structure is “roofed”—any roof coverage triggers inclusion in site coverage calculations. A first-floor balcony with pergola roof counts, whilst an open balcony with balustrade only does not. This distinction becomes important when maximising building footprint on constrained sites—open balconies enable outdoor living space without consuming site coverage allocation.

How do councils verify permeability compliance after construction?

Councils verify permeability through Statement of Compliance inspections conducted by building surveyors. The building surveyor confirms that pervious areas shown on approved plans have been constructed as specified, including any engineered permeable paving systems. For permeable paving, this may require infiltration testing to confirm the system achieves specified performance. Developers should maintain manufacturer certifications, installation records, and any required testing results for provision to the building surveyor. Non-compliance discovered during final inspection can delay occupancy permits and require remedial works to achieve the required permeability.

What happens if my development exceeds site coverage by a small margin?

Developments that exceed site coverage standards by small margins (typically 2-5%) may still achieve planning permit approval if the application demonstrates that the site coverage objective is met through alternative design responses. The responsible authority assesses the proposal against decision guidelines including whether the increased site coverage enables better internal amenity, whether adequate pervious areas are maintained for stormwater management and vegetation, and whether the development responds appropriately to neighbourhood character. However, following Amendment VC282, applications that do not meet the site coverage standard lose deemed-to-comply status and become subject to third-party notice and appeal rights. This substantially increases assessment timeframes and approval risk, making compliance with the standard preferable in most circumstances.

Do City of Boroondara and City of Whitehorse apply different site coverage requirements?

Both councils apply the standard 65% maximum site coverage in the GRZ and 60% in the NRZ as specified in the Victorian Planning Provisions. However, City of Boroondara applies more restrictive minimum garden area requirements (often 40% in NRZ areas) compared to City of Whitehorse (typically 30% in GRZ areas). This difference in garden area requirements creates the practical distinction—Boroondara sites often achieve lower effective site coverage due to higher garden area requirements, even though the nominal site coverage standard is identical. Developers should review the specific schedule to the zone applying to their site to confirm both site coverage and garden area requirements before proceeding with concept design.

Can I include rainwater tanks in permeability calculations?

No, rainwater tanks are impermeable structures and count toward impermeable surface area. However, rainwater tanks can contribute to stormwater management objectives by capturing roof runoff and reducing discharge to the drainage system. Many councils (particularly City of Monash) mandate rainwater tanks as part of water-sensitive urban design requirements. The tanks themselves consume site area and count as impermeable, but the stormwater management benefits they provide can support applications seeking variations to permeability standards by demonstrating alternative stormwater management outcomes.

Conclusion: Strategic Site Planning for ResCode Compliance

Site coverage and permeability standards under ResCode represent fundamental constraints that determine development feasibility and project returns for Melbourne property developers. The 2025 planning reforms introduced deemed-to-comply pathways that streamline assessment for compliant applications, but the interaction between site coverage limits, permeability requirements, minimum garden areas, and tree canopy standards creates practical constraints that require careful site planning from the outset.

Successful developers understand that maximising built form within these constraints requires integrated design thinking: selecting sites based on dimensions and overlay controls, optimising building configuration for two-storey construction, minimising hardstand through shared driveways and permeable paving, and locating pervious areas to achieve genuine stormwater management outcomes rather than nominal compliance. With SQM Architects’ 98% planning approval rate across 210+ projects representing $120M+ combined GDV, our experience demonstrates that early consideration of site coverage and permeability standards during site selection and concept design directly correlates with project success and approval certainty.

For property developers in Whitehorse, Boroondara, Manningham, Monash, Knox, and Maroondah, understanding council-specific variations and local requirements proves essential for accurate feasibility analysis and concept design. The investment in professional site assessment and ResCode analysis before acquisition can prevent costly redesigns, assessment delays, and potential project failure on sites that appear viable based on nominal site coverage calculations but prove unworkable when all constraints are properly considered.

Book a Strategy Call from SQM Architects to confirm your site’s development potential and ResCode compliance strategy. Call (03) 9005 6588 or visit our website to discuss your Eastern Suburbs development project with our ResCode-focused practice.


This article provides general information about Victorian planning for property developers. It does not constitute professional advice. For specific guidance on your project, contact SQM Architects (ARBV Reg. No. 51498) for a complimentary site assessment.

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