Create a renovation scope ledger

Define scope before applying any rate

Renovation rates become unreliable when the measured area and inclusions are unclear. The general room field is intended for work such as wall repairs, painting, doors, trim and ordinary room upgrades that are genuinely described by an area rate. It should exclude kitchen cabinetry, benchtops, bathrooms, flooring, demolition, services and structural work when those are entered elsewhere.

Measure only the area receiving that general scope. If one bedroom is repainted while another is stripped, insulated, rewired and relined, they should not share a single rate. Run separate scenarios or build a more detailed quantity schedule. The output labelled total per general area is a scale check, not a transferable whole-home market rate.

YourHome recommends considering renovation needs, sustainability opportunities and the existing home together. A small repair can be a chance to improve draught sealing, insulation continuity, shading, ventilation or water efficiency, but each change should be documented so it reaches the quote and contract.

Price a kitchen by components and service changes

Cabinetry cost is calculated from entered linear metres. This is a convenient early measure, but tall units, islands, corners, drawers, hardware, internal fittings, finishes and installation complexity can make equal lengths cost differently. Replace the lineal estimate with a cabinet-by-cabinet quotation once the layout is stable.

Benchtop area is separate because material, thickness, edge profile, cut-outs, waterfall ends, supports, transport and installation influence price. Measure horizontal surface area consistently and ask whether quoted rates include sink and cooktop cut-outs. Avoid treating a showroom slab price as an installed rate.

Appliances and fixtures have their own allowance. Include delivery, removal of old appliances and any specialist installation that is not already in the services line. Confirm electrical load, circuit, ventilation, gas and plumbing requirements before committing to equipment. Moving a sink or cooktop can shift cost into floors, walls, roof space and switchboard upgrades.

The kitchen direct subtotal includes only cabinetry, benchtops and the entered appliance/fixture allowance. Services, demolition, floors, design and contingency remain visible at project level rather than being arbitrarily assigned to the kitchen. For a kitchen-only project, use zero for unrelated fields and enter its relevant shared works.

Bathrooms and laundries need documented wet-area scope

The per-room wet-area input is an early allowance. Actual cost depends on room size, substrate condition, layout changes, drainage, fixtures, tiling, ventilation, waterproofing, access and the condition of concealed services. A bathroom and a laundry rarely have identical scope; calculate them separately if their allowances differ materially.

NCC housing provisions address waterproofing in bathrooms, showers, laundries and sanitary compartments. The ABCB guidance explains compliance pathways and notes that kitchens are excluded from that wet-area definition, although other requirements and good detailing still matter around kitchen fixtures and penetrations. Use the current adopted NCC edition, state or territory variations and project certification advice.

Ask quotations to identify substrate preparation, falls, floor wastes, membrane system, bond breakers, penetrations, curing, testing or inspection, tile system and warranty. Photograph compliant concealed work before it is covered. Do not use the calculator’s room allowance as a waterproofing specification.

Investigate the existing home before demolition

Existing conditions are a major renovation risk. Inspect structure, moisture, drainage, termites, wiring, plumbing, gas, insulation, ventilation and previous alterations. Homes built or renovated before 1990 may contain asbestos. The Asbestos and Silica Safety and Eradication Agency advises householders to consider this before disturbing materials.

A hazardous-material assessment should inform demolition method, access, containment, clearance and disposal pricing. Do not drill, sand or break suspect material to identify it. Other hazards can include lead paint, silica dust, mould and contaminated soil. Apply the relevant work health and safety and environmental rules.

Demolition is not simply removing visible finishes. It can include isolation of services, temporary protection, propping, salvage, loading, transport, lawful disposal, cleaning and making the structure weather-safe. Record whether the quote includes each item. Keep investigation costs outside contingency where they are already known.

Coordinate design, approvals and temporary living

The consultant percentage is applied to the direct construction scope: general rooms, kitchen, wet areas, flooring, demolition, services and structure. Surveys, approvals and certification are entered separately. Depending on work, the team may include a building designer or architect, structural engineer, energy assessor, building surveyor or certifier, interior designer, quantity surveyor and specialist trades.

Approval can depend on structural change, external appearance, heritage, fire safety, plumbing, drainage, energy performance and local planning. “Internal renovation” is not enough information to determine an approval pathway. Check with the relevant local and state or territory authorities before fixing the programme.

Renovation can make part of a home unusable. Budget a temporary kitchen, storage, pet care, security, extra cleaning and accommodation if required. Confirm whether water, power, bathroom access and cooking will be available at each stage. A longer staged project may cost more in mobilisation but reduce relocation expense; compare both cash flow and household disruption.

Issue the same documents to every bidder

Compare written quotes on the same revision. Identify prime cost items and provisional sums, the margin applied to variations, start and completion assumptions, payment stages, licensing, insurance, approvals, defects and warranty responsibilities. A cheaper quote with large unresolved allowances may transfer more risk to the owner.

The ACCC explains consumer guarantees and contract principles, while home-building contract requirements vary by state or territory and project value. Read the whole contract and use independent legal or technical advice appropriate to the commitment. Do not rely on an estimate page as contract advice.

Use contingency and GST consistently

The calculator adds all direct construction lines, then calculates professional fees as the entered percentage. Approval and temporary-living amounts are added to form the pre-contingency subtotal. Contingency applies to that amount. GST is added last only when the selector says the inputs exclude it.

Convert every quote to the same GST basis before entry. A supplier price may include GST while a trade estimate or consultant proposal states it separately. Mixed inputs create a plausible-looking but incorrect total. Keep a source, date, revision and inclusion note for every number.

Contingency should reflect design maturity and existing-condition risk. It is not a budget for optional upgrades. Maintain separate change control: description, reason, quoted price, time impact, approvals and remaining reserve. A late kitchen selection can affect cabinetry, electrical, plumbing, ventilation and benchtop details together.

Finance and property value are excluded. If borrowing, model interest, valuation, fees, staged drawdowns and the cost of delay separately. A renovation may improve comfort, resilience and operating cost without adding its full price to resale value.