Exterior Painting: DIY vs Professional - NZ Homeowner Guide

Exterior coatings contribute to the cladding system's weather protection and appearance. UV, rain, salt and temperature exposure can degrade coatings; inspect failed paint and the underlying cladding rather than assuming repainting alone will resolve moisture, decay or mould.

The decision between DIY and professional painting comes down to honest assessment of your skills, available time, the complexity of your specific property, and realistic cost comparisons. Both approaches can deliver excellent results, but they suit different situations.

The True Cost of Professional Painting

There is no reliable nationwide price for an "average" exterior. Cost depends on measured area, height and access, cladding and coating condition, repairs, hazardous-material controls, coating specification, labour and location.

• Ask each provider to price the same measured scope and preparation standard
• Identify access equipment, repairs, hazardous-material controls and exclusions
• Specify coating products, coat numbers, colours and surface areas
• Record timing, cleanup, warranties and any possible variations

Do not assume a quote includes labour, paint, access equipment, repairs, preparation, cleanup or a set number of coats. Have the written quote identify every inclusion, exclusion, warranty and manufacturer requirement.

Compare written quotes on scope, preparation, products, coat numbers, access, repairs, timing and warranties, not price alone. Consumer Protection recommends checking why prices differ rather than assuming what a low or high quote includes.

DIY Costs: More Than Just Paint

For a DIY cost, measure each surface and price the specified coating quantity, primer, preparation materials, access equipment, protective equipment, testing, containment, cleanup and waste disposal.

Paint price, coverage and required coat numbers vary by product, colour and substrate. Use the current technical data and coverage rate for the specified system, allow for surface condition and application losses, and obtain current supplier pricing.

Preparation may require cleaners, compatible fillers and sealants, abrasives, masking and containment materials, primer and disposal. Determine the products and quantities only after inspecting the substrate and checking hazardous-material risks.

Access equipment and fall controls can materially change the scope. Select them from a task-specific risk assessment and obtain a current site-specific hire or contractor quote; a ladder is not automatically suitable for sustained exterior painting.

Preparation: Where Paint Jobs Succeed or Fail

Ask any professional painter what makes the difference between a paint job that lasts and one that fails, and they will tell you it is preparation. Paint applied over poorly prepared surfaces will peel, blister, and crack regardless of how expensive it was.

Preparation depends on the cladding, existing coating and new system. First check for lead, asbestos, decay, damaged cladding and weathertightness issues. Then follow the coating and cladding instructions for cleaning, dust control, repairs, sanding, filling, sealing, priming and topcoats; water-blasting and dry sanding can be unsafe or damaging in some situations.

Health New Zealand says buildings and houses painted before 1980 can have lead-based paint and that it cannot be identified by appearance alone. Test first or assume pre-1980 paint may contain lead. Professional removal is recommended where possible; any DIY removal needs the specified respirator, containment, dust-suppression, cleanup and disposal controls.

Preparation time depends on inspection findings, access, surface area, coating condition, repairs and safety controls. Scope it before comparing DIY and contractor programmes.

When DIY Makes Sense

DIY may reduce paid labour, but its suitability and total cost depend on competence, time, access, equipment, testing, safety controls, repairs and the coating specification.

A single storey does not make ladder work automatically suitable. Identify fall hazards and select access equipment that keeps people safe; sustained painting or work requiring reach, force or materials may need a work platform or scaffold.

Simple cladding with minimal details speeds up the work considerably. Flat weatherboards or sheet cladding paint quickly. Ornate villas with detailed joinery, multiple gables, and decorative elements take dramatically longer and require more skill to paint neatly.

Apparently sound paint may reduce some preparation, but first identify the existing coating and check adhesion, contamination, sealants, hidden damage and hazardous-material risks; then follow the specified preparation system.

Estimate the programme from the measured scope, preparation and repair needs, drying and recoat times, safe-access setup, weather window and available labour. Protect unfinished surfaces as the product and cladding instructions require.

When Professionals Are Worth the Money

Some situations strongly favour hiring professionals despite the higher cost.

Multi-storey work presents material fall risk. Use a task-specific working-at-height plan and suitable access equipment, and include competent erection, inspection and hire requirements when comparing DIY and contractor options.

Extensive decay, coating failure or substrate damage may need assessment and repair outside a painting scope. Confirm the cause, required trade and any consent implications before coating over it.

Lead paint can cause serious illness. Health New Zealand recommends professional removal where possible, but if DIY removal is undertaken its specified testing, respirator, wet-method, containment, cleanup and disposal precautions must be followed.

Ask contractors for a project-specific programme and build a DIY programme from the same scope, weather allowances, drying times, access setup and repair work. Do not rely on generic one-week or weekend comparisons.

Choosing Paint That Lasts

Coating durability depends on the specified system, substrate, preparation, colour, exposure, application and maintenance. Compare current technical data and warranties for the exact products rather than generic lifespan claims.

Compare products using their declared substrate compatibility, preparation and primer requirements, coverage, application conditions, durability evidence, maintenance and written warranty. Brand tier or price alone does not establish performance.

Colour can affect surface temperature and some cladding or coating warranties. Check the cladding and coating supplier's light-reflectance, colour and exposure limits before choosing a dark colour.

Select the coating system for the exact cladding, existing coating, condition and exposure. Follow the manufacturer's compatibility, primer, topcoat and application specification rather than assuming one generic paint chemistry suits most exteriors.