Painting is a crucial part of maintaining a building’s overall health and appearance. Whether you are planning to move to a new building or want to have paintwork on your existing building, it is important to make sure that the paint finishing complies with the set standards. In New Zealand, builders and painters need to follow the AS/NZS 2311:2017 guide while painting buildings. Let’s try to understand the paint finishing standards followed by the industry.
Highlights of the Paint Finishing Standard
Standard of Painting
While working on painting projects for buildings in New Zealand, it is mandatory to use coatings suitable for the relevant conditions and wear and tear. Unless documented otherwise, the painting work is considered defective if it does not comply with the manufacturer’s installation instructions. The same applies to painting work that does not comply with AS/NZS 2311:2017, the guide to the painting of buildings.
Requirements for Surface Finish of Paintwork
According to the paint finishing standards, the paintwork is considered defective if there are application defects or blemishes. These blemishes can be any of the following:
- Paint sags
- Paint runs
- Dust
- Bare or starved painted areas
- Wrinkling
- Colour variations
- Surface cracks
- Irregular and coarse brush marks
- Uniformity of gloss level
- Sanding marks
Any irregularities in the surface visible from a normal viewing position are enough to declare a surface finish defective. Excessive overpainting of fittings, skirting, trims, glazing, architraves, and other finished edges is also considered a defect.
Requirements for Nail and Screw Fixings
When it comes to painting over nail and screw fixings, painters also need to comply with a standard for paint finishing. Fixings of unfilled depressions caused by fixings are considered defects in painted or stained surfaces if they are visible from a normal viewing position.
Mechanical Damage and Natural Defects on Surfaces
Painting professionals need to ensure that painted or stained surfaces are free of defects. If holes and any other unfilled depressions are visible on painted or stained timber surfaces, they are considered defects. These defects may result from mechanical damage, surface splits, or natural characteristics such as gum pockets.
Paint Durability Requirements
Unless documented otherwise, paint coatings are considered defective if they start to lift, flake, blister, or fade within a predetermined minimum period. The minimum durability of coated finishes is shown in the table below:
| Coating | Minimum Durability |
| Exterior Acrylic | 36 months |
| Exterior Enamel | 24 months |
| Exterior semi-transparent stains | 12 months |
| Exterior clear finishes | Not recommended |
| Interior (all finishes) | 36 months |
In New Zealand, all preparation and painting work should comply with AS/NZS 2311:2017, the guide to painting buildings.
The Importance of Complying with Paint Finishing Standards
As a way of cost-cutting, many builders of new houses do only two coats of paint on new plasterboard. The standard for painting requires a minimum of three coats on all new unsealed surfaces unless mentioned otherwise by the manufacturers. These builders often get away with it as the buyers have no clue about the fewer-than-recommended number of coats. In such cases, the paintwork will have lower durability and lead to pre-mature paint failure.
AS/NZS 2311:2017 states that the first coat must be a plasterboard sealer. This coat will seal the plasterboard joins and the plasterboard. The next coats should be top coats that offer a level of washability or scrubbability. Always see the builder’s specifications before you sign the agreements. Make sure they meet the requirements of AS/NZS 2311:2017. It is also a common practice among builders to use matte paint on walls. They usually do it to hide imperfections in the plaster. While this may look okay at a glance, matte paint does not have the washability or scrubbability of low-sheen paint.
Generally, you can notice variations in the surface colour, texture, and finish by looking at them from a normal viewing position. You need to look at a distance of 1.5 m or greater (600 mm for appliances and fixtures) with the surface or material being illuminated by “non-critical light.”
In Conclusion
The AS/NZS 2311:2017 guide to the painting of buildings exists to help professionals as well as homeowners to have a clear understanding of the quality of paintwork on their buildings. These standard guidelines help you ensure that the paintwork is free from defects and durable enough to last the minimum period mentioned in the guide.
