This page seeks to provide a brief guide for members of the public, customer and contractor alike, on the basics of what is good concreting practice in a domestic environment. This information is for general guidance only, it is not intended to be definitive.
NZ Concrete Contractors Members are responsible for producing quality work, adherence to regulations and a professional approach. Wherever possible choose a NZ Concrete Contractor Member for your job. See our Find Members tab for a list of NZ Concrete Contractors in your area.
For additional information follow the links at the bottom of the page to Concrete New Zealand (CNZ) and NZ Ready Mixed Concrete Association (NZRMCA) resources.
When You Need Concrete Laid
- Do your research into concrete placers located in your area; are they a member of the NZCCA?
- Check with your local ready mix suppliers to help gauge local concrete placer’s reputations for quality and consistency
- Obtain quotes from reputable concrete placers who are competent in the work you require.
- Ask to see examples of their work and ascertain guarantees for your requirements.
- Are they willing to discuss your job with you i.e. expectations, timelines, any site difficulties?
Information on Quotations
- Should clearly show this information (where appropriate and applicable for the nature of the work):
|Concrete Strength:||(Advised Min. is 20MPA for Driveways & Floors)|
|Concrete Depth:||(Min. for Driveway 100mm)|
|(Min. for Residential Floor 100mm)
(Min. for Car Port Pad 100mm)
(Min. for Pathway 75mm)
|Decorative System:||(e.g. Stamped, Coloured, Exposed Aggregate, etc)|
|Colour:||(e.g. Charcoal, Terracotta, Black etc)|
|Pattern:||(e.g. Slate, Tile, Random Stone etc)|
|Area:||(Square Metreage measurement of total concreting area )|
|Texture:||(e.g. Exterior – Broomed, Hand-troweled, Texture Roller etc )|
|(e.g. Interior – Polished, Decorative Cut etc)|
|Sealant:||Is the concrete to be sealed or not? How many coats?|
|(N.B. Sealant should not be applied within seven days)|
|Drainage:||Are there drainage needs? Are sumps, drains etc required?|
|Cost:||Is it quite clear? Are the services to be provided covered?|
|Is the GST Inclusion or Exclusion in the price clear?|
|Terms of Payment:||Ensure this is clear on your quote|
- Ensure you are clear with your Concrete Contractor if payments are required in stages of progress.
What You Need to Know About Placing & Finishing Concrete
- Not all concrete placers are NZ Concrete Contractors Association members, nor are they required to have any industry or government registration or formal training recognition
- All concrete can crack but a NZ Concrete Contractor Member should adhere to these guidelines to minimise the possibility:
- The foundation ground should have fill and be compacted
- Concrete depth should be even over the entire job
- Whilst steel mesh reinforcing is not compulsory for driveways, its tensile strength helps prevent cracking and is generally recommended
- Control cuts, to the relevant NZ Standards, should be made in critical and stressed areas on the day of the pour or within 24 hours under normal circumstances, dependent on the season and drying conditions
- Curing is required for floors; ascertain how this will be achieved
- A newly poured driveway should not be used for seven days, with 28 days being the industry standard for maximum strength achievement
- Plain or coloured concrete will have colour variations due to chemical reactions during the time of the drying processes
- Exposed aggregate concrete will always have a small quantity of aggregate and sand loss over normal wear. This can be considerably minimised by sealing
- Concrete is the only construction material that is delivered to a construction site in its raw form, a liquid state which is influenced by the weather (wind conditions and temperature), the mix design as well as placing and finishing
Follow these links to technical information