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Working at Alert Level 2

Technical issues

BRANZ testing services


Have a question?

If you have a question or comment on the COVID-19 situation or its impact on your work, please phone or email the BRANZ technical helpline:
For the building industry: 0800 80 80 85 press 1
For the public: 0900 5 90 90 (calls cost $1.99/min + GST)


Working at Alert Level 2 

What are the main differences between Alert Levels 2 and 3 for residential construction sites?
New guidance from the government for work required under Alert Level 2 has required changes to the Residential Construction Protocols:

  • Recommend workers stay 2 m from those outside their work bubble.
  • Workers stay 1 m minimum from all other workers unless necessary and a risk assessment has been completed
  • Non-essential visitors can undertake site visits with prior notice.
  • Multiple trades can work onsite.
  • Workers can leave site for food/drink. However, they must complete the sign out and sign in processes.
  • Maintain minimum 1 m physical distancing from delivery team and 2 m where possible.

See the full Residential Construction Protocols here: 

What are the main differences between Alert Levels 2 and 3 for vertical and horizontal construction sites?
New guidance from government for working under Alert Level 2 has required amendments to the V&H Construction Protocols.

  • People working together should keep 1 m physical distancing unless other mitigating measures are in place.
  • When in public, people should keep 2 m physical distancing from people they do not know.

See the full V&H Construction Protocols here:

Can we work in client homes where clients are living? 
The requirements are outlined in the protocols at
Completing renovation work on homes where clients are living presents additional challenges, and careful consideration should be given to when such work restarts based on the specific nature of the work.

  • All COVID-19 controls in the protocols should still apply and the client family members treated like a contracting company/visitor.
  • Additional consideration would need to be given to toilets and kitchens, which should not be shared between client family members and contractors.
  • Take all practicable steps to separate the worksite from the occupied area of the home.
  • Consider an appropriate daily cleaning regime for the nature of the site and areas being occupied.

Can we open our display homes to the public? 
The requirements are outlined in the Display Home/Selection Centre Limited Operation protocols at

  • Each display/show home or selection centre site operating at Alert Level 3 or 2 needs to have in place a COVID-19 Safe Operating Plan. This plan will guide how the principal or key sales personnel will manage appointments and the controls they will use to minimise the risk of COVID-19 transmission.
  • It is the responsibility of the site owner (the party responsible for overall site coordination) to ensure this plan is in place. The site owner may be a group home builder, a project manager or a small builder/contractor. 
  • There must always be a nominated person of responsibility on site while any consultation/visit takes place.
  • These protocols are separated into four sections: before arriving on site, site entry, site operations (including deliveries and unscheduled visitors) and leaving site.

Technical issues

There is mould on treated timber stored under plastic for 5 weeks - can we still use it?
Generally, most of the treatments on the market are specifically for the minimisation of rot and aren't as effective at stopping mould growth. Some timber does have added mould treatments, but they aren't a requirement for timber preservation. 

If there is mould on the timber, there are three things to consider - structural capacity and stiffness, hazardous mould and aesthetics.

Structural capacity and stiffness: The mould itself is unlikely to affect structural capacity/stiffness, but the timber needs to be dried to an acceptable moisture level. The surrounding trapped moisture/humidity inside the plastic wrapping has caused the issue. If it can be removed to allow some airflow, that will help dry it out.

NZS 3602:2003 Timber and wood-based products for use in building includes recommendations on moisture content levels for timber products. It includes a series of tables for various building areas and systems and moisture content ranges that need to be considered for different Building Code-required life spans. A free version of this standard can be found here:

Plasterboard and plywood manufacturers have requirements for the moisture content level of timber framing that should be achieved before the product can be installed. Check their technical literature.

Hazardous mould: If there is any concern that the species of mould could be hazardous, it will need to be identified. There is an easy process for taking samples on site (using tape and baking paper) and sending them directly to a lab such as Biodet Services for specific identification.

Aesthetics: Mould can lead to unsightly staining. Is the mould likely to affect any aesthetic requirements if the timber will be visible on completion of the building? If this is an issue, the mould and staining will need to be removed.

Some industry providers have information on the effects of mould and how to remove mould safely - for example, Moulds on timber (CHH Woodproducts Technical Note September 2018).

If steel reinforcing bars have become rusty during the lockdown, who decides how rusty is too rusty? 
Exposed steel reinforcing bars may exhibit a light rust caused by prolonged exposure to moisture and air, but this is normal and not a cause for concern. However, if the steel is showing signs of chloride-induced corrosion such as pitting and extensive scaling to reinforcing bars, it should not be used unless the material has been checked for strength and cross-sectional area limitations. If the strength and cross-sectional area can meet specific requirements, remove the extensive corrosion products (particularly loose products) on the reinforcing bar surface before use. However, it would be better not to use reinforcing bars already showing extensive surface corrosion and to replace with new reinforcing bars.

The following people/organisations will be able to help:

If an underlay has been exposed to the weather during the lockdown, how do we know it is still fit for purpose?
It is critical that an underlay has retained its tensile strength and resistance to water penetration after UV exposure.

Wall underlays have a typical UV exposure limit of 30-60 days maximum. Roof underlays tend to have a 7-day limit as they are typically covered straight away. There are extremes: some manufacturers say their products can last up to 180 days. For information on your product's exposure limits, check the manufacturer's installation/application instructions (and BRANZ Appraisal, where available).

NZS 2295:2006 Pliable, permeable building underlays requires roof and wall underlays to retain at least 85% of their mechanical strength after UV exposure. It sets out requirements for UV exposure testing. A free version of this standard can be found here:

In addition, BRANZ considers that the product should also maintain resistance to water penetration (head of water) after UV exposure - i.e. 20 mm for wall underlays and 100 mm for roof underlays.
Contact the manufacturer for more information and possible solutions.


BRANZ testing services

Are the BRANZ testing services operating at Alert Levels 2 and 3?
BRANZ has resumed the majority of its commercial testing work. Contact BRANZ for more detail:
(04) 237 1170

For Appraisals only:
Freephone: 0800 080 063 (for Appraisal enquiries only)



What do we do if there is no contract with the residential client or the contract wasn't signed?
Under the Building Act 2004, it is mandatory for the main contractor to have a contract with a homeowner for residential building work over $30,000 (including GST). You can be fined if you don't have a contract in place.
If your building work is above $30,000 (including GST) and you do not have a contract, you should try to negotiate a contract with your client as soon as possible.

However, if there are any areas of dispute or there are delays or variations due to the lockdown, you may need to seek professional advice from a suitably qualified person.
See MBIE's guidance here: 

What is the government doing about contracts with government agencies? 
Government has worked with the Construction Sector Accord to release new guidance to the sector on procurement and to variations to contracts due the COVID-19 lockdown.

Guidance to government agencies on a consistent approach to construction contracts during the COVID-19 disruption. Private sector clients are encouraged to also follow the guidelines.

Contractual guidelines for procuring agencies

Guidance to government agencies on determining the fair value of variations due to COVID-19 disruption.

Contract variation guidelines

Guidance to government agencies on discussions with contractors re essential services, procurement, contracts, and business continuity plans.

General COVID-19 procurement guidance