WARRANTIES & DURABILITY

Warranties

Product warranties are typically offered by the material manufacturer/supplier. These types of warranties are based on either representation made by, or a contract with, the person or company providing the product or service.  The party providing the warranty usually decides the warranty period as well as the terms and conditions for the warranty. This is generally negotiable prior to the award of the contract.

One method of determining warranty periods is in relation to building elements with a durability requirement, taken as a percentage of the durability provision where one exists. Otherwise, warranties may be set by the market (the competition).

The existence of a product warranty does not mean the product will necessarily be durable or last for a certain number of years. Rather, a warranty only helps to repair or replace the product if there are problems, or to compensate for any damage. Additionally, a warranty is worthless if the company offering it goes into liquidation. A joint and several warranty can add a further level of protection to the principal, whereby the manufacturer (often an international corporate) also warranties their product and steps-in should the local company fail.

It is essential to be reasonable when agreeing a warranty with a material manufacturer/ supplier or other business providing the product. Any unreasonable warranty period or conditions may be priced high or not supported if something goes wrong.

There are two main types of warranty when specifying products and systems on a building project:

1. Material manufacturer/supplier warranty - generally covers the materials themselves including failures or defects due to premature aging or manufacturing defects.

2. Installer/applicator warranty - generally covers the work performed by the installer/applicator, including any installation errors.

There are other types of warranties detailed in the Masterspec specification section 1237 Warranties including:

Weathertightness and watertightness warranty- a warranty required from the contractor for a minimum period of 2 years, covering the weathertightness of the complete building envelope and the watertightness of all liquid supply and disposal systems and fittings.

When reviewing warranties consider:

• What type of warranty am I receiving?
• What is the term or time frame of the warranty?
• What type of circumstances could possibly void the warranty?
• What conditions are imposed on the building owner/ occupier so as not to void the warranty?
• Are these conditions reasonable? For example, the regularity of cleaning required.
• What does a warranty cover/ not cover?

• Does the warranty cover consequential damage? E.G., damage to other building elements relating to failure in the exterior envelope.

Durability

The New Zealand Building Code sets out the objective, the functional requirements and details performance items in relation to the durability for building work, in Clause B2 Durability. The aim is to ensure that building materials, components and construction methods shall be sufficiently durable to ensure that the building, without reconstruction or major renovation, satisfies the other functional requirements of the building code throughout the life of the building.

To comply with the Building Code, building elements must, with only normal maintenance, continue to satisfy the performance requirements of the code for the lesser of the specified intended life of the building, if stated or:

(a) The life of the building, being not less than 50 years, if:

1. Those building elements (including floors, walls, and fixings) provide structural stability to the building, or
2. Those building elements are difficult to access or replace, or
3. Failure of those building elements to comply with the building code would go undetected during both normal use and maintenance of the building.

(b) 15 years if:

1. Those building elements (including the building envelope, exposed plumbing in the subfloor space, and in-built chimneys and flues) are moderately difficult to access or replace, or
2. Failure of those building elements to comply with the building code would go undetected during normal use of the building but would be easily detected during normal maintenance.

(c) 5 years if:

1. The building elements (including services, linings, renewable protective coatings, and fixtures) are easy to access and replace, and
2. Failure of those building elements to comply with the building code would be easily detected during normal use of the building.

Also, individual building elements which are components of a building system and are difficult to access or replace must either:

• All have the same durability, or
• Be installed in a manner that permits the replacement of building elements of lesser durability without removing building elements that have greater durability and are not specifically designed for removal and replacement.

When assessing the durability of building products, regard should be given to:

• Appraisals, Codemark etc
• In service history
• Product testing
• Manufacturers' technical literature
• Site specific and environmental conditions
• Type of occupancy, anticipated use etc

Determining Warranty Periods

As previously noted, there are two main types of warranties when specifying products and systems on a building project – material manufacturer/ supplier warranty and installer/ applicator warranty.

One method of determining warranty periods is in relation to the durability requirement, taken as a percentage of the durability period where one exists.

The general rule of thumb:

• material manufacturer/supplier warranty in the range of 1/4 to 1/3 of the durability period rounded to a whole number.
• installer/applicator warranty as 1/3 of the material manufacturer/supplier warranty term, again rounded to a whole number.

1. The life of the building, being not less than 50 years Durability, for building elements:

   (i)     Material manufacturer/ supplier warranty – in the range between 12.5 years and 16.7 years.

   Suggest 17 years Material Manufacturer/ Supply Warranty.

   (ii)    Installer/ applicator warranty – in the range between 4.2 years and 5.6 years.

   Suggest 6 years Installer/ Applicator Warranty.

2. 15 years Durability, for building elements:

   (i)     Material manufacturer/ supplier warranty – in the range between 3.8 years and 5 years. Suggest 5 years Material Warranty.

   (ii)    Installer/ applicator warranty – in the range between 1.3 years and 1.7 years. Suggest 2 years Workmanship Warranty.

3. 5 years Durability, for building elements:

(i)   Material manufacturer/ supplier warranty – in the range between 1.3 years and 1.7 years. Suggest 2 years Material Warranty.

(ii)    Installer/ applicator warranty – in the range between .4 years and .6 years. Suggest 6 months Workmanship Warranty.

Commence warranties from the date of practical completion of the contract works, unless stated otherwise.

Warranties and Masterspec

When creating new branded specification work sections, Masterspec determine the warranty periods, generally based on the above criteria and confirm with the product partner prior to publication. Architects and Designers are encouraged to review the template specification section and ensure that the section once complete accurately reflects the project specific requirements. Where we identify that a section is highly technical or complex (including where supplier undertakes design work, PS1 etc.)  and the product partner is best placed to complete the section for the specifier, we add a guidance note commentary to encourage this.

For more information about Durability and links to NZBC clause B2 Durability, please refer to Ministry of Business, Innovation & Employment:

https://www.building.govt.nz/building-code-compliance/b-stability/b2-durability/