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Title / Explain liquid roof membrane installation, re-roofing considerations, and potential problems
Level / 4 / Credits / 4
Purpose / People credited with this unit standard are able to explain: deterioration factors for liquid roof membrane; considerations for restoration of faulty liquid roof membrane; and detail for mounting and fastening plant to liquid roofmembrane.
Classification / Plumbing, Gasfitting and Drainlaying > Roofing
Available grade / Achieved
Explanatory notes
1Legislation relevant to this unit standard includes but is not limited to – Health and Safety in Employment Act 1992, Building Act 2004.
2The following applicable document is available for download on the Department of Building and Housing website:
Building Code compliance document Clause E2, containing Acceptable Solution E2/AS1 for External Moisture.
3The New Zealand Building Code (NZBC) is a schedule to the Building Regulations 1992. It provides requirements for compliance with the Building Act 2004 when constructing a new building or altering an existing one. The Building Code sets out performance standards that building work must meet and covers aspects such as structural stability, fire safety, access, moisture control, durability, and services and facilities.
4Definitions
Manufacturer recommendations – refer to product information and product data sheets provided by the manufacturer of any given product.
Job specifications – refer to the documented information found in construction drawings, project specification documents, legislation, regulations and codes.
5This unit standard may be assessed against off-job.
Outcomes and evidence requirements
Outcome 1
Explain deterioration factors for liquid roof membrane.
Evidence requirements
1.1UV deterioration rate is explained in terms of film thickness effects.
1.2Deterioration factors are explained in terms of foot traffic effects.
1.3Deterioration factors are explained in terms of application thickness.
Outcome 2
Explain considerations for restoration of faulty liquid roof membrane.
Rangefaults may include – poor installation or deterioration;
restoration includes – localised repair, total replacement.
Evidence requirements
2.1Roof inspection activities are explained in terms of determining existing condition and potential hazards prior to repair or replacement.
2.2Importance of work planning sequence is explained in terms of minimising impact to occupants and potential risks of exposure damage to building.
2.3Considerations for determining the extent of membrane repairs or replacement are explained in accordance with job specifications.
2.4Considerations for re-roofing and repair are described in accordance with NZBC requirements.
Rangeincludes but is not limited to – territorial authority requirements.
2.5Solutions for membrane repairs or replacement are proposed in accordance with manufacturer recommendations and the NZBC.
Outcome 3
Explain detail for mounting and fastening plant to liquid roof membrane.
Evidence requirements
3.1Detail of mounting structure, membrane coverage, and fastening placement are explained in accordance with manufacturer recommendations.
Replacement information / This unit standard and unit standards 25291 and 25297 were replaced by unit standard 30018.This unit standard is expiring. Assessment against the standard must take place by the last date for assessment set out below.
Status information and last date for assessment for superseded versions
Process / Version / Date / Last Date for AssessmentRegistration / 1 / 23 January 2009 / 31 December 2020
Review / 2 / 16 March 2017 / 31 December 2020
Consent and Moderation Requirements (CMR) reference / 0227
This CMR can be accessed at
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and which are assessing against unit standards must engage with the moderation system that applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies to this standard are outlined in the Consent and Moderation Requirements (CMR). The CMR also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.
The Skills OrganisationSSB Code 100401 / New Zealand Qualifications Authority 2018 / / New Zealand Qualifications Aut