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Building a weathertight home

Guidance published in accordance with section 175 of the Building Act 2004.

They are not Acceptable Solutions and Verification Methods, but are intended to provide general guidance to designers, building consent authorities (BCAs), builders, etc.

Dealing with timber in leaky buildings

Dealing with timber in leaky buildings guide cover. What sort of publication it is: Colour A5 booklet
Who it's for: Builders and BCAs and leaky home assessors. Homeowners may also find the information useful.
What it contains: Practical advice on dealing with decayed timber once the cladding is removed. Topics covered include:
  • Repairing a leaky building
  • Types of decay
  • Removing decayed timber
  • Health and safety issues
  • Site applied preservative treatment
  • Other sources of information

How to get it: Download a PDF or call 0800 242 243 for a hard copy

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Weathertightness: Guide to remediation design

Guide to Remediation Design publication cover What sort of publication it is: Colour booklet
Who it's for: Designers who are either already undertaking remediation design work or, are considering taking it up. BCAs, builders and homeowners may also find the information useful.
What it contains: It outlines understanding the owner’s position, understanding the building, understanding options available, design considerations, construction considerations and detailing remediation solutions.

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Weathertightness: Guide to the diagnosis of leaky buildings

What sort of publication it is: Colour booklet
Who it's for: Assessors and building surveyors who are undertaking comprehensive building assessments of leaky buildings.
What it contains: : It outlines the processes and techniques used by an assessor including; pre-site work, site visits, non-invasive investigation, invasive investigation, destructive investigation, analysing the evidence, developing a recommendation and reporting. It also covers investigative tools available to the assessor.

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External moisture – A guide to weathertightness remediation

External moisture – A guide to weathertightness remediation cover What sort of publication it is: Colour booklet
Who it's for: Designers, building specialists, remediation contractors, building officials, and others. It is especially relevant to consultants advising clients and owners on repair of leaky buildings.
What it contains: It outlines a process that consultants should follow when advising owners on weathertightness repair of buildings from initial identification of the problem, through organising of repair contracts to ongoing maintenance recommendations. It also highlights where specialists can assist in the remediation process, such as investigating specific causes, deciding repair strategies and analysing decayed timber.

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Constructing cavities for wall claddings

Constructing cavities for wall claddings cover. What sort of publication it is: Colour booklet
Who it's for: Builders
What it contains: Guide to drained and vented cavity construction for timber-framed buildings, as described in the Acceptable Solution for Building Code Clause E2 External Moisture (E2/AS1).

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External moisture – a guide to using the risk matrix

A companion guide to the Acceptable Solution E2/AS1

External moisture – a guide to using the risk matrix cover What sort of publication it is: Colour brochure
Who it's for: Designers, builders and building officials
What it contains: Guidance for using the risk matrix from E2/AS1 to assess a building design for weathertightness. The main topics it covers are:
  • Weathertightness: The E2/AS1 approach
  • The risk assessment process
  • Key risk factors
  • Applying the risk factors - worked examples

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External moisture - An introduction to weathertightness design principles

External moisture - An introduction to weathertightness design principles cover What sort of publication it is: Colour booklet
Who it's for: Builders and building officials
What it contains: The principles of weathertightness design that have helped shape the Acceptable Solution E2/AS1 are explained in this guidance document. The document provides a valuable summary of critical performance components for effective cladding systems. It sets out principles that act as a checklist for performance-based designs outside the Compliance Documents. Knowledge of the principles of weathertightness is considered essential for all designers and builders of small- to medium-sized buildings, for building officials, educators and those with a general interest in weathertightness such as insurers, developers and funders of building projects.  

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Archived weathertightness-related publications

New weathertightness solutions - published by the Building Industry Authority in October 2004 for builders and people building or renovating a home.

Critical requirements for the assessment of 'monolithic' claddings - published by the Building Industry Authority in April 2004 for building officials.

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