In the last Journal I claimed that' from the timber designers point of view timber is the "innocent" material in the current debate on weathertightness'. I have received some supporting feedback on this statement, one even classifying it as provocative! My thanks to John Little who pointed me to the new publication the "Approved Document for Building Code Clause E2 External Moisture" . This covers the way buildings should be built to provide adequate resistance to the penetration and accumulation of moisture from the outside. The changes will apply to buildings covered by the scope of NZS 3604: 1999 (Timber framed buildings); essentially it applies to timber framed buildings up to three storeys or 10 metres high.

The changes in E2/AS1 are significant and include such matters as – The introduction of a risk management approach to weathertightness management: much more detail around the design of flashings for parapets, decks, balustrades and balconies: the inclusion of more cladding types : reinforcing the details around the design of drained cavities. The BIA has also introduced a new verification method called E2/VM1 this being a testing method to allow cladding manufacturers to prove weathertightness of their products when used in certain areas. The new E2/AS1 will be effective for consents applied for from 1 February 2005. Work consented under the current E2/AS1 has until 31 January 2006 to be completed. These dates are subject to industry feed back to the BIA by 31 July 2004. The new E2/AS1 will be effective from 1 July 2004 and is being further explained at Seminars around the country by BIA and BRANZ at the present time.. Contacts are at www.bia.govt.nz or 0800 242 243.

I hope the above information assists in the design, performance and installation of claddings. The Timber Design Society will be covering some of this as part of the programme at our next Seminar in November when we will be dealing with specific case studies ,some part of which will touch on weathertightness.

There has been some encouraging progress on the funding initiatives introduced by TDS some months ago ie. the funding of a computerised timber design package and also the funding for 4 of our University Faculties to assist in additional staff and research to increase the serious shortfall in timber design teaching for buildings and furniture. However as the development of these initiatives is ongoing a report will appear in the next Journal. Suffice to say at this stage that there is written and financial support from some parts of industry (one Company has put in $100,000 for 3 years) which is encouraging progress. As the architects, engineers and other designers specify and use timber in their designs there will be more timber processed in NZ and less exported as logs. Surely an admirable objective in addition to the real value of using timber design.