Christchurch – Building the Future

CONSTRUCTION

Christchurch – Building the Future

Richard Maiden and Rebecca Ward review the impact of the Canterbury Earthquake Recovery Act 2011 and the Canterbury Earthquake (Building Act) Order 2010 on the repair of earthquake-damaged buildings.

The recent earthquakes in the Christchurch area have caused massive damage to its buildings and infrastructure requiring the region to embark on a major programme of reconstruction.

To ease the ‘red tape’ surrounding the legislative requirements for building work, the government passed the Canterbury Earthquake Response and Recovery Act 2010 (now repealed and replaced by the Canterbury Earthquake Recovery Act 2011 (CER Act)) and the Canterbury Earthquake (Building Act) Order 2010 (CE(BA) Order). While heralding immediate and obvious benefits, these pieces of legislation raise a number of concerns because the far-reaching consequences of the changes they endorse may not, in their entirety, be realised for some time to come.

Building Consents

An issue at the forefront of this legislation is the immediate need to make dangerous or unsanitary buildings safe. The CE(BA) Order (as amended on 13 December 2010) empowers Christchurch City Council, Selwyn District Council, and Waimakariri District Council to (amongst other things) demolish buildings owned by others and may require owners of damaged building to demolish them, based on inspection and categorisation as to the degree of damage.

Under section 38 of CER Act, the Chief Executive of the Canterbury Earthquake Recovery Authority (CERA) is also given extensive powers and may “carry out or commission [building] works” as he sees fit. Building Works include demolition as well as erection, reconstruction, removal, and disposal of any building. Under normal circumstances, a building consent would be required for such works, and at section 38(6) of the CER Act, the requirement to obtain resource and/or building consent is reinforced but qualified by stating that this requirement can be varied by an Order in Council made under that Act. In addition, section 6 of the CE(BA) Order extends the provisions of section 41 of the Building Act 2004, adding at section 41(1)(e) the circumstances in which a building consent is not now required and includes the exemptions, modifications, and extensions pursuant to the Order.

On a practical level, this means that where a building consent would usually be required for the demolition of a building, in the Canterbury regions, now it is not.

As yet, there appears to be no revision to the present and existing requirements to obtain a building consent for general building work as opposed to demolition work, and the only exceptions are provided in Schedule 1 of the Building Act. Paragraph 1(a) of that Schedule allows any “lawful repair and maintenance using comparable materials, or replacement with a comparable component or assembly in the same position, of any component or assembly incorporated or associated with a building” to proceed without a building consent. However, paragraph 1(a)(ii) excludes any “component or assembly contributing to the building’s structural behaviour or fired safety properties” and similarly in paragraph 1(a)(iii) any “repair or replacement (other than maintenance) of any component or assembly that has failure to satisfy the provisions of the building code for durability, for example, through a failure to comply with the external moisture requirements of the building code” is excluded and still requires a building consent.

Complying With the Building Code

We do not believe that earthquake damage can be construed as a building durability failure, but the compromising of the structural behaviour or fire safety of a building by an earthquake would generate the requirement to obtain a building consent. Consequently, once the initial period of demolition has passed, we foresee overworked Council officers desperately trying to process a huge volume of applications for the rebuilding and repair of earthquake-damaged buildings.

It is important to remember that while the resource and building consent requirements may have been relaxed, it is still a requirement that any building works must comply with the Building Code. The Building Code applies equally to demolition and new construction, including the rebuilding of demolished buildings and the repair of existing buildings, and it is in this area that extreme care should be taken by all parties in the building process, including owners, professional advisers, builders, and what are known as subcontract trades such as plasterers, plumbers, roofers and the like.

And so we are left with a looming problem for the future. In an attempt to promote the rebuilding of Christchurch as quickly as possible, there is a risk of constructing buildings, refurbished or new, that do not comply with the Building Code. And in light of the fact that the Building Code is performance-based, many buildings may in the short-term be seen to perform, but in the long-term are likely to fail. For those of you in the ‘leaky building’ arena, this statement will have some resonance. It is so often the case that damage to buildings goes unnoticed by a lay owner for many years, or is alternatively concealed within the structure of the building, and by the time it is found, it is too late to carry out economic repairs. Carrying out building work or repairs to existing buildings that is compliant with the Building Code is a complex process and requires a high degree of technical knowledge, and in the haste to rebuild Christchurch, there is the very real risk these standards will slip.

Ensuring Long-Term Durability

Required remedial works will obviously vary depending on building type and age, and there will be a wide range of damage suffered as a result of the earthquakes impacting on weathertightness and long-term durability. Despite any relaxation of the requirement for a building consent, compliance with the Building Code is still required, and in the rebuild and repair of existing buildings, particular attention should be paid to the impact of code clauses E2 (External Moisture) and B2 (Durability). With this in mind, potential future and subsequent building owners will need to exercise extreme caution when purchasing buildings in the Christchurch area.

There are many examples of commonly experienced earthquake damage, from flashings above windows and doors becoming dislodged allowing water entry, to the movement of foundations. While the movement of roof flashings (causing water entry) may seem a relatively minor defect, this would in all probability go unnoticed for months ,if not years, depending on the amount of water entry, but, nevertheless, it would be sufficient to promote fungal growth in any timber present.

Cracks in cladding (on timber-framed buildings) or in the surfaces of masonry buildings will cause water entry. It is not enough to simply repair a crack, as water which has entered the wall will have little ability to dry out, thus causing fungal decay behind a repaired wall and a festering problem for future discovery.

Foundation movement has significant issues for long-term durability – not only with structural integrity but with the adequacy of damp-proof membranes. If a damp-proof membrane beneath a concrete floor slab has been ruptured by seismic movement, then the ability of the floor to comply with the Building Code is compromised, and the floor is likely to develop damp patches, causing damage to anything in contact with it, such as floor coverings, skirting boards, and the like.

The waterproofing of basements raise similar problems to foundation movement, and the rectification of both can usually only be achieved by removal or chemical injection and/or a chemical coating.

Some buildings may be constructed on reinforced concrete or timber piles which are joined to a concrete floor slab, and seismic movement may compromise both the piles and the junctions to floor slabs. An area of expertise better left to structural and geotechnical engineers, but of concern to any building surveyor.

There will also be instances where the level of the ground has risen, and we see potential claims surrounding the issue of the levels between the internal floor slabs and the exterior ground surface causing a weathertightness problem, ie the wall cladding becoming too close to the ground.

There are obvious issues where drainage pipes and other underground services have failed, and structural movement will have caused obvious stresses and failure of building elements including roof trusses, seismic restraints, and fire protection.

Earthquake Failure Vs. Poor Building Practice

The difficulty for the future in building failure investigation will be discerning between failure due to the earthquake and failure due to poor building practice, including poor building practice during the rebuild. A crack in a building’s cladding can usually be identified as to its cause and time of occurrence, but, of course, there will be claims that the earthquake caused the damage to the cladding of a building (we have a client currently in Auckland who believes this to be the case!).

Should the Chief Executive see fit to relax the provisions of the Building Code for Christchurch in order to speed up the rebuilding process, then we see an ample supply of work for building surveyors, lawyers, and dispute resolution professionals in future years.

Richard Maiden is a director and Rebecca Ward is legal support with Prendos. Richard can be contacted on 09 486 9420 or [email protected], and Rebecca can be contacted on 09 970 2619 or [email protected].

NZLawyer magazine, issue 160, 20 May 2011

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