Auckland builder George Levick expects tougher new seismic standards to be a big boost to the construction sector.
Levick, of Priority One Construction, specialises in villa and bungalow renovations and a large job restoring a Devonport villa is finishing after his team built a new basement so substantial he said it was not unlike a swimming pool.
Structural elements of villas and bungalows, chimneys and brick facades could all need strengthening under the new rules, he said.
Bracing elements such as bolts and brackets were needed in many places to tie houses to their foundations.
"If there's lateral movement, your house could slide off the foundations and the foundations would just roll over without lateral bracing," he said.
Levick's North Shore-based business works mainly around Ponsonby, Grey Lynn, Herne Bay and Kohimarama and he estimates he's restored 200 houses and fixed dozens of residential and commercial structures with weathertightness issues.
"This one was mongrelised," he said of the three-level Devonport villa where he erected two new stair flights, opened up the main living, kitchen and dining areas and installed new heritage-style doors and windows on the northern face.
However, Connal Townsend, Property Council chief executive, is concerned about the Ministry of Building, Innovation and Employment's consultation document proposing changes to earthquake-prone buildings in response to the Canterbury Earthquakes Royal Commission final report.
The council had worked closely with the ministry throughout the process, providing consultation and as part of a sector reference group that first met in February to examine responses to the commission's findings.
He is concerned about how much landlords will need to spend to bring their buildings up to strength.
"The Government's indicative $1.68 billion cost is conservative. Property owners, already bearing huge costs because they can no longer claim tax depreciation for a building structure, will bear most of this," Townsend said.
Maurice Williamson, Building and Construction Minister, said events in Canterbury highlighted the need to review and improve our system for dealing with earthquake-prone buildings. The country had 15,000 to 25,000 earthquake-prone buildings, he said.
Victims' families said the new rules were needed, otherwise their relatives had died in vain. Had more stringent regulations already been in force, the quakes would have claimed fewer victims, they said.
Submissions on the Government paper close on March 8.