However, the Government said the regulations were inconsistent and "often cumbersome", and changes were needed.
These will include:
• No longer requiring spas and hot tubs to be fenced off if they have a lockable cover and meet certain specifications.
• Require councils across the country to carry out five-yearly inspections of swimming pools.
• Make infringement notices the preferred way to deal with pool owners who fail to comply, with court prosecutions only in serious breaches.
The current law allows spa owners in Auckland to apply for an exemption from fencing if their spa has a lockable cover - but that costs $455.
About 270 spa exemption requests were made to Auckland Council last year.
In Parliament today, National MP Craig Foss, speaking on behalf of the responsible minister, Building and Housing Minister Dr Nick Smith, said the current regulations had reduced drownings, but were a source of frustration for many.
The law change is expected to improve safety, but also reduce compliance costs by $17 million, Mr Foss said.
The changes are similar to those proposed in 2013. However, a proposal to reduce the depth from 400mm to 300mm for triggering fencing requirements has been scrapped.
That change was designed to strengthen the safety message that people should empty temporary portable pools after each use.
Pools containing less than 300mm of water are normally practical to empty after each use, and such a threshold would match regulations in Australia.
However, when the proposed changes were announced in November 2013, there was some backlash against the idea that paddling pools would require fencing.
A regulatory impact statement notes that councils would have struggled to enforce such a change, and owners of affected pools would be unlikely to comply.
"We do not expect [a 400mm depth threshold] would lead to a significant increase in the overall risk of young children drowning in pools, because we expect the increase in the use of pools between 300mm and 400mm of water would be small relative to the total number of portable pools," the regulatory impact statement, produced by the Ministry of Business, Innovation and Employment, concluded.
A spokeswoman for Dr Smith said the 300mm depth threshold would be overly burdensome for pool owners, and there was insufficient evidence that a depth reduction was required.
"No body of water, even 50mm deep, is risk-free but Dr Smith is satisfied that there is insufficient risk between 300mm and 400mm to justify the fencing requirement for paddling pools that are easily emptied after each use."
Barry Smedts, Auckland Council's manager compliance for building control, said the law change was a "long awaited step that has been requested by territorial authorities and judiciary for many years".
The council currently inspects pools every three years, and has about 33,000 swimming or spa pools on its register.
The Building (Pools) Amendment Bill will now be heard by select committee.
