A court ruling about a children's fort is ensnaring a growing number of Wellington home owners in planning delays and extra costs.
Developers also stand to lose, with one predicting he will face $30,000 to $40,000 in unexpected bills for his new subdivision.
The fort in question, and a high fence, was put up between warring neighbours, the Aitchisons and Walmsleys, in the well-heeled suburb of Roseneath. It obscured the Aitchison's million-dollar harbour views. It was taken down last weekend - an Environment Court order made sure of that.
However, the toll from the wrangling over that court order has just kept going up.
Wellington City Council head of urban planning Warren Ulusele said some people with building projects on the go were now running into problems, and the numbers could only grow.
"It's quite possible that this could impact on any home owner where there is a retaining wall on the boundary and they are on a sloping site. The reality is many owners and developers may not even be aware that this has an impact on them."
In the hilly capital, there were thousands of properties that fitted the category Mr Ulusele described.
"The implications are potentially for the uphill property owner where they are far less able to undertake development on their site. In many cases residential properties could be reduced to one storey or even less," he said.
"We are dealing with a situation like that in a number of properties particularly in the northern suburbs, where there was an expectation a two-storey house could be built as of right, and now that may no longer be the case."
The court ruling in effect lowers the line above which you can't build near your boundary, unless you have resource consent, because it would cut too much daylight out of your neighbour's property.
This is most pronounced where slopes are steep and walls are high, because the line is now calculated from the bottom of the retaining wall instead of from the top.
Property developers react to change
Wellington property developer Wayne Wright was already counting the costs of the change.
"They are racking up all the time," he said. "I mean, right now could be between $15,000 and $20,000. If you add time delays in it, and obviously the inconvenience of me not being able to hand over a few homes maybe later this year when people were hoping to get into their new home, there's sort of a lot of other costs associated."
Mr Wright has 26 homes ready to be built in his Woodridge Development in Newlands.
Now he must go back and try to bundle them all up in a resource consent application that includes everyone signing to agree to let adjoining homes encroach on their daylight access plane.
One consultant who prepares consents for subdivisions told RNZ that developers and home owners might ultimately have to change their designs or shift where they built, leaving less usable garden.
Mr Wright agreed. "It's moving houses away from boundaries. Often the retaining walls are at the worst side of the section, let's say, so you generally put the retaining wall there and put your house as close to it as you can, and have the usable yard on the other side. So it's just pushing everything away from that boundary."
Another northern suburbs property developer told RNZ his company wasn't impacted as they made sure their retaining walls sat fully on one section or the other.
But Mr Ulusele warned the court ruling captured even a wall within 30mm of a boundary - so that northern suburbs developer could be in for a shock.
Worst-case scenario? A nasty neighbour could build a retaining wall within 30mm of your boundary but entirely on their own land, and then kick up a fuss about not just your extension plans, but your existinghouse encroaching their daylight access plane.
To waylay all of this, the city council is asking the courts to let it carry on an appeal against the Environment Court ruling.
If in the end it loses, it will have to undertake an expensive and lengthy district plan change to get back to how things were before that troublesome fort in Roseneath went up.