The Vincent Community Board considered a report on the matter last week and agreed money should be set aside in the draft annual plan for the upgrade.
It was told a single tender had been received for the project, and reducing the scale of the work would amend that to $214,926.
In his report to the board and the Central Otago District Council, Dave McKenzie, of DM Property Solutions Ltd, said the roof insulation acted as both insulation and a vapour barrier.
During construction of the pool, the original plan for two layers of insulation was changed to one layer.
Two sides of the insulation were glued together but since then, roof thermal expansion and contraction had caused the glued joints to split open, compromising the pool's vapour barrier, Mr McKenzie said.
The pool's environment was kept at 28degC and 85% humidity and warm, moist air had been getting though the gaps in the insulation and causing condensation on the underside of the roof iron, similar to condensation forming on exterior windows when a shower was running.
The condensation then dripped down on the insulation and ran back on to the top side of the pool ceiling and acoustic panels.
''The water runs down the acoustic panels and rains down on the side of the pool,'' he said.
Because of the excessive condensation, the pool roof space was wet and would deteriorate quickly if the problem was not sorted out, Mr McKenzie said.
The only long-term option was to seal the gaps in the insulation, add another layer of insulation and provide a layer of building wrap between the insulation and the underside of the roofing iron.
Board chairwoman Clair Higginson said the project was estimated to cost $90,000 more than what was originally budgeted, which was ''quite a lot of money''.
However, the board had little choice other than to get the work carried out.
Council corporate services manager Susan Finlay said the extra cost would have a minimal effect on rates but would have more of an effect on reserves, on the investment account.
Board member Barrie Wills said it was a pity it was ''not done properly in the first place''.
Fellow board member Stu Millis said cutbacks were done when the pool was built ''and this is probably part of it, but we have a good facility there now''.
He suggested the council ''float it [the project] in front of a few people again'' to see if any other tenders were received.
Mr McKenzie said if the council opted for the sole existing tenderer, work could begin in September.
The part of the pool directly under the roof area being worked on each day would have to be closed, but the rest would remain open.
The work was expected to take between 10 and 18 weeks.
