RESTORATIONS of the historic Plumb's Chambers are progressing steadily, despite some surprising discoveries along the way.

Queensland property developer McConaghy Group said the $1 million restoration of the Fitzroy St building had been going well since February.

Stonemasons on the site have given way to plumbers and electricians who have completely replaced the building's electrical wiring and plumbing.

The electrical work on the site has been handled by local electrician Harold Byrne, of Harold Byrne Electrical.

Mr Byrne and his crew of three have completely replaced the electrical and data works for the whole site, including the incoming supply and main switchboard.

He said that because of the dilapidation of the building, electrical supplier Ergon had refused to even turn the power on until it was repaired.

"Ergon could not even get to the meter box which was on the front veranda," Mr Byrne said.

"They made the decision that they would not be going in there."

Mr Byrne said that because the wiring was in a state of complete disrepair it had to be effectively installed from scratch.

"Everything will be completely brand new, including the mains supply from the mains box, all the way through," Mr Byrne said.

"There will not be a single bit of electrical that was in there beforehand that will be used again. It's a complete new installation as far as electrical wires."

The plumbing for the building, which has been handled by a four-man team from local plumbing firm 2S Plumbing Solutions, has also been entirely replaced.

Owner Shannon Cameron said the renovation had brought unusual challenges for a plumber used to working on relatively modern buildings.

"The main challenge we face is trying to bring in the new plumbing standards while being restricted

within heritage rules," Mr Cameron said.

"It's things like guttering and downpipes and little things like heritage vents.

"We need to keep the old galvanised vents in place but still have to adapt that to our new drainage underground."

To protect the stonework from rising damp, high-tech Newtonite waterproofing membranes were imported from England, allowing the stone to breathe while also keeping water out.

"Some of the obstacles we've found there, such as a natural spring quite close to the surface, have dragged it out a bit and we now have to try and come up with a solution," Mr Cameron said.

"These are things you just don't know of until you start excavating."

McConaghy's site manager John Adams said the biggest cause of damage to the building had been white ants which had devoured most of the internal timber.

"I've never seen so many white ants in my life," he said.

"Everyone we've spoken to - the council, the heritage people who've been out here and seen what we've shown them - they couldn't believe how white ant infested this building was."

Mr Adams said that as they peeled away the layers of decay, the size of the job had continued to grow.

"It's the amount of unexpected work and trying to make something square out of something that is just not," he said.

"We certainly have quite a bit still to complete."

Where possible, Queensland timbers have been used to replace the woodwork throughout the building.

One exception has been the lintels, where appropriate timber could only be found in northern NSW from the remains of an old bridge.

One thing that everyone involved in the project agrees about is the pride they will feel when this important piece of Warwick heritage is restored to its former glory.

Site foreman Josh Berryman said that as the building's external appearance had improved, his friends and neighbours had noticed.

"Every day we hear something about the building and nine times out of 10 it's all positive now," Mr Berryman said.

"People are starting to see how the building is shaping, and with a lot of locals working here on the site, it's drawing an awful lot of good attention."

Mr Berryman said that like most tradesmen in the local area, he had done a wide variety of work from houses to high-rises and hospitals, but Plumb's Chambers was a completely new experience.

"Everything we deal with is just not seen or heard of," Mr Berryman said.

"The way they did it 100 years ago is a lot different to how we normally do it today.

"Everything we're doing is just the way it was done 100 years ago. The veranda is all mortared and tannined and trying to find tradesmen to do that is near impossible today too."

Mr Byrne said his work would be a source of pride for years to come.