Subiaco-based barrister George Papamihail, who bought the site at 257 Adelaide Terrace last October for more than $5 million with a business partner, is planning to build a 13- storey office tower, containing 6,000 square metres of office space.
Under the current designs, the two storey heritage-listed house, which was placed on the state's permanent heritage register last year, will be retained, connected to the new office tower at ground level.
A walkway will also join the two buildings on the first floor.
Architect Sam Fardoe, who prepared the designs for the site, said the intention was to convert the upstairs area of Adelaide House to offices, with the ground floor suited to a cafe or restaurant.
A forecourt open to the public will also be built.
Mr Fardoe said very little of the original building would be changed, with $1.5 million having been spent on restoration.
"We have to retain the house, so we've created a colonnade through the ground floor by removing an additional staircase that was built in the 1950s," he said.
"In the new building, we're trying to make use of the natural light and while we're not currently seeking a green-star rating, we are looking to use sustainable design principles." Describing the office tower as a post-modern interpretation of Adelaide House, Mr Fardoe said the new building would mimic elements of the original, having balconies instead of a two-sided verandah.
"The owner said he wanted [the new tower] to look like the old building, but on a bigger scale," Mr Fardoe said.
"His favourite TV show is Boston Legal, and I think he has visions of himself sitting on the bullnose verandah, smoking a cigar." The project is the latest in a series of new office developments planned for Adelaide Terrace, following the approval of Finbar's 15-storey office tower on the Fairlanes Bowling site last month.
Another site which would lend itself to an office development, at least in part, is the old ABC studios site, which is for sale.
The site, which is also partially heritage-listed, is expected to fetch upwards of $50 million.
Next door to the Adelaide House site, Stockland is building a $34.5 million, five-storey office tower behind the Durack Centre.
