Earthquake strengthening: This will involve new piling and foundation walls for much of the House and ensuring the foundations are properly connected to the building. More than 35 walls will be exposed and strengthened with structural steel braces. Additional steel frames will be added to strengthen the roof and tower. The deteriorating stone columns will be replaced with Oamaru stone faced steel columns.
Improved access for people with disabilities: Improved access will be provided at all entrances for people with disabilities. Two lifts will be installed to provide access to all levels.
Weathertightness: The roof, associated flashings and battens will be completely replaced with new tiles affixed with rust-resistant stainless steel nails. The stucco panels will be replaced or repaired where necessary. All the doors and windows will be better sealed to reduce draughts - a major source of heat loss in the building.
Modern services: The outdated and ageing water, wastewater, stormwater, power, gas and communication services will be replaced. The inefficient heating and lighting systems will also be replaced and elements of environmentally sustainable design, such as solar water heating, air source heat pumps, high efficiency boilers, floor, wall and ceiling insulation, rainwater collection and low energy use appliances will be introduced along with a building management system. The fire protection systems (smoke detectors, sprinklers and smoke control doors) will also be upgraded.
Improved exterior layout: The driveway will be repaired and reconfigured to emphasise the main entrance while the porte cochere (cover) over the main entrance will be extended to allow modern vehicles to enter and leave more easily. Access to the House for people with disabilities will be improved. Better access will be provided from the north lawn to the terraces that lead into the House.
Enhanced heritage values: The chimneys that once dotted the roofline will be reconstructed, as will the hoods that once protected the windows. The windows will be reglazed using low - E security glass and the lead lights will be reintroduced. Many non-original doors and windows and exterior pipes will be removed. The deteriorating exterior pillars will be replaced with new Oamaru stone faced steel columns. The House will be repainted in colours that better match the original colour scheme.
Improved internal layout: The Governor-General's staff will be moved to offices in the west wing with direct access to Their Excellencies' offices. A distinct office entrance for staff and visitors, away from the formal entrances, will be created. The finishing kitchen next to the Ballroom will also be upgraded.
Improved privacy for the Governor-General and spouse: The Governor-General's suite will be reconfigured into a self-contained apartment that includes a kitchen and which is separate from the main hallway. The rooms of the two Aides-de-Camp (military) officers will be moved to be closer to those of the Governor-General.
Improved standards in the guest suites: The eight guest suites, used by visiting Heads of State and other important visitors, will be renovated with modern technology and private en-suites. Furnishings and fittings will be replaced where necessary and security and modern communications systems introduced.