Altering character houses/buildings

There are many things to consider when extending or renovating a character house or building.

Creating more space

Many owners of character houses will want to extend the property at some stage to provide additional indoor and outdoor living space.

Extra space was traditionally achieved by enclosing verandahs, and more recently by building in underneath, extending, or constructing a linked separate building.

However, alterations and additions should be done in a way that is simple and sensitive to the form and character of the original building. The house and streetscape may change for the worse if inappropriate roofing materials / profiles are used, verandahs are closed in, or chimneys, windows and joinery are removed.

Building underneath the house

Using existing space underneath

  • a successful extension will ensure the building's appearance and proportions remain as close to the original as possible
  • for aesthetic reasons and practical reasons like waterproofing, external walls of the lower level should be one row of stumps back from the external walls or verandahs of the upper level
  • retain or reinstate the original external front steps and extend them if required
  • ensure new perimeter stumps are of a similar size, shape and material to the original stumps.

Raising the house

  • consider whether raising the house is the best option, as this generally results in a substantial change to its appearance and scale
  • consult the Building Code of Australia to check the height in the underneath area (habitable rooms will require a minimum 2.4 metre ceiling height)
  • if possible ensure the building is raised no more than an additional 800mm
  • if the building must be raised more than 800mm, excavating should be considered as an alternative, providing there is adequate waterproofing and drainage and that underground sewer lines are not disturbed 
  • partial excavation is preferable to significant house-raising (>800mm) as the proportions of the house and its relationship both to the ground and to the street is maintained
  • make sure building in work is set back by at least one row of supports from the front of the building, to allow battens between the external row of stumps to remain or to be reinstated   
  • retain timber stumps around the outside of the building or replace them with matching treated timber stumps, not steel posts   
  • do not introduce unsympathetic building materials, such as aluminium framed windows and ensure new work is compatible with the original external wall material
  • use timber battens and timber-framed walls to maintain the lightweight look of a timber house.

Houses on sloping sites

  • minimise the impact of raising a house by excavating into the hillside, but ensure surface run-off and seepage moisture are adequately addressed
  • keep soil clear of the external building walls to reduce the risk of termite attack and so water can be diverted away from the house
  • protect masonry retaining walls with a waterproofing membrane and back-fill with gravel to divert seepage into an agricultural drain.

Building on to the house

Adding an extension

  • make the new work sympathetic but do not try to mimic the style of the existing house
  • build at the rear to maintain the streetscape presence of the character house
  • distinguish old from new minor extensions by setting back the new wall line a minimum of 500mm from the existing wall or create a clear visual break, such as an expansion joint, changes in wall cladding, a recess or a full-height opening.

The pavilion extension is a highly recommended way of increasing the size of a traditional house. The pavilion extension, although occupying yard space, allows for the retention of the original form, its relationship to the ground, and the streetscape character of the earlier building. It enables modern facilities and lifestyle preferences to be incorporated into the new extension.

The connecting link also allows for cross ventilation while providing a pleasant semi-outdoor transition from the old to the new parts of the building. Connecting the new extension to your building in this manner also represents best-practice principles of Subtropical Design.

For more information and case studies, developed by the QUT Centre for Subtropical Design, visit the QUT website.

Inappropriate extensions

  • inappropriate use of materials such as masonry as opposed to lightweight construction
  • extending into the roof to create more space or to take advantage of views
  • extending the form of the building without a clear visual break
  • additions which overhang the existing building
  • additions which significantly alter the shape and character of the original roof.

Adding a deck

  • design the deck so it complements the original house
  • locate the deck at the side or rear rather than in front to preserve the character and presence of the house in the street
  • carefully consider the roof form over the deck.  It should complement the the form of the main roof.

Building in other locations on site

Moving a house

  • discuss options with Council as any building proposed for vacant land in a Traditional building character overlay or Character residential zone will be assessed on how it impacts on the streetscape character
  • do not subdivide or shift a building to one side of a large allotment to accommodate new development without checking with Council as outbuildings, garden, fences and the landscape setting may also constitute an important part of the character of the area.

Building a carport

  • consider building a single garage in conjunction with an open carport rather than one very large garage
  • ensure the carport design does not dominate the street frontage
  • locate the carport at the rear of the site, if possible or where it does not block views or detract from the street and landscape character.

Further reading

  • Evans, Ian, Getting the details right: restoring Australian houses 1890s-1920s, Flannel Flower Press, Yeronga, Queensland, 1989
  • Evans, Ian and National Trust of Queensland, The Queensland House: history and conservation, Flannel Flower Press, Mullumbimby, 2001
  • National Trust of Queensland, 'Planning alterations', Conserving the Queensland house, Brisbane, 1995 (guide 10 of 12)
  • Townsville City Council, 'Heritage Information Kit, 2004

You can download images of examples of altering a character house or building (Word - 2.1Mb).

If you wish to find out more, Council's fact sheet Heritage and character buildings can provide additional information. You can also contact Council's Heritage Unit.

16 September 2014