More than half of our projects are house alterations. In Wellington, new building sites are rare, so our clients with growing families are choosing to modify their own house to gain an extra room or two, extra storage space and some re-planning of the existing spaces to create a more functional and warm family home. Though we have completed a few alteration projects in Auckland and the Hawkes Bay, most are in Wellington where the topography is varied and usually steep, requiring different approaches. There are however some recurring themes that categorize projects as follows:
Original villas & bungalows and state houses from the 40s-60s are mostly well-planned with logical circulation and layout of rooms, however they often have the living spaces on the south side which means they are cold and dark. Later speculative housing tends not to be well-planned and most houses, regardless, have suffered from poorly designed alterations and additions over the years. With some careful re-planning to eliminate unnecessary circulation space, a huge difference can be made to how the house functions. Also, Velux skylights on the north or west side of a roof can greatly increase the inside temperature through solar heat gain.
Extending the footprint
If the land is available this is typically the most cost-effective solution to increasing the size of the house. Whether it is a single level or multi-level extension, building outside of the existing footprint means you can effectively build new from the ground up which is considerably easier as it avoids a lot of time-consuming adjustments to existing structure to insert new elements such as doors, windows, posts, beams etc.
Extending into the roof space
This can be the only option where there is no land available, site coverage is already maxed out, or a reduction in the outdoor space not desired. This approach is quite involved as it means inserting a whole new floor structure with posts through walls and new foundations. A stair will also need to be accommodated somewhere in the main circulation area which takes up space. The overall appearance of the house and any effects on neighboring properties has to be carefully considered. If the existing roof has enough height, we try to keep the ridge line in place and have dormer windows which preserves the look of the house, particularly if it is a traditional villa or bungalow. The main advantage of an upper level extension, if the situation permits, is the sun and outlook from the new rooms, and the new stair can be used as a way to bring light down into the centre of the house.
Extending below the floor
Many houses in Wellington are on sites that slope either up or down from the street. This means that a standard house plan has a basement area below, at the front or back, for roughly half the footprint. This presents an opportunity to build out below the house and utilize this extra space. Like a roof-top extension a lower level build-out can be relatively expensive as it involves excavation and removal of earth and construction of waterproof, below-ground concrete walls. Generally these spaces are not as light, but depending on the property, can provide great access to a garden or create a new entrance that is closer to the street.