Additions, extensions and alterations

The latest edition of Owner Building in South Africa gives new insight into planning and managing projects, from small alterations and additions to building your own home. We publish an extract from it.

Undertaking a major extension can be as complex as building from scratch. When you plan your home, it is a good idea to consider the possibility of future expansion, and make provisions in your initial plans. Clever planning can limit the amount of future demolition work that may be required.

For example, where you might want to add a door, build in a lintel and enclose the door area within straight joints in the original building. This will make it easier to break out later on.

Apart from lateral extensions, options for creating extra space include adding an upper floor, building an extra room over a garage or converting unused roof space into a habitable attic or loft.

Before you begin any alterations, check with your local authority whether plans are required. Even if you only undertake 'minor building work' as defined in the building regulations (such as opening up a wall to put in a sliding door or enlarging a room by demolishing an internal wall), some councils will insist on working drawings although, in most cases, these will be readily approved.

The National Building Regulations state that local authorities are permitted to exempt additions and extensions to single storey buildings from the new requirement relating to the appointment of a 'competent person'. However, the building inspector must be assured that the existing foundations were built according to the relevant standard and that there is neither excessive cracking nor any possibility of future cracking.

Additions and alterations
Additions (including simple extensions) and alterations (which can be straightforward or quite structural and complex) should always blend with the established style of the house and not be immediately noticeable as extensions.

Give careful thought to the design of any addition or alteration and try not to look at it in isolation. Look at the property as a whole, bearing in mind that details such as proportion, paint colour, brick finish and so on are all relevant. If you do add to the house, either now or later on, you will need to match them.

Structural alterations tend to be expensive, although you can make substantial savings if you plan for future extensions in advance. It is often more economical to extend a house, by adding another room for instance, rather than trying to change the structure of an existing home or add on another storey.

Matching new materials to older ones is often problematic. There is frequently a tone variance, even if you are using the same product. For instance, although new roof tiles may be the same colour (even from the same batch, if you kept extra tiles when you first built), the original tiles will have faded over the years.

However, over time, the new tiles will also fade and, hopefully, become indistinguishable from the older ones. The shape and dimensions of materials can change over the years. For example, older, tin-roofed homes might have been built using imperial-size corrugated iron sheets, so the metric profiles that are available today will be quite different.

Bricks and wall tiles are also subject to similar variations in size and shape. If you cannot match old materials satisfactorily, then consider opting for a complete contrast; for example, adding a timber frame extension to a face brick dwelling.

Read the full article on page 22 of the August 2012 issue.