Common oversights during home construction as an owner builder

Timber floors

If you are laying a wooden floor in your home, pay special attention to the sub-floor ventilation. Any dampness trapped under the house will rot out the bearers, joists and the wooden floor itself. Adequate ventilation by way of vents is required and always ensure these are not blocked off by garden beds or paving.

Electrical, Data and Telephone Wiring

The best time to install electrical, data and telephone wiring is at the framing stage. The electrician will need to rough in the wiring and fit base plates. The data and telephone cabling should be fitted at the same time. Try to fit wiring after plastering will prove difficult and expensive.

Sit Set Out

No construction can begin until the site has been set out. All lines must be square and correctly aligned to the boundaries. While experienced contractors and builders can do this, an owner builder is advised to utilise the services of a building surveyor. Mistakes at set out will become evident during construction and may end up becoming a disaster if not corrected and rectified early on.

Brickwork

If using bricks in the construction fabric, choose them carefully. Clay bricks come in many varying shapes and sizes. Concrete bricks come in plain or coloured and may be the better choice if painting, bagging or rendering.

Bathroom

Wet areas require special attention. Water leakage from the shower constitute approximately 80% of building complaints and can cause rotting. Ensure your plumber has correctly sealed shower bases and other fittings. Use CSIRO approved membranes - a list is available from the CSIRO website.

Concrete slab

If your construction method incorporates a slab on the ground, the correct waterproof membrane fitted beneath the slab is vital and mandatory. Be sure to have the membrane turned up around the edges of the slab and protected from the UV rays of direct sunlight. Without a correctly fitted membrane, the slab would never fully dry out resulting in dampness problems, particularly to floor coverings.

Delivery of materials

Materials delivered at the wrong time can cause problems. It too late, delays will occur. If materials are delivered too early, you may need security against theft or wet weather. Deliveries need to be carefully scheduled to coincide with the trades on site. Discuss material needs and timing directly with the individual trades.

Drainage

It is very important to keep moisture away from the construction. Once completed, the house will need a hard surface around the base to divert water away from the building. This can be made from concrete or paving and care should be taken to ensure the skirt slopes away from the outside of the house.

Records

Keep records of all labour and materials payments for good taxation and budget control. Written records of any instructions or variations to tradespeople or contracts will help reduce the likelihood of disputes. Remember to get the tradespeople or supplier to sign a copy of any written agreement.

Footings

Footings will be the first structure installed in the building process for houses with timber floors. Footings are reinforced concrete poured into prepared trenches and it is the responsibility of the owner builder to ensure that the trenches are the correct depth, width and that the trench sides/floor are straight and level. Trenches are usually dug by an excavating machine and may need to be finished up by hand.

Inspections

As the owner builder, it is your responsibility to arrange the building inspector at the critical stages. Inspections are usually required at the footing, framing and final stages. Contact your local council or building surveyor at the permit application stage to confirm which and when inspections are needed and program them into your schedule. Mandatory inspections do not cover every part of the construction process. It is strongly recommended you engage a building inspector to conduct extra inspections to ensure the works are up to industry standards.

Material storage

The materials purchased for the project are expensive, so it stands to reason that protecting them is a crucial part of your planning process. Materials left out in the rain will weather and if not stacked correctly, will damage or get in the way if left lying around. If vulnerable materials have to be left outside, consider building a shed to house them or cover them effectively with weatherproof tarpaulins. Theft of materials from job sites is a major industry problem. Never leave valuable tools or items exposed and if possible, keep them under lock and key.

On-site services

Electrical power and temporary toilet facilities are required during the entire construction process. Arrange for the early supply of temporary power facilities and a portable toilet for all workers. These can be hired from specialist hire companies.

Housekeeping

Site cleanliness and maintenance are serious occupational and safety issues. Keep the building site free from off cuts, broken and excess materials, wrapping and rubbish. Most building projects will require up to 6 large rubbish skips for rubbish removals. Proper housekeeping will reduce the risk of injury and increase the productivity of all workers and contractors on site.

Variations

It is the responsibility of the owner builder to ensure the construction follows what is allowed in the building permit. Variations are allowed, but these will need to be referred back to the authority that issued the building permit. This should be done in writing, explaining the changes and accompanied by a clear diagram of the variation to the building plans.

For more information about owner building or if you require owner builder finance, speak to the mortgage brokers at Intellichoice on 1300 55 10 45.