Plumbing and drainage

Common problems include low hot water pressure, leaking drains, and corrosion of original pipes.

Original details

Original villas would have been built with on-site storage tanks, with the overflow going to soak pits. 

Drainage and sewerage services often came as a combined system where the same pipes drained stormwater and sewage. Most have now been separated.

Water supply

Large galvanised corrugated iron water tanks were available from the 1880s. They were used to collect roof rainwater. Water was generally piped by gravity feed from the roof to the tank and from the tank to the laundry and scullery sink only. Rainwater tanks were mounted on timber stands, below the roof line, but sufficiently high to provide some head at sink-bench level.

From the 1860s, piped mains water was available in main city centres, but it wasn’t until the 1880s that supply was provided to housing. Early piping may have been to scullery and laundry only, but may include supply to the wash hand basin and bath.

With the introduction of the flushing toilet at the turn of the century, sewerage and – just as importantly – the reticulation of town water became important. Town water then served most outlets in the house, with the exception of the laundry tubs which continued to use rainwater into the 1940s and 50s.

Water heating

Coppers were the first form of heating water and were usually located in an outbuilding. These larger containers held about 60 litres of water and were permanently mounted on a concrete or brick stand. A fire was lit underneath. Clothes were washed in very hot water in the copper. The coal range provided the initial means of water heating inside the house. 

From 1870s, the gas califont could be used to heat water if running water was available. Some housing in the early 1900s had a gas califont over the bath. However, califonts were not common.

In 1915, the first water storage heater was developed by Tauranga Borough engineer Lloyd Mandeno; this was patented in 1923. 

By 1946, 32% of homes had electric water heaters. For the villa, the hot water cupboard became the first built-in cupboard, often placed into the bathroom when it was upgraded with a modern bath, hand basin and flushing toilet.

The use of the copper continued through to the 1930s to heat water for laundry washing. They were replaced in the 1950s with the introduction of the washing machine with hot water reticulated from an electric or gas storage heater.

Pipes and drains

Early water reticulation was by ½–1” (12–25 mm) galvanised steel pipe with screwed connections. Over time, a combination of rust and other sediments would build up and restrict the flow. 

Original stormwater and sewage drains would have been terracotta or, in some situations, cast iron.

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Many villas would not have had water reticulated within the building, except to the sink within the scullery. The addition of bathrooms and improvements to kitchens required the addition of new piping as an early modification.

With the inclusion of newer sink benches, bathrooms and especially with the introduction of electric hot water heating and storage, extensive replumbing is likely to have occurred.

Much of this was in steel pipe – PVC and polybutylene not becoming available until the 1960s.

Much of the original galvanised steel pipe is likely to have been replaced by polybutylene or copper. 

Original, low-pressure hot water cylinders are also likely to have needed replacement – usually with another low pressure system unless a total remodel has been carried out.

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Common problems and remedies 

Corrosion of original pipes

If original galvanised iron piping remains, it is likely to be in poor condition due to corrosion (internal corrosion can restrict flows through the pipes) and in need of replacement. 

Low water pressure

While early hot water cylinders are likely to have been replaced, often this was with another low pressure one – so hot water pressure within villas is often poor. Old, corroded pipes will also reduce water pressure. There is often insufficient pressure to run modern bathroom fittings such as showers.

During renovations, there is the option to convert the hot water system to mains pressure, provided any retained pipework and fittings will cope with the additional pressure. It may be necessary to also replace bathroom and kitchen fittings.

Damaged terracotta drains

Over time, the joints in terracotta sewer and stormwater drains are likely to have become loose and leak. Pipes may have cracked, perhaps because of tree and plant roots seeking out the water from the drains.

Uninsulated hot water system

The 2015 BRANZ House Condition Survey, involving over 500 houses, found that two-thirds of hot water pipes were not insulated – this equates to over 1 million houses across New Zealand. Retrofitting insulation to hot water pipes where practicable is a good idea.

Overall, 79% of cylinders that pre-dated 2002 (34% of all cylinders) had no cylinder wrap. This equates to just under half a million houses. The government’s Energy Efficiency and Conservation Authority (EECA) recommends adding a thermal wrap around cylinders manufactured before 2002.

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Who can do what?

Relatively simple plumbing jobs such as connecting up a washing machine or replacing a tap can be done by competent householders, but there are rules around who can do other types of work. Sanitary plumbing – work that involves water supply pipes or waste pipes, traps, ventilation pipes or overflow pipes – must be done by a licensed plumber. You can find more details here.