People often want toilets and other plumbed facilities in their backyard pods. Sewerage isn’t handled by magic, yet the cost of achieving compliant sewerage connections is often overlooked at first when a granny flat or home-office with powder room is being planned.


Sample sewer diagramStart by getting a copy of the Sewer Service Diagram for your property. You can probably do this online. On the right is a copy of a Sewer Service Diagram (Sydney Water) recently obtained online by a customer.

The property concerned is #30 and the black rectangle indicates the approximate position of the proposed pod. The main sewer line runs along the rear border of the adjoining properties. To connect the bathroom of the proposed pod by conventional methods (subject to approval), a large trench would have to be dug across the backyard, and a 100mm sewer pipe would have to be laid/buried – flowing downhill.

For the example shown on the diagram (#30), where the backyard is open lawn area, there are no trees, and the land slopes gently in a favourable direction, the cost of backyard excavation/sewerage works alone has been estimated at more than $3,000.

At some properties where there are obstructions such as inground pools and expansive concreted areas, or where the block slopes in an undesirable direction, quotes for excavation/sewerage works can exceed $10,000.

If getting your sewerage connection sorted will be relatively straightforward, no worries.

But if you’ve got issues that could cost lots to resolve, you might want to look at any alternatives out there. Remember, any works relating to water/sewerage/gas have to be carried out by a licensed plumber.

Composting toilets

We’re often asked: “Can I put a composting toilet inside a pod?” and the answer is: “Theoretically, of course, you can.” Just follow the manufacturer’s instructions for non-slab installation or get it installed by someone the manufacturer endorses. But before you go too far down this track, you’d need to find out if it’s okay to have a composting toilet in your local area. Ask someone at your local Council if you can’t find guidelines online.

Saniflo macerator/pump systems – Sanicubic 1

This innovative system can sometimes halve the cost of sewerage-related works where there are issues preventing a straightforward sewerage connection.

Sanicubic 1 by SanifloThe Sanicubic 1 pumping station is designed to accept multiple fixtures from the bathroom, kitchen, and laundry. Toilet waste can be macerated into small particles and combined with other wastewater to flow through a standard 40mm pipe (not the usual 100mm pipe required for sewerage). Wastewater can be pumped up to 11m vertically or 100m horizontally, or a lesser combination of both. The connection can be made into the main 400mm wastewater pipe system at the nearest access point, from where the combined household wastewater ultimately flows to the sewer.

You can talk to us about Saniflo. Download brochure on Sanicubic 1 here.