Renovation and Home Design

Overflowing Drains

Overflowing drains

Its not unusual to see local flooding around a house, or on streets, during exceptionally heavy rainfall.

If you are unlucky you might even see a manhole ‘Pop It’s Top!’ like this one!

This is because the council drains don’t have the capacity to deal with these really heavy rains!

Why It Happens

The roof [read more…]

Temporary Down Pipes

Temporary downspout

A great way to stop the building site from becoming water logged is for the builder to install temporary down pipes as soon as the roof has been covered.

Although this is generally good practice it is really important if you are building on Reactive Clay as it will minimise the occurrence of Soil Heave [read more…]

Silt Pits

silt pit 2

Any drainage system should have silt pits at regular intervals.

This includes both stormwater systems and agricultural drains.

In the case of the above photo this is a combination drain and grate silt pit. (As the water can become stagnant this is a potential breeding ground for mosquitos!)

The pit may be either circular or [read more…]



In Western Australia you are required to dispose of storm water on your block, rather than to a public storm water drain.

There are also many areas that don’t have public stormwater drains including many beach side areas.

In either case if this applies to your block then you will probably need soakwells, so here [read more…]

Soil Heave – Protecting the Slab During Construction

Protecting slab Stage 1

There has been a lot of talk in the Melbourne papers recently about ‘Slab Heave’ when Building on Clay so I thought I would explain how to minimise the risk during construction.

A key issue when building on clay is to avoid any extra moisture getting into the clay under the slab. causing the clay [read more…]

Stormwater Discharge Point

Heavy rain

One check that is often forgotten when buying a house block in an established suburb is how storm water is removed from the site.

Forty, or more, years ago when land was cheaper, it was not unusual for blocks to be quite large compared with the size of the house.

Disposing of storm water [read more…]

On-Site Stormwater Detention – Storage

conctrete detention tank


Many urban developments, and subdivisions, require stormwater flows from your block to be limited to a maximum flow rate. (See: ‘Onsite Stormwater Dention‘ for the reason why)

Although councils will require the calculations to be done by a qualified hydraulic engineer here is some explanation of the process so you can understand what is [read more…]

Onsite Stormwater Dention – Why


If you want to redevelop or subdivide an existing urban house block, you might find that a planning condition is that you will need to provide On-site Stormwater Detention (OSD).

You may also find it is a condition on individual blocks on smaller subdivisions.

Why Is Onsite Stormwater Detention Needed?

Before development of towns and [read more…]