Waterproofing

There are so many waterproofing options and systems and its important to get it right the first time as its hard to get a second shot at it once the basement is done. For this basement Volclay sheeting was used behind the shotcrete walls for waterproofing.

Even with waterproofing in place its most important to have a good drainage system installed to stop the water pressure building up behind the walls.

Concrete feature roof

Here is a project I was fortunate to work on for mckimm, which involved building a concrete cantilevered roof structure over an outdoor entertaining area and swimming pool. 

The structure was built like a basement with suspended concrete slab as there is large concrete piling in the ground to hold the steel columns in place which supports the cantilevered concrete structure.

The concrete piling, steel columns and concrete upright walls were installed then the formwork placed for the roof structure. Skylights were placed as voids in the formwork and the lighting conduit plus fixtures installed with the steel reinforcing.

The concrete was vibrated, power trowel finished and sealed with a penetrating sealer for a smooth finish.

Polished concrete floors

Polished concrete floors look great but you need to be aware that concrete continues to shrink over its lifetime and cracks will appear. Set up of expansion joints is important and need to be considered in the design. Any heating and services need to be set up properly before the concrete pour.

The concrete mix can be any colour or type of stones you like, when the concrete is set you can not really tell how its going to look when finished as it looks like plain concrete.

Once the polishing starts thats when you can see the colour and stones. Polishing is done by grinding the floor using a polishing liquid and gradually using a finer grade grinding discs to create a smooth, polished and sealed exposed concrete floor.

Concrete BBQ

This bench was built out of concrete for the BBQ and Sink to be integrated with cabinetry to fit neatly underneath.

The steel starter bars were drilled into the concrete walls and floor with steel bar tied to it to form a self supporting structure, the boxing was then put in place to form a 100mm thick concrete slab. The concrete was placed and vibrated and steel trowel finished on top to form a smooth surface.

The boxing was left in place for 4 weeks while the concrete set fully, Then fitted with the appliances, cabinetry and finished.

Basement Plumbing

In the basement if its not done properly water issues can cause serious damage and ongoing problems. Its not only important to waterproof but also ensure the ground water behind the walls can flow without restriction and is able to be drained away.

Here we have placed strip drain in between the concrete piling, this will create the necessary void and drainage behind the shotcrete walls.

The drainage behind the walls and under the concrete slab need to be linked to a pump station which pumps the water to the legal point of discharge. 

Above you can see the stormwater pit we also have a sewer pit installed as there is a bathroom and wet bar to be build within the basement.

As well as having a large stormwater pit with dual pumps pumping water to the legal point of discharge we have a retention system also designed in the basement for those time when its bucketing down rain and the main drainage system within the street can not keep up with the deluge of water, this allows the water to back up with in the system and not flood onto the basement floor.