New life for old polystyrene

Reusing the waste polystyrene, which invades our shops, homes and garages can solve huge problems at the landfill.
Polystyrene is light but is hard to dispose of. It is toxic to burn, and very bulky in the landfill.

"Polystyrene can be easily reused, it can provide valuable insulation for new homes when encased in concrete"

"A safe place for reformed polystyrene domestically, is firmly encased in concrete."

- Alan Fielding, PNCC Zero Waste Strategy Leader.

Using polystyrene pods as under floor insulation means less excavation is necessary, there is less construction time and less soil to remove.

When a conventional slab cannot be laid because of weaker soil types, Polystyrene under-floor pods can make a huge difference. The need for piling can be significantly reduced or removed completely, depending on the location.
Less excavation means less excess soil to be removed. The hard slog of digging the external edge beams is also either removed completely or significantly reduced.
Spacers made of recycled plastic hold the polystyrene pods apart. Rienforcing steel mesh goes over the pods, and is wired securely together prior to the concrete being poured.

The total energy savings to the occupants of a polystyrene insulated home are huge. A pod floor has much greater insulation than concrete alone. Constructing a polystyrene insulated floor is quicker than a conventional concrete floor and it is stronger. A pod-insulated floor takes daytime heat and releases it in the evening. You'll have better health and a better standard of living with better insulation. Using pods in your new concrete floor removes polystyrene from the waste stream for the lifetime of the house. When we recover and recycle polystyrene it creates employment opportunities from waste.

Wilton Joubert Ltd is pleased to be associated with Polyreform Ltd, in the reusing of waste polystyrene into under floor insulation.

Wilton Joubert Ltd is the most experienced concrete and polystyrene pod slab designer in New Zealand, and is able to design a residential floor slab or foundation to suit the most difficult sites or ground conditions. Our design service includes providing a specific design, PS1 producer statement and detailed drawings for construction of polystyrene pod floor.

WJ 100 & 101 - Raft Spacer System

WJ 100 Centre Spacer Fig 1.

WJ 100 Centre Spacer Fig 2.

WJ 100 Centre Spacer Fig 3.

WJ 100 Centre Spacer Fig 4.

What can these raft spacers be used for?

There are two spacers in this series, the WJ 100 Centre spacer and the WJ 101 Clip-on spacer. They can be clipped together to form a variety of combinations.

• The WJ100 Centre spacer is designed to form 100mm wide internal ribs.
• Slab thickenings or internal beams can be formed in multiples of 100mm by adding WJ 101 Clip-on spacers to the Centre spacers.
• The Centre spacer naturally creates a 200mm edge beam. The edge beam can be increased in multiples of 100mm by adding WJ 101 Clip-on spacers.

Reinforcing placement

• A single reinforcing bar can be placed in a 100mm internal rib and two bars can be placed in a 200mm edge beam. An extra reinforcing bar can be added for each WJ 101 Clip-on spacer that is added.
• The WJ 100 and WJ 101 spacers have been designed to allow for the following concrete cover: 50mm bottom cover, 45mm internal cover to polystyrene and 75mm cover to external surfaces.

How many spacers do I need?

For the basic system with 100mm internal ribs and 200mm edge beams, calculate as follows: WJ 100 Centre Spacers required: (On average you will require 1.4 spacers/pod or 0.9 spacers/m2 of floor area)

• One (1), Centre spacer per internal pod,
• Plus, one and a half (1.5), Centre spacers for every pod around the edges,
• Plus, one (1), extra Centre spacer for each pod on an external corner. (Fig. 6)

WJ 101 Clip-on Spacers required: (For 300mm edge beams you will require on average 1 spacer/m of boxing)

• To increase the edge beam detail from 200mm to 300mm you will require a WJ 101 Clip-on spacer for every Centre spacer where the edge beam needs to be wider. Each Clip-on spacer will increase the beam width an additional 100mm. (Fig. 5)
• The same calculation is required when increasing the width of internal ribs. (Fig 7)
• Plus, on external corners, two extra Clip-on spacers will be required for 300mm edge beams. (Fig. 6)

Notes:1) In some cases it will be easier to join two WJ 100 Centre spacers together rather than using several Clip-on spacers. (Fig. 8)

300mm edge beam Fig 5.

300mm external corner Fig 6.

200mm internal beam Fig 7.

400mm internal beam Fig 8.

How to order?

Contact Polyreform Ltd

• Helen Mays (Director) 027 22 44 154
• Quentin Townsend (Sales Manager) 021 0264 5709
• Graeme Blackley 027 446 5401 (Palmerston North)
• Tui Lewis 027 573 5078 (Hastings)