Bulk Bags & Rubble Sacks

Bulk bags, and the lifting question

An 850mm bulk bag holds around a tonne of aggregate, which puts it firmly into lifting operations territory the moment a machine picks it up.

Two things decide whether that lift is safe. The bag must be rated for the load and in sound condition, and the lifting loops must be intact and correctly engaged on the hooks. A bag that has been out in the sun for a season is not the bag it was when it arrived: polypropylene degrades under UV, and the loops fail before the body does.

Understand whether a bag is single trip or designed for reuse. Single trip bags are exactly that, and reusing one for a second tonne is how a load lands on somebody. Nobody stands under or near a suspended bag, whatever the rating says.

Rubble sacks

Heavy duty rubble sacks take the sharp, heavy waste that splits an ordinary refuse sack: broken tile, plaster, brick ends, cut-offs.

The gauge is what you are paying for. A thin sack costs less and bursts when it is lifted, usually at the top of a stairwell, and clearing that up costs more than a box of proper sacks.

Packs of 10 suit a van and a single job; rolls suit a site with a steady flow of waste. Fill to a weight one person can lift rather than to the top: a full rubble sack is heavier than it looks and manual handling injuries from carrying waste are a recurring cause of lost time.

Sandbags: hessian or polypropylene

Both are here and they behave very differently over time.

Polypropylene is stronger, does not rot and handles wet conditions, which makes it the choice for flood defence and general site use. It degrades under prolonged sunlight, so a wall left in place for a season starts failing.

Hessian is natural fibre. It grips and beds down against its neighbours better than woven plastic, and it biodegrades, which is an advantage where bags cannot be retrieved and a disadvantage where they need to last.

For a wall that must stand for months, polypropylene under cover. For short term and for anywhere the bags will be left, hessian. Hessian rolls also serve as frost protection over fresh concrete and as general covering material.

Rubbish chutes

Scaffold chutes take waste down from height without anybody carrying it down a ladder or dropping it over an edge.

They come in 20", 22" and 30" diameters, and larger is not automatically better: the diameter needs to suit the material so it falls freely rather than jamming halfway. Chutes are modular, so the run is built to the height, and the bottom section needs to discharge into a skip with the area below barriered off.

Dust is the part that gets underestimated. A chute discharging into an open skip in a public area produces a cloud every time something goes down it, which is why the discharge point gets damped down and screened.

For containers and mixing tubs, see bins, buckets and tubs.