Groundworks Jargon Explained

Confused by groundworks jargon? Here are some explanations of the different terminology you might come across:

Backdrop

Where underground drains run, they must go lower but it is not always possible to increase the downward slope exceeding certain limits as anything other than a clear liquid would be left. The way to solve this is to build a hole where it came at the top and impurities are then free-falling vertical pipe in the hole to a new lower level. The advantage of this method is that the hole is easily accessible for rodding out any blockages. This hole is called a backdrop.

Benching

Channels in the bottom of the hole are finished with smoothing mortar made to form a cleaner slope. This is called the benching. Sometimes benching will rupture causing it to block.

Bit-mac

Bitumen Macadam is a coated aggregate, which is put down hot onto a road surface and driveway. It is normally placed as two basic layers with a base layer and a coarse layer. Solid bitmac is the name given to a graded rock where smooth stones mix in to complete the gaps and add power. It is often used for heavily traffic roads or driveways.

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Blinding

This is a sand topping around 30-50mm placed on the surface of the sub-base to prevent the topping from running into the sub-base. The blinding also allows the topping to move independently of the sub-base. When you need help with a groundworks project, consider Groundwork companies Bristol at a site like Chew Valley Construction, a top name in Facilities management companies Bristol.

Brushed Concrete

The concrete surface is smoothed and then finished with a soft broom dragged across it to provide grip.

Damp proof membrane

Damp proof membrane is placed directly under the concrete floor slabs of concrete to avoid issues with rising damp. It is also often used over blinding to provide a non-slip membrane to ensure there is no binding between the layers.

Formation

Deepest point in an excavation for a drive or a terrace, which is flattened and smoothed before laying the sub-base.

Hepsleve

A trade name for very tough clay pipes that are connected with a plastic collar.

Plastic

Plastic pipes are often used in underground drainage in the country, as they are lighter and longer than clay pipes. The disadvantage is that the pipes are not as strong and may have to be encased in concrete under certain conditions, negating any flexible quality. In such circumstances, clay may be a better option.

Salt-glazing

Before the current pipes of today were used, pipes used to be made from baked clay. The clay pipes used to be covered with a clear glaze that was kiln-fired to guarantee a smooth impermeable surface. These pipes were jointed with sand / cement and tarred hemp.

Spoil

Material excavated from the excavation site, which can be referred to as muck is removed from the site.

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Sub-Base

The coarse fills such as hardcore or crushed stone form a strong frost-resistant base and cushions to spread the load. It is usually at least 100mm thick.

Tamped concrete

Compacting concrete surface with long heavy boards leaves shallow ridges behind. shallow mountain. These ridges should be shallow to allow the water to drain.