Hillhouse opens £5m asphalt plant in Midlothian

Hillhouse Group has opened its £5m Edinburgh Asphalt production facility at Soutra Mains Quarry in Midlothian, extending its asphalt manufacturing network into the east of Scotland. Production began in October, with the new plant intended to serve contractors, councils and infrastructure projects across Edinburgh, the Lothians, the Scottish Borders and surrounding districts.

Soutra Mains already supplies aggregates, ready mixed concrete and concrete blocks, and the addition of asphalt manufacturing broadens the construction materials produced at the quarry. Hillhouse’s established asphalt sites are at Troon, Glasgow and Alloa. The group says the Midlothian facility is its first asphalt production operation in eastern Scotland during its 119-year history, rather than a transfer of capacity from another local site.

The production line is based on an Ammann ABA UniBatch 210 installation. Hillhouse specifies working capacity of 160 to 180 tonnes per hour, a 3.3-tonne mixer and two 50-tonne hot mixed-material storage bins. The plant has been designed for a minimum mixed product of one tonne, alongside a direct loading chute for smaller collections and hot boxes. Those figures describe the plant’s stated capability, rather than the tonnage already delivered since its opening.

A batch plant creates asphalt by feeding selected aggregate fractions into a dryer, screening and weighing them, then mixing the heated material with bitumen and specified filler. The material proportions and temperatures have to be controlled to achieve the intended paving mixture. At Soutra Mains, the Ammann installation brings cold feed, drying, screening, mixing, hot storage and loadout into one process. Each project mixture will still require its own specification and quality assurance arrangements.

The installation also provides for controlled input of recycled material through a dedicated pre-feeder. The equipment can incorporate suitable reclaimed asphalt into a mix, subject to its condition, the approved recipe and relevant product requirements. Hillhouse has not published a recycled-content percentage for the facility’s initial production or quantified emissions savings attributable to that capability.

Two 50-tonne hot storage bins separate the mixing and vehicle loading stages, allowing finished material to be held before collection. A weighbridge beneath the loading position supports measured dispatch, while a direct chute serves hot boxes and smaller pickups. These arrangements give the operator scope to handle different order sizes without requiring every customer vehicle to arrive at the same point in a production cycle.

Smaller contractors have different collection requirements from operators resurfacing long sections of carriageway. Utility reinstatement, footway maintenance and local patching may need smaller volumes, a suitable collection point and a predictable loading process. The Soutra Mains design combines a one-tonne minimum with a small-load chute and on-site reinstatement consumables, while the main plant offers capacity for larger planned works. That mix of provision is a notable part of the investment.

Temperature and journey duration constrain asphalt logistics. Material has to remain workable long enough for paving and compaction, and the acceptable conditions vary with the mixture, weather and job specification. Producing it near Edinburgh may reduce some delivery distances compared with Hillhouse’s existing plants to the west, although no actual route comparison or measured carbon saving has been released.

The quarry setting also provides a potential logistical connection between locally produced aggregates and asphalt manufacture. Aggregates from Soutra Mains can be used where they meet the relevant product requirements, but the availability of nearby stone does not remove the need for mix design, testing or control of binder and other constituents. The company has positioned the integrated site as a way to coordinate material availability and production planning across different contractor needs.

The company identifies carriageway works, footways, cycle routes, local authority maintenance, housing infrastructure and utility reinstatement among the potential applications. These are intended markets, not a confirmed list of contracts awarded to the new plant. Hillhouse has not provided an initial order book, annual output forecast or separately audited commissioning performance figure for Edinburgh Asphalt.

Production started in October following construction and commissioning of the new line. The stated 160–180 tonnes per hour remains an operating capability under appropriate conditions, while daily throughput will depend on orders, mix changes, maintenance and dispatch arrangements. The combination of bulk production, stored finished material and one-tonne minimum orders is intended to serve both large surfacing programmes and smaller repair jobs across eastern Scotland.