Alpha Construction Ltd

01283 733688

info@alphaconstruction.co.uk

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Wymondley

Construction of a GIS building & transformer infrastructure within a live substation

Client : Burns & McDonnell

End User : National Grid

Location : Hertfordshire

Contract Value : £2.2m

Project complexities, simplified by Alpha:

  1. Delivering works within and adjacent to a live high-voltage substation, requiring strict safety controls, sequencing and segregation to maintain operational integrity and protect personnel.
  2. Managing proximity to live equipment, overhead lines and existing pylons, requiring detailed planning and safe systems of work to mitigate risk.
  3. Coordinating works across both live and external areas, ensuring efficient delivery while maintaining clear separation between construction and operational activities.
  4. Working around existing drainage outfalls and manhole chambers, requiring careful integration and adaptation of infrastructure without disrupting existing systems.

Scope of Works:

  • Enabling works including vegetation clearance, topsoil strip and site preparation, forming the platform for new infrastructure outside the existing substation compound.
  • Installation of CDM and palisade fencing, ensuring safe segregation and site security throughout construction.
  • Diversion of existing drainage systems and removal of redundant cables, enabling integration of new infrastructure without disrupting existing services.
  • Construction of stone platform and reinforced concrete raft foundation, providing a stable base for the GIS building.
  • Erection of steel portal frame and cladding system, forming the building envelope for critical electrical infrastructure.
  • Installation of ducting, access roads and security doors, supporting operational requirements and future maintenance access.
  • Internal fit-out works, including raised access flooring and internal finishes to accommodate GIS equipment.
  • Construction of SGT1 transformer bund, earthing transformer bases and equipment foundations within the live substation, including excavation, RC construction, earthing installation, ducting and backfilling.

Ready to Build with Confidence?

Let’s shape a smarter, safer, more efficient solution, together.

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Alpha Construction Ltd

Why Alpha Construction Ltd?

We support clients from the earliest stages of a project to help shape practical, buildable solutions before work starts on site.

Adding Value Early

Adding Value Early

Early Contractor Involvement allows us to contribute our delivery experience during the design and planning stages, helping test options against real site conditions and reduce the risk of later change

Trusted Delivery Teams

Trusted Delivery Teams

Our directly employed teams provide continuity, accountability and practical site experience throughout delivery, supporting consistent standards of safety, quality and programme management.

Proven in High-Risk Environments

We regularly deliver projects in live, complex and highly regulated environments where safety, planning and coordination are critical. This experience allows us to manage risk effectively and maintain control of programme and quality, even when conditions are challenging.

Framework & Public Sector Ready

Our processes and reporting are aligned with framework and public sector requirements, supporting strong governance, transparency and compliant delivery throughout the life of a project.

Transparent, Competitive Pricing

Transparent, Competitive Pricing

We provide clear, considered pricing supported by open communication around scope, risk and delivery requirements. This helps clients make informed decisions and maintain greater visibility over costs throughout the project.

Relationship-Driven Delivery

Relationship-Driven Delivery

We work collaboratively with clients, designers and stakeholders to build long-term working relationships based on trust, communication and consistent delivery. This results in smoother projects, quicker resolution of issues, and stronger outcomes over time.

Ready to Build with Confidence?

Let’s shape a smarter, safer, more efficient solution, together.