Builders and Suppliers of Wide Span Curved Roofs

Tenders & Current Projects
Header Image

Spantech Defence Buildings

Explosive Ordnance Storage and Other Blast Resistant Earth-Covered Buildings

Spantech has designed and tested a range of hardened earth-covered buildings (ECB’s) specifically for Defence applications.

The inherent arch shape and unique advantages of the Spantech Construction System are ideally suited for the construction of building which are hardened with reinforced concrete and covered with earth.  They are incredibly strong, fast to construct and cost effective.

The Spantech arch is light weight, yet very effective at resisting the blast impacts.

Most of Spantech’s hardened buildings can be modified to be protected from specific weapons or threats, or resist and protect their contents from specified explosive blast pressures.

Spantech’s construction technology has been applied to a wide range of Defence buildings.

Spantech Explosive Storehouses

Spantech’s most popular Defence building is the Spantech Explosives Storehouse (ESH).  The Spantech ESH is a 7 Bar earth-covered Type 4 Igloos which can be licenced to store up to 75,000kgs (NEQ) (165,000lbs) of HD1.1 at minimal (D3 and D4) NATO separation distances.

Spantech has three standard designs.  All feature a Spantech 300 Series panel lining an earth-covered concrete structure:

  • Spantech 13m ESH
  • Spantech 23m ESH and
  • Spantech 17.5m ESH

The numerator in the name describes the nominal internal width of the building.

The 13 and 23m feature an internal arch rising from floor level. The arch is a continuous segment of a circle.

The Spantech 17.5m ESH features a light-weight arched roof supported on vertical side and end walls.

Each ESH is designed to suit different storage requirements: different numbers of pallets, different types of munitions and ordnance and various siting requirements of the EO facility.

In their standard configuration the Spantech ESH can store:

Standard Length Standard Pallet Capacity* Max. Extended length Extended Length Pallet Capacity
Spantech 13m ESH  13 m 96 25 m  Available on request
Spantech 23m ESH  15.6 m  220 25 m  Available on request
Spantech 17m ESH  TBA  360  TBA  Available on request

* Based on 1200 x 1200 x 1200 pallet in layouts meeting NATO requirements

Design Options

All current ESH designs can be constructed in a range of lengths from 13m to 25m long to suit individual requirements.

Spantech has the design experience and qualifications to modify most elements of the design to suit ancustomer’s individual requirements.  For example, Spantech offers a range of options in the the following key areas:

  • blast door sizes and number of doors
  • blast door operating systems (manual, mechanical or electric, or a combination of these)
  • the number and location of personnel doors
  • blast valves
  • ventilation systems (passive and/or mechanical ventilation)
  • air conditioning and/or dehumidification systems
  • floor heights, slopes and floor finishes
  • linemarking options
  • standard pallet racking or bespoke racking for over-sized ordnance
  • erosion prevention or minimisation systems
  • lightning arresting and earthing systems
  • roof access and fall prevention systems and
  • electrical layout options and
  • security system options.

See recent Explosive Storehouse projects.

Tested in Full-Scale Explosive Trials

The design and structures have been exhaustively tested in a series of full scale explosive trials.

Spantech ESH proven in full scale trials

Spantech Explosives Storehouses have been subjected to seventy-five thousand kilogram (75,000kgs) (NEQ) HD1.1 blasts at minimal NATO separation distances.

A comprehensive series of full scale donor and receptor trials were conducted in 1991 and 1992 at the Woomera testing range in South Australia.


The aim of the trials was to determine the ability of the cost effective Spantech designs to provide satisfactory protection for their contents and prevent propagation to adjacent storehouses in the event of an accidental explosion occurring within the NATO inter magazine safety distances.

The trials were conducted by the Australian Department of Defence in conjunction with the United Kingdom Ministry of Defence and a division of the United States Army Corps of Engineers.

The Spantech ESH is now the benchmark for ESH projects undertaken by the Australian Department of Defence, Ministry of Defence, New Zealand and many others.

Test Overview

The key stages of the tests were:

Stage I
Three Spantech 13m ESH [receptors] were constructed at D3 and D4 distances from a UK Double Bay Igloo donor.

The donor contained 75,000kgs (NEQ) of HD 1.1 and was wired at 600 points for instantaneous detonation.

All three Spantech 13m ESH receptor buildings survived.

Stage II
Three Spantech 13m ESH [receptors] were subjected to an open air blast with 75,000kgs (NEQ) of HD 1.1 placed on an adjacent concrete slab.  The stack was again wired at 600 points for instantaneous detonation.

All Spantech 13m ESH receptors survived.

Stage III
A Spantech 13m ESH [donor] was filled with 75,000kgs (NEQ) of HD 1.1 wired at 600 points for instantaneous detonation.

A new Spantech 23m ESH [receptor] was constructed for Stage III. The design included an internal double arch stepped to allow additional pallet storage in the rear wall.

All receptors survived.

Stage IV
A Spantech 13m ESH (donor) was subjected to a series of HD 1.2 burns. The largest burn featured over five thousand 105mm shells in a stack comprising 160 pallets.

The donor building suppressed the series of explosions and all Spantech buildings survived.


The Australian Ordnance Council advised, “the Spantech 13m and 23m Spantech Explosives Storehouse designs are acceptable for use and qualified for use as Bar 7 igloos.”

In particular:

  • During all stages of testing the Spantech ESH survived the force of the blast and proved to be able to satisfactorily protect the contents to a serviceable standard.
  • The fragmentation spread of the Spantech ESH was significantly lower than comparable structures, with the fragmentation spread remaining within the recommended NATO safety guidelines.

International Acceptance

Since the successful testing, the Spantech 13m ESH and/or Spantech 23m ESH are now specified and widely used by Defence Departments in Australia, New Zealand,the United Arab Emirates and Malaysia.

For more information download the Spantech Defence brochure.

A Full Range of Defence Buildings

Today Spantech’s range of Defence buildings for a wide range of defence applications, including the following key areas:

  • ExplosivesExplosives Ordnance Storage, Ammunition Preparation Buildings and EO Loading Facilities;
  • Aircraft – hardened aricraft shelters, rapid deployment shelters with aircrew accommodation, bomb loading facilities, and non-hardened shade structures and aircraft hangars for fighter aircraft and training aircraft;
  • Essential Services – for the protection of critical infrastructure, plant and equipment;
  • Personnel Protection – for the protection of front-line aircrew, rapid deployment facilites, underground command centres and VIP survival facilities with decoy buildings;
  • General base buildings – All other types of conventional buildings for general base operations:
    • gymnasiums and aquatic centres;
    • mess and barracks;
    • office buildings, training centres and special-purpose training facilities (such as indoor target range);
    • warehouses; and
    • shade structures for personnel and equipment.

Remote Construction

The Spantech construction method is ideally suited to remote or isolated locations.  To date the company has successfully completed projects right across Australia from Woomera to Weipa, in New Zealand, Malaysia, Saudi Arabia and the United Arab Emirates.

See some of Spantech’s remote Defence projects