Assembly of Steel Structures
About the service
We install prefabricated steel structures and technological equipment.
Design
Delivery
Installation
We build Estonia’s largest industrial buildings
From 100 meters up in the air to a kilometer beneath the surface, we handle installations in even the most demanding conditions. We have constructed mining conveyors extending up to 6 kilometers and erected steel frame structures weighing up to 7,000 tonnes.
- Profiled sheeting installation
- Prefabricated sandwich panel assembly
- Sheet metal trimming and cladding finishes
- Precast concrete element erection
- Installation of technological equipment
Our projects
Rakvere Football Hall
Industrial and production facilities
Rakvere Football Hall
The steel structures for the Rakvere Football Hall (also known as Bauroc Football Hall) were designed by Norte and Maru Metall, manufactured by Maru Metall, and installed by Maru THM. The football facility features a permanent playing field and measures 74.5 by 113 meters.
Steel Structures for VKG Uus-Kiviõli Mine Conveyor
Industrial and production facilities
Steel Structures for VKG Uus-Kiviõli Mine Conveyor
In September 2026, Viru Keemia Grupp (VKG) officially inaugurated the new Uus-Kiviõli mine, a project valued at EUR 75 million, featuring conveyor steel structures installed a year earlier by Maru THM.
The project scope involved installing the conveyor’s steel structures spanning nearly 6 kilometres from the Uus-Kiviõli mine to the existing Ojamaa mine, including a river crossing. In total, approximately 1,000 tonnes of structural steel were erected.
Steel Structures for Aircraft Engine Test Facility
Other
Steel Structures for Aircraft Engine Test Facility
Enefit 280-2 Chemical Plant: Retort Building and Substation/Control Building
Industrial and production facilities
Enefit 280-2 Chemical Plant: Retort Building and Substation/Control Building
The second shale oil plant for Enefit Power, located within the Auvere chemical industry complex, is a globally unique facility and represents Estonia’s largest single industrial development of the past decade. Enefit 280-2 comprises several buildings – the technological heart is housed in the retort building, with the equipment’s command center located right next door in the control building. In the adjacent turbine hall, electricity is generated using waste heat.
The retort building is the largest single structure among them, featuring a subterranean level extending up to 5 meters deep and a peak height of 72.4 meters.
Every room and level required close coordination during construction with the technology designer and supplier. The building was constructed in stages: following the main phases, major technological equipment was installed directly into its final position. Certain equipment components consisted of massive segments measuring nearly 10×20 meters, weighing over 100 tons, and requiring installation tolerances within millimeters. The building’s fire safety engineering was equally complex.
Structural steelwork forms the load-bearing framework for both the building and the production technology, complete with hundreds of maintenance platforms and catwalks. In total, the building incorporates 132,947 steel structural elements, with installation taking over a year across two shifts.
The retort and turbine buildings utilize approximately 12,200 cubic meters of concrete structures in total, ranging from foundation slabs and equipment support frames to 10-meter-high walls and a 50-meter elevator and stair shaft.
NPM Narva Magnet Factory
Industrial and production facilities
NPM Narva Magnet Factory
Nearly the entire Maru Group was involved in the construction of the production facility for rare earth magnets of Canadian manufacturer Neo Performance Materials (NPM), which opened in Narva in 2025. The news of the 100-million euro investment making its grand opening garnered worldwide attention and made headlines in publications such as the Financial Times and the New York Times.
NPM proudly emphasised that the plant was completed “on time, on budget and on spec”. Owing to a trust-based partnership with the client, the design and construction work was based on a tight but realistic schedule drawn up by Maru. The plant was completed in just 500 days, a fact that was commented in the media by NPM executives that in the United States, for example, this process would have taken four or five times as long.
Elcogen’s Office and Production Facility
Industrial and production facilities
Elcogen’s Office and Production Facility
Paide Football Hall
Sports and leisure facilities
Paide Football Hall
The football hall features a full-size artificial turf pitch alongside two tartan running lanes. The new facility serves as a training ground for youth players, schools, and kindergartens, as well as the home venue for Paide town’s flagship team.
The building features a 77-meter clear span and an axis-to-axis length of 113 meters, maintaining a comfortable indoor temperature of 15°C. Designed for versatility, the hall can host various competitions and events – even dance festival rehearsals – and is equipped with high-quality broadcast lighting for TV transmissions.
Hanhikivi-1 Nuclear Power Plant Reinforcement Shop
Energy infrastructure
Hanhikivi-1 Nuclear Power Plant Reinforcement Shop
Naantali Boiler House
Energy infrastructure
Naantali Boiler House
In-building expansion work at the Telia Data Center
Office buildings
In-building expansion work at the Telia Data Center
Hanhikivi 91USV Laboratory Building
Industrial and production facilities
Hanhikivi 91USV Laboratory Building
Installation of Steel Structures at Outokumpu Kemi Mine
Industrial and production facilities
Installation of Steel Structures at Outokumpu Kemi Mine
At your service
Maru THM OÜ
Our experienced installation team brings extensive experience in executing large-scale projects.