ÍSTAK’s history begins in fact with the masonry company E. Pihl & Søn that the engineer Kay Langvad bought in 1947. Kay was an independent entrepreneur in Denmark who was married to an Icelandic woman, Selma Gudjohnsen. E. Phil & Søn undertook various types of construction projects including harbor building in Denmark and water power plants in Iceland. The company grew and flourished over the next two decades and bythen Soren, the son of Kay and Selma, had become more active in the company. The Búrfell’s plant was the first large hydroelectric power plant in Iceland and E. Phil & Søn handled the construction of it along with a Swedish company and the Iceland construction company Almenna bygginarfélagið. The Búrfell’s plant project was mostly completed in the year 1970.

After the construction of the Búrfell’s plant Langvad and his son along with four Icelanders founded the company Íslenskt verktak sf. On November 18th 1970 the company was converted into a corporation and given the name ÍSTAK. Later the name of Íslenskt verktak sf was also officially changed into ÍSTAK Ltd.

ÍSTAK’s first projects were construction of the sea Þórisvatn, the water power plant Vatnsfellsveit and enlargement of the Búrfell’s plant. Many projects followed such as: The National Ring Road, tunnel under the fjord Hvalfjörður, the factory Norðurál in Grundartangi, various subterranean tunnel, flyovers in Mjódd in Reykjavík, the house for the printer Morgunblaðið, the harbor Skarfabakki in Sundahöfn, the aluminium plant Helguvík and Álverið, the airport in Keflavík, IKEA in Garðabær, the City Hall and so on .

Construction at its finest is ÍSTAK’s motto, which also indicates the thorough knowledge of techniques and working methods needed to diversify ÍSTAK’s constructions and projects. ÍSTAK’s goal is to meet the needs of Icelandic and foreign customers in buildings, and other constructions projects and provide customers with the best available service.

ÍSTAK has always focused on having technicians and experienced supervisors in implementation of projects that the company undertakes, ensuring the quality and the buyer’s satisfaction.

In 2015 the Danish contractor Per Aarsleff AS acquired 100% of ÍSTAK. With this acquisition came a very strong basis for continued operation of ÍSTAK and insurance that ÍSTAK remains a leading contractor in Iceland.