Henrik Johan Henriksen and Waldemar Kähler decide to establish a gravel pit called ‘Singelsforretningen Omø'.
1914
The company changes its name to:
‘Korsør Stenforretning'.
The breakthrough in the production of aircrete comes with the research by Alysworth and Dyer, who expand calcareous mortar with metal powder (aluminium powder) and patent their invention in 1914.
1918
Valdemar Kähler dies. The business affairs are taken over by his son (Gustav Kähler).
1919
Acquisition of the ‘Ølsted Kalksandstensfabrik' gravel pit.
This factory is later adapted to the manufacture of Celcon aircrete.
Acquisition of the ‘Nymølle Skærvefabrik' factory in Denmark and specialisation of the plant in the sale of calcium-silicate brick and gravel.
Swedish architect A. Eriksson combines the cell formation process and steam curing, thus creating the first modern aircrete. He obtains a patent for his invention.
1927
The acquisition of ‘Hasle Klinker Chamotstenforretning'.
1929
Start of mass manufacture of aircrete products in Sweden.
At the beginning of the 1930s the company has to build additional plants to keep up with the demand for aircrete products.
1933
Henrik Johan Henriksen dies.
His son takes over the business affairs (Finn Henriksen).
1934
The company again changes its name to ‘Henriksen og Kähler'.
1937
Research to enable production of aircrete in Denmark.
1945
A method of cutting with tautly strung steel wires developed in Germany. The result – very accurate dimensions. The cutting of raw concrete guarantees reuse of the remains, so the manufacturing process is waste-free.
1949
Celcon Ltd. The company reaches the level where it can manufacture aircrete.
1950
Permission granted to build the first autoclave, required for the manufacture of aircrete blocks.
1953
Start of aircrete manufacture in Poland (Faelbet Warsaw).
Erection of Celcon Ltd. plant in Grays, Essex (cooperation agreement between Celcon Ltd., Christiani & Nielson, and ‘H og K').
1959
The 50th anniversary of the ‘H og K' company.
1961
In Poland the Prevar plant in Skawin and Prefabet in Lidzbark start to produce aircrete.
1962
Henriksen and Kähler separate their activities. The company splits in two:
- an aircrete manufacturer, named ‘Henriksen og Henriksen A/S'
- a mineral wool manufacturer, named ‘Rockwool Ltd'.
Since then both companies have been run independently.
1963
End of cooperation between ‘Christiani & Nilson' and ‘H og H'.
1966
‘Celcon Ltd' and ‘H og H' build a new plant in Rugeley, Staffordshire.
1971
Construction of a new aircrete plant in Gadbjerg.
1978
Erection of a new plant in Pollington.
1985
The H+H shares are admitted for official quotation on the Copenhagen Stock Exchange.
1988
Acquisition of ‘B-Gruppen' (producer of Expana lightweight concrete with gravelite).
1990
Change of the Group structure. Establishment of H+H International A/S.
1991
Establishment of H+H Industrie GmbH
(H+H Expan GmbH).
1996
Organisation of an Expan manufacturing plant in Ølstedt.
1998
Acquisition of minority shareholding in Kingsway Croup plc.
1999
Division of H+H Industri A/S (presently H+H Celcon A/S) and establishment of H+H Expan A/S.
Acquisition of the Norwegian company Scanpor A/S (presently H+H Celcon A/S).
Acquisition of the Finnish company Suomen Siporex OY (presently H+H Siporex OY).
2000
Establishment of the Swedish branch of H+H Celcon AB.
Merger of H+H Expan A/S and Fiboment A/S.
Expansion of the plant in Pollington, England.
H+H acquires Hebel Wittenborn and Ytong Ham Uentrop.
2005
H+H expands production in Wittenborn. From spring 2006 the company will produce special construction materials to supplement the product line. Acquisition of five production plants in Poland with the production capacity of 1.1 million m³.
FAELBET Warsaw (the first Polish mass producer of ‘siporex' aircrete)
PREFABET Puławy
GOFABET Gorzkowice
PREFABET Lidzbark
PREVAR Skawina
2006
Acquisition of an aircrete manufacturing plant in the Czech Republic.
H+H established sales companies in Ukraine and Slovakia.