Viikki Church, built in 2005 and designed by architect Samuli Miettinen, represents modern Finnish wood architecture. The church has a large wooden floor which has unusual characteristics. Very few large wood floors have been built with the combination of under-floor heating together with a reinforced concrete foundation. Therefore it is not known how the floorboards will behave when subjected to the combination of under-floor heating and natural humidity variation occurring over the year. The floor is made of feathered spruce floor boards (30 mm x 120 mm) sawn between the tangential and radial directions. The floor was treated with a mixture of lye and oil.
This poster presents the methods used in a study about the moisture behavior of the wooden church floor. The study presented is a follow-up to an original study carried out between 2005 and 2006, right after the completion of the church. The aim of the original study was to observe the moisture behavior of the wooden church floor over a period of one year. The follow-up study repeats the same measurements. The aim is to observe the behavior of the floor after it has been in service for 5 years. Of particular importance are the gaps between the floorboards; if they are wide enough to allow moisture movement. Also the moisture content is recorded at different points in the church building.
The humidity of the church hall floor boards were measured with a capacitive humidity meter. Floor deformation, cracks and widths of the floor edges were measured with a measuring tape. The indoor air relative humidity and temperature were recorded constantly. The results of the original study showed that the variation in moisture content was between 6 and 12 %. The gaps between the floorboards were 1.5 to 3.5 mm wide during the dry winter period. Also some recommendations about the maintenance of the floor could be made. The follow-up study is ongoing research, the results will show if the floor behaves differently after five years in service.
Keywords: wood, flooring, moisture behaviour, Viikki church
Authors
Silvo J.
School of Chemical Technology, Aalto University, Aalto, Finland
Koponen S.
UPM-Kymmene Wood Oy, Lahti, Finland
Paajanen O.
School of Chemical Technology, Aalto University, Aalto, Finland
Vahtikari K.
School of Chemical Technology, Aalto University, Aalto, Finland
Kairi M.
School of Chemical Technology, Aalto University, Aalto, Finland
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