Building sealants: Ability to accomodate movements (NT BUILD 147)

Abstract

 

SCOPE

This NORDTEST method describes a testing procedure for determining the ability to accomodate movements of various types of building sealants.  

FIELD OF APPLICATION

Building sealants have to maintain their properties – i.e., to seal – for a sufficiently long period of time. In practice, the materials are subjected to certain deformation due to changes in temperature, moisture content etc. To be able to fulfil their functions, the materials must be able to accomodate these movements, and also to permit a sufficiently good adhesion to the substrate, even in aged condition. One single extension, as in NT BUILD 004, to test elongation properties will give some indication. This has, however, to be supplemented with a durability test where the sealant is subjected to a high number of cyclic deformations at simultaneous aging. This method can be used for all types of sealants in the groups 53 through 58, (Table 1, p 3), but not for putties or glazing compounds, groups 51 and 52 in the NBI general classification of jointing materials.