Air and weathertight construction joints are critical when ensuring durable and energy saving joints for any building, both old and new. A wide range of materials and techniques are employed in the construction of modern facades as well as traditional construction. Therefore elastic joint sealants must be able to accommodate movement between a variety of substrates as well as ensuring a permanent bond. Effective thermal insulation and air-tightness afforded by high performance façade joint sealants are critical aspects to be considered as part of the total building energy consumption.