Thermal bridge free construction – step 2
Minimising thermal bridging is an issue for both designers and constructors and can result in very simple details for certain methods of construction: for example an insulated raft foundation combined with an externally insulated solid masonry wall provides a very simple floor-wall junction.
Other details will be inherently more complex, for example the installations of weather tight and thermally bridge free roof lights (which may be best avoided in Passivhaus building for this very reason). Implementation of thermal bridge free details requires forward planning and the availability of the correct materials at the right time during the construction process. If for example a single course of aircrete block work is required at the base of a wall constructed from aggregate blocks, the materials must be on hand to be incorporated at the appropriate time.
The design must be implemented according to the designers drawings, so the addition of timber studs or noggins where none are shown on drawings is not acceptable when constructing Passivhaus buildings as it will result in additional thermal bridging.
Read about steps one, two, three, four and five in our next articles.
Excerpt from “Passivhaus primer: Contractor’s guide. So you’ve been asked to build a Passivhaus?” by BRE.