Engineered composite panel or structural insulated panel (SIP) – These systems are growing in popularity. Low-mass insulation materials are bonded to lightweight steel, plywood or oriented strand board (OSB) sheeting and usually achieve high levels of structural efficiency with high insulation levels. Cost ranges from medium to high, depending on the system.
Composite mass floors Common examples of composite mass floors are:
-lightweight frames topped with concrete
-lightweight systems with water filled inserts to provide thermal mass
-autoclaved aerated concrete (AAC) floor systems
-phase-change materials embedded in low-mass materials to produce lightweight flooring with high thermal storage capacity.
Wall systems High-mass walls Common high-mass wall systems are masonry and include brick, concrete block and precast concrete. Other popular systems include rammed earth and mud brick.
Traditional masonry systems generally have high embodied energy while rammed earth and mud brick have significantly less. Rammed earth uses varying levels of cement depending on earth type and therefore has higher embodied energy than mud brick.All high-mass wall systems must be insulated, and provide most thermal performance benefit when insulated externally and exposed internally.
Note A common misconception is that thick walls such as rammed earth or mud brick do not need insulation. External insulation is generally required in cold climates.
High-mass wall system options include:
Double brick – These have high thermal mass and high embodied energy. They require cavity insulation. They are low maintenance (if unpainted) and highly durable on stable soil types. At the end of their lifespan they can be reused if lime mortar (which cleans easily) has been used. Less ideal is the use of high-cement mortar, as the bricks after use can only be crushed and recycled as decorative gravel or road base. They are usually high cost.
