Final answer:
Rigid insulation in a cavity wall is typically installed in a vertical placement to align with the studs and should be sealed properly to prevent air leakage, following the manufacturer's instructions and local building codes.
Step-by-step explanation:
To properly install rigid insulation in a cavity wall, you should typically place the insulation boards in a vertical placement. This method aligns with the vertical studs and helps maintain structural integrity while also making it easier to cut and fit the insulation boards around any obstacles such as windows, doors, and electrical outlets. When installing, ensure that the insulation is cut snugly to fit the space without gaps. After placing the insulation, use appropriate tapes or adhesives to seal the joints and edges to prevent air leakage, which is crucial for maximizing the insulation's effectiveness. Correct installation will affect the building's thermal performance, energy efficiency, and comfort levels. It is also important to follow the manufacturer's instructions and local building codes during installation. Insulation should not be compressed, as this will reduce its insulative properties. If any electrical wiring or plumbing is present within the cavity, the insulation should be carefully installed around these components without causing damage or creating fire hazards.