What is Pumped Cavity Insulation?
Cavity wall insulation is a method of insulating existing masonry cavity walls by filling an empty cavity with blown or injected insulation. The insulants available for cavity fill are commonly blown mineral wool and polystyrene beads. Insulation systems should be approved by NSAI Agrément. Filling cavity walls is a cost effective method of reducing heat loss through this type of wall.
However, the cavity and the wallls must be in suitable condition to allow for the cavity to have insulation pumped. The contractor should carry out an assessment of the cavity and of the condition of the walls internally and externally to ensure this insulation method is suitable. The wall cavity whouls be at leasty 50mm wide or be a width in accordance with the requirements of the insulation material's ceryification. Get a full assessment from a number of bead installers to compare prices, U-values promised, guarantees and their NSAI Agrément certification.
Filling cavity walls may not achieve the level of insulation required and may need to be supplemented with internal or external insulation to achieve the desired U-value.