Quick Answer
Yes — 50-80mm insulated plasterboard (PIR, phenolic, or graphite EPS) brings solid 9-inch brick walls from ~2.1 W/m²K down to 0.30 W/m²K, meeting Part L retrofit targets for Maidstone's Victorian terraces.
Yes. Insulated plasterboard adds thermal insulation to external walls. For the uninsulated solid 9-inch brick walls typical of Maidstone's Victorian terraces (Maidstone central, Bearsted and Loose), a 50-80mm insulated plasterboard (PIR or phenolic) can reduce U-values from around 2.1 W/m²K to 0.30 W/m²K, meeting current Part L retrofit targets.
Three common insulation options for Maidstone properties:
- PIR (polyisocyanurate): best thermal performance per mm, ~0.022 W/mK, thinnest build-up
- Phenolic foam: marginally better than PIR, ~0.018-0.020 W/mK, more expensive
- Graphite EPS: cheaper, ~0.030 W/mK, slightly thicker board required
We typically recommend PIR for Maidstone retrofit work because the thinner build-up minimises room loss, particularly important in small terraced kitchens and bathrooms.
Need a quote for this in Maidstone?
Send a brief, your plans or just a few photos. We will turn around a fixed-price quote within 48 hours, anywhere across ME14–ME20, TN12 and TN27 postcodes.