The internals are now starting to transform the space from being a building site. The extension area at both the lower ground level and ground level is now being boarded out. The ceiling boarding is magnesium silicate by Multi-Pro. This is a moisture resistant board and has a greater breath-ability than plasterboard. The external walls will be plastered, but we have used 62.5mm Kingspan K17 insulated plasterboard on the internal walls (external prior to extension) that have been underpinned.
The floor insulation has also been laid. Again, we have used Kingspan K3 floorboard. This is 100mm thick, and achieves a U-value of 0.13 W/m².K. The insulation is laid directly onto the sub slab and covered with polythene ready for the screed. The screed arrived today on a mixer lorry. We are using a liquid flow screed, which allows a thinner layer (30mm) compared to traditional sand/cement screed (65mm). I’ve not used this type before, so will be interested to see how successful it is.