Party Like It's 1999 (2015 edition)

A Party wall is a main separating wall between buildings.  Responsibility for the wall is normally shared between the owners of the buildings (the parties).  In this case the Party wall is the wall which separates the two homes within this semi-detached building.

The last time i worked full-time as a joiner was 1999 and whilst the skills and techniques remain the same, the building regulations of 2015 have changed a wee bit.

The party wall was parged (coated in cement render) at the start of the year.

The building regulations require the construction of a 150mm x 50mm partition at the party wall.  This partition, like the oxter walls, will need to be insulated by the fitting of 145mm insulation batts and 40mm Kingspan/Celotex insulation board.  In the case of the party wall partition the 40mm insulation board is to be fitted on the back side of the partition and i've left space in the partition (the missing dwangs) for this to be slid into place later in the project.  It saves a £50 delivery charge if i make one large order of insulation with free delivery rather than 1 small and 1 large order.

One of the other changes in building regulations is that a minimum gap of 25mm must be kept between the back edge of the finished partition and the party wall to ensure adequate ventilation within the loft space around the whole 'box' of the conversion.  In this case the back edge of the partition will be the insulation board and the bare timber partition had to be built 65mm away from the wall to account for the 40mm insulation board.

The Party wall partition requires to be finished with two sheets of 12.5mm plasterboard which are then to be fully plastered, so overall the finished partition will be approx.. 220mm broad.  Hopefully that should provide adequate thermal and acoustic insulation between my neighbours and I.