House B: A single-leaf wall house built from the early 1950s onwards.
Distribution: Very common in Dublin in Lucan, Raheny, Dundrum
Upgrade: External insulation, ‘cold’ roof, partial airtightness upgrade

 

house a

 

 

1) In this case the decision has been made to use external wall insulation. This avoids having to lose room area, re-decorate internally, lose period details such as the plaster cornice shown. It may also reduce the time the family has to move out for. Any proprietary external wall insulation system will make the wall more wind tight and drier and as a result less conductive. Most external wall insulants can be used on top of relatively smooth napp finish renders, but not on top of pebbledash. An exception in this regard is ‘Brillux’ from Greenspan. The latter uses expanded polystyrene insulation. We also specify woodfibre-based external wall insulation systems as they deal well with moisture and use less energy and oil-based products. Examples include ‘Diffutherm’ and ‘Gutex’, from NBT (agents Econstruction and Lochplace) and from Ecological Building Systems respectively. Note that in the case of this house we have taken the external wall insulation (without its final render coat) right over the top of the external wall to ensure a total insulation ‘wrap’.

 

 

5) Quilt insulation should be fitted tightly between the ceiling joists and then laid tight together (in the opposite direction) over the joists. The insulation could be mineral wool, hemp wool or sheep’s wool. Note that natural insulants can absorb and release greater quantities of water vapour without collapsing. If the homeowner can’t budget for a full airtight installation (as shown in House C) we would recommend using natural quilt insulants. Remember that unless you create a raised platform that prevents crushing of the insulation this attic cannot be used for storage. Crushed or collapsed insulation has little or no thermal value.