Weatherboard houses are lightweight constructions with timber framed walls and external weatherboard cladding, timber framed floors on stumps, timber windows and roof tiles. The timber walls will easily transfer heat and cold; cooling down quickly in winter and heating up quickly in summer.
Most weatherboard houses are unlikely to have insulated walls. Because the fabric of the weatherboard is less robust than brick, adding wall insulation is a must-do for the weatherboard renovator.
Assumed improvements to existing weatherboard style home with 180.3m2 floor area in Melbourne climate zone, 'always home' usage profile, Lee, T., Wu, C., Guthrie, K. and Dewsbury, M., 2014
Install bulk insulation into the walls when an extension is added or rotting timbers are replaced, as this is when the builder removes walls linings. Your builder or installer should ensure that the insulation product supplied is less than 90mm high so that the insulation is not compressed when installed. Your builder should also recommend a type of building paper, house wrap or reflective foil to separate the insulation from the weatherboard to avoid condensation.
Rotting timber and/or general wear and tear can create gaps between weatherboards in walls, floors and around doors and windows. Repairing and sealing these gaps – draught-proofing your home – is well worth the effort, as it will reduce heat loss in winter and heat gain in summer, saving you energy and money.
It is possible to retain the character of your weatherboard home when renovating, by retaining existing timber window frames for example. One option is secondary glazing, where lightweight acrylic panels sit 100mm off the original glass panes, adhered via magnetised frames.