The boards on Dunedin’s many, many wooden houses don’t last forever. So when it’s time to replace, there are a few tricks that can make the job go more smoothly, writes Peter Dowden.
Dunedin and Otago have plenty of weatherboard buildings, often made from the forest that was cleared to make room for more settlements. They can be draughty and cold, and a classic complaint here in the South is that the wallpaper billows inwards during a gust of wind. So you’ve relined all the rooms, putting insulation in the external walls as you go ... Then the weatherboards, already on the shabby side, start rotting in earnest.
The void inside the walls was probably keeping your old boards sound and rot-free with constant ventilation until you stuffed it up by insulating. So follow the practice of most modern builders and you will find the job easier and probably get several extra years out of your house’s next round of cladding.
The essential extra is battens of the cheapest rough-sawn treated pine normally used to edge lawns and flowerbeds. 50x25 strips (two-by-one in the old style) are nailed to your studs over the building paper and this gives a waterproofed breathing space behind your boards that will keep them dry and rot free for years to come.
Old framing in your house can be hard as steel in some places and a trifle soft in others, so a bonus of these new battens is they provide a stable new surface to attach your weatherboards.
At the bottom of the cavity there needs to be room to allow air in and moisture out; the professionals add a mesh mouse barrier here sized to match the battens.
Before you start: Make sure your house is worth re-cladding (it might have failing foundations or so much rot that it is big orange digger time). Get good advice from hardware suppliers and your local council about materials and how much of this you are allowed to do yourself.
