Targeted Repairs and Treatment vs Re-Cladding
In 2005, the Moisture Detection Company patented the Mdu Moisture Detection Probes which have been installed discretely through the skirting boards in thousands of NZ homes.
Once the probes are in all locations where there may be a weathertightness risk, you have detailed information on any wet framing, any decay and what, if any timber treatment was used.
From that position of knowledge, you can make an informed decision about what to do next; do nothing, do targeted repairs and treatment, or go on for the full re-clad.
Targeted repairs and treatment have these goals:
- Stop the leaks and modify defective details to manage or stop future leaks.
- Ensure that timber that may be affected by current or future leaks is protected by adequate treatment. If the timber is untreated then post-treat with RotStop.
- Remove and replace decayed timber if it is affecting the structural integrity of the house – or just treat it and leave it.
That way buildings can be saved, remain healthy and liveable and for a lot less anxiety and costs. The Building Act does not mandate that no decay is allowed in a building. It does not even mandate no leaks. What it does mandates is that leaks are not to progress to cause structural problems, which is limited to load bearing, bracing and maintaining secure claddings and linings. External walls are often over engineered, with safety margins of 50% or more. Leaving minor decay that has been treated in some walls has no effect on the structure and remains in full compliance with the Building Act.
Compare this to a re-clad where any timber within one metre of visibly stained wood is marked for replacement. This can mean expensive replacement even if the staining is due to the framing getting wet during construction and is still good, sound timber.