What’s Treatment got to do with it?

Building Industry Experience Shows

	We all know untreated timber rots.  So, why on earth do we build houses with it?
	It is the timber that needs to be durable – not the building code – the code can be re-written and changed – the timber can’t be removed from the building.
	All houses leak – somewhere, sometime, someplace despite all of our best efforts.  The framing gets wet during construction and is supposed to dry before the linings go on.  Unfortunately once the cladding and gib go on in many cases its too late.

What is needed? 

Maximum treatment affordable.  The cost benefit analysis shows treatment may cost $1,200 - $1,500 per house.  This is expected to drop to $400 - $600 when suppliers have competition.  That is only $8 - $30 per year as an insurance.  The average repair cost is estimated at $30,000.  That is for the first repair.  Then the rest of the walls rot and the owner has 2 or 3 repairs.  This becomes very expensive.

What should be treated?

Treatment must extend to all materials in the wall – gib board as well.

We guard against leaks but they still happen.  With treated materials the building can defend itself for a longer period of time – hopefully long enough to find the leak, pay someone to fix it, and allow the wall to dry out. With treated timber (and treating the other materials in the wall) damage will be minimal, simply call your builder, not your lawyer.  Do not get involved in the argument over what walls to treat and those not to treat.  Leaks radiate into buildings in a triangular fashion with the base of the triangle being the bottom plate of the wall.  The leak will not distinguish between internal and external walls – it will simply wet both.

Plumbing pipes and showers, (or dishwashers and taps) will leak at some stage in their life.  Bureaucrats may write into the building code that roofs will not leak.  But roofs do not listen and in time, some will leak.  Therefore treat all timber and gibboard all of the time.

What Treatment?

H1.2 is the new code description which mimics the Boric treatment our fathers used successfully for 50 years.  Ignore H1 LOSP.  It only stops borer.  H1.1 is the new code for finishing timbers that can easily be replaced.  Whilst it is conceded that H1.1 Boric will stop dry rot, it has a limited defence against wet or brown rot. In time the usage of H1.2 will increase and the prices will come down.   H3 Tanalised is a more extreme treatment and is often specialled and sold at a cheaper price than untreated timber.

What not to use?

Never use untreated timber.  It is not fit for purpose. 

Page last updated Tuesday, 08 March 2005