Water, timber can be costly mix to repair

Water damage at mum and dad's farmhouse has resulted in replaced clapboards, spliced-in corner boards, and new flashing. PHOTO/SUPPLIED

FEW things discourage me more than an All Blacks loss or a poorly designed wastewater treatment plant than seeing preventable water damage to a timber-framed home.

As a lover of old homes, I know that water is the ultimate enemy of wood, and all efforts should be taken to exclude water from direct contact with timber.

These efforts include both proper flashing and sealing of the exterior skin of a structure, and adequate splashbacks and sealing around interior plumbing - in both cases, hundreds spent on prevention will save thousands in repair bills.

In my opinion, this is one of the major strengths of the New Zealand Building Code, brought on in all likelihood in response to the legacy of leaky homes.

During our renovation, the building inspector was very strict about ensuring a completely waterproof shell - and rightly so.

I've written before that the most sustainable home is the one that does not fall down in an earthquake, burn down in a fire, or rot from water damage. These are three of the major emphases of the Building Code, and I think building inspectors provide a valuable service in making sure these high standards are adhered to.

As a do-it-yourselfer, I also benefited from some of the "tricks-of-the-trade" advice offered by our building inspector on some of his visits.

I now know for a fact that our home is more durable because our inspector did his job properly. Building consents are by no means cheap, but I believe they will pay for themselves eventually either in terms of the long-term durability of the structure or in the resale value, as a complete inspection comes with a Code Certificate of Compliance.

There appears to be an abundance of homes slowly rotting away across Castlecliff and Gonville. I'm not saying that these are the only suburbs with disintegrating housing, but these are the neighbourhoods I frequent.

Often times, while riding my bicycle from my home near the river mouth to centre city, I tootle along looking at houses. I am particularly drawn to very good design and detailing - and to very bad design and detailing. I'll say this again because it is so important - spending hundreds on preventing water damage will save thousands in repair bills. It is exactly like changing engine oil regularly - paying a little saves a lot. Same goes for insulation.

So, if you are the owner of an old timber home, and particularly if you are a landlord who owns many old timber homes, please have a look at your properties and check the flashing around doors and windows, as well as the external corners.

You'll see in the photos an example of the many scribers I made to seal our home against wind-blown rain.

The scribers pictured are made from treated pine that was cut with a jig saw, primed on both sides and the ends, and then painted twice before nailing in place.

Also pictured are some details of a repair job done to my parents' home (built in 1828) near Boston, United States. You can see that the four lowest weatherboards (we call them clapboards in New England) have been replaced on the left, along with the bottom portion of both corner boards.

Additionally, a new flashing was added at the bottom to protect the sill. Although this repair job cost thousands of US dollars, the builder did a good job to prevent this type of water damage happening again.

Nelson Lebo consults businesses, schools, and home-owners on all aspects of sustainability.