Well, looking back to last year’s blog, now that I have horrified you all with the realities of a bad foundation choices, take solace from the fact that any good Architect or Designer of any merit or any good experienced and knowledgeable builder will help you through this minefield. It’s a matter of finding the best people for your job, who you are going to completely trust to spend all or most of your money, in the biggest purchase of your life, that will likely leave you with a mortgage, that will take years to pay off (if ever in Auckland) that will be also the biggest of your life to this point…………. no pressure then, so let’s move on!
Now we all have seen the glossy pictures and the flowing layouts that are the bread and butter of “good design”, but have you really given any thought to the bits you can’t see in those pictures. The wall framing, the insulation, the services and the wall finishes.
All these items in the market are produced either for price, ease of assembly or durability, and either you or your professional have to navigate these choices very carefully if you don’t want to be repeating this aspect every 10 years or so.
Let’s take framing for example, on the face of it a pretty straight forward aspect of building in NZ, with choices in either timber stick, steel stud and or concrete walls in the form of masonry or precast/insitu concrete panels. All good so far, these items have been used for years…..with varying levels of success!
Note: All these types of structure must meet the 50 year durability standard required by the New Zealand Building Code, as they are structural members that are not at all easily replaced.
So then why the most does commonly used version of framing in NZ, being H1.2 Timber framing, only come with a 5 year warranty? Even H3.2 only comes with a 25 year warranty. And in addition all water soluble protection, washes off in the rain when it’s being built? Who covers it for the other 45 years of structural guarantee required to meet the building code…….as the owner, you do!
The builder, council and all other trade have to provide 10 years warranty against major failure, so you should be thankful you’re now only having to cover it for 40 years, whew for a moment I thought you were totally screwed……………wait a minute?
Remember that’s just the framing, then we get to insulation. There are several types, fiberglass (the most common), wool, polyester, polystyrene and papier mache. Fiberglass – this product is a very good insulator of heat within the wall cavity, and comes in pretty colours of pink and or brown, however fiberglass is also hydroscopic, meaning it absorbs water and water vapor and when it does it loses all insulating properties and it sags with the weight of the water in the cavities and become useless as insulation. Now not meeting its 50 year requirement. The way they get around this is to provide a guarantee that it has a life time warranty, provided it doesn’t get wet. The chances of water vapor getting into a wall using standard NZ building construction = 100% of the time, so what’s that guarantee really worth? Wool is not much better and expensive, rigid polystyrene is very hard to fit correctly into the frames and any gaps are just heat/insulation leaks. A study I saw said that a gap the equivalent of a saw cut across a sheet of Gib halved the walls insulation properties, so it doesn’t take much to undo all that good. Yet there is so little consideration given to this aspect of the build, even though it has the power to save the owner thousands of dollars……..oh and keep them warm and healthy!
Several spray in insulations have come to market recently which are achieving really good results and along with a water vapor internal membrane is the proper way forward.
Then we get to the wall linings, both exterior and interior. I have covered exterior wall linings before so will focus on internal wall linings this time. Although this is not a critical aspect from a health or structural point of view, durability should be the focus of this section, along with maintenance.
Plaster Bd in whatever form is the dominant NZ internal wall lining. It’s relatively cheap to install, finish and maintain. Well that’s the skinny that the industry markets.
However have you ever noticed that plaster board ceilings are always shiny around the lights? This is where the fly poop and when you wipe the poop away you polish the ceiling paint up, and it goes from Matt to a semi-gloss type finish. The only way to remedy this is to re-paint the ceiling – full stop. If on the other hand you use a plywood ceiling, with a good oil, you spend maybe $10 per m2 more initially.
But you don’t have to wipe off the fly poop as the oil has anti insect repellants and even if there is an issue the oil can be touched up seamlessly to maintain. To repaint a ceiling is approx. $30 per m2, so after the first repaint, you are $20 per m2 ahead if you chose the plywood (or other timber alternative) which also appears to the layman as a very expensive ceiling. It’s just a matter of looking that bit further down the path of the material life to see if there are benefits.
I’ll finish by saying that although I’m not a “fanboy” of the white on white colour schemes that seem to be in every NZ home (black white or alabaster, or half tea with a twist etc etc) I do believe that you do need at least one truly white wall in nearly every room, so you have a consistent colour gauge for the other colours in that room. It was a philosophy initiated by Richard Neutra in his teachings that I have always respected and has always worked in my career.
I’ll leave the services and other fun stuff till next time.
Next Time……
More of the middle
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