Build update: Our house reaches puberty

In which we pass a major milestone - the roof goes on. I delve inside the process from beach to installation, and present a wicked time-lapse video of the event. Also an expose of what sort of power tools actual builders use. And Gemma and I discover a problem with the house that we hope can be solved. 

A roof is the most elemental part of a building. It provides the shelter. You don't talk about living in a house as "having walls around you" but you do talk about "having a roof over your head". Nobody ever said "not while you're living near my walls!" and when you want a party to go all the way to 11 you don't say "Let's lower the floor!" That is why our house just did the house equivalent of going through puberty by having its roof put on. Now it's a stinking teenager.

Gemma and I didn't have too much to decide as far as the roof went. People have been building roofs in New Zealand for a very long time. (And people have also been spelling it "roofs" but saying it "rooves" which is just weird.) Amish people get together as a community to build a roof for a family who need one. We are not Amish so we have contractors: just as good, really, and nobody has to drive a horse and cart and believe the earth is 4000 years old.

Full of excitement at seeing one of the biggest one-day changes in the build, I turned up with my timelapse camera on Monday and found Callum, Ashley and Liam from Metro Roofing already prepping the place.

In the background you can see the camera set up for the time-lapse (which by the way did not turn out to be at all underwhelming).

Gemma and I had chosen a black roof for the house originally and all our drawings had been that way.

This is the mockup we made last year of how we expected the roofline of the house to look from the Neighbours' point of view. We showed it to them to assure them they would still have a view. It's interesting to compare this view to how it actually came out, which can now be seen.

Actual house oriented in a different direction than mockup. I hope we don't have to fix this later.

Hopefully they're happy enough.

But our contractor Rob was on the phone after he had measured the place up to let us know that black roofs are "talkative". We knew just what he meant, having stayed the night once for a wedding at a lodge up north where the roof made a hell of a creaking, cracking and ticking noise every time it warmed up or cooled down. Rob suggested we choose a different colour, one that wouldn't get so lippy. Deciding that a light colour was OK, we chose a colour called "Gull Grey" (a million gulls can't be wrong).

Our roof comes from Roofing Industries. It's a long supply chain.

1. Our roof started as a beach somewhere near Auckland.

A giant child's giant sandpit. Watch out for giant cat turds!

New Zealand steel (who make 650,000 tonnes of steel a year and export most of it) turn sand to steel and make massive coils of flat steel sheeting. Normal "galvanised iron" is just zinc coated, but what they call "Zincalume" is coated with a zinc/aluminium alloy to give it better corrosion resistance.

2. Pacific Coil Coaters then paint the rolled steel with one of a number of special baked-on paint products. Ours is called ZR8. It of course comes in all sorts of colours. This painted product is now called Colorcote. So many brand names.

3. Roofing Industries then take the Colorcote and "rollform" it with massive longform rolling machines into one of their "profiles" depending on the application. One of the main uses nowadays for corrugated iron isn't even for roothes, it's for cladding for $3 million houses to give them that dressed-down casual "bach" feel - for the same sort of people who buy Karen Walker gumboots. 

There is a lot of science to metal roofing that I don't fully understand. For example, two different sorts of metals in contact with each other will cause one of them to corrode badly. For that reason all the fixings, screws, nails, flashings etc that will touch the roof must be made of all the same materials. Different sorts of materials must be kept strictly separated - it's the same sort of principle behind the Pakeha Party.

The profile you choose depends upon a lot of things like how steep your roof is and how windy your area is and the look you are after. We've gone for one called Trimrib. I liked this because it was the one that sounded most like a tasty bit of meat. Here is the profile:

Trimrib can have either one swage (top) or two swages (swaves?) between the ribs. We were unsure how to properly pluralise swage so we chose just the one. I think we made a good swaging saving.


It only took a day for Callum, Ashley and Liam to install the roof. I arrived after they had already laid down the chicken wire.

The next layer is bituminous self-supporting building paper like this.

For "paper", this stuff is pretty high-tech. It is breathable but waterproof (to a certain extent) like a Goretex jacket. It's self-supporting but the chicken wire goes underneath it. I'm not really sure what the chicken wire is for if the paper is self-supporting. I can only assume it's so that no chickens will be able to get into our house through the roof - which does take a load off my mind.

Next Callum and Liam measure the steel, carry it into place and screw it down.

Meanwhile Ashley spent a lot of time just standing on the pile of steel so the wind wouldn't pick pieces up and take anyone's head off. To be honest, after hearing stories of the damage flying steel does, I kind of wanted to see it fly up and sever a tree trunk, but Ashley was too good.

A pile of steel just this big was enough for the whole roof.

To get around obstacles like the skylights, they just do what you or I would - measure and cut.

Then using a special tool the ends are bent up at the tops (and down at the bottoms) so that water doesn't blow up under the flashings and get on the paper.

Pressing down with this bar slipped over the end of the steel gives upstands like this.

This roof laying is a pretty primo job. In the right light it looks fully epic.

Fully epic, lol.

So here is the time-lapse. Enjoy.

Thanks to our next-door neighbours Ros and Ian and their daughter Candice for letting me use their balcony for this time-lapse video, and going above and beyond by saving my camera from the rain when I'd gone back to work and left it clicking away. At the end of this blog, sub-Beebo, I give the technical details of how I do the time-lapses for any camera nerds who want to nerd out about apertures etc.

I came back that evening to get my camera. The roof was done, and as far as I could see in the dark it looked great.

I was stoked to see the house is already keeping the rain out. And no sign of chickens.


When buying powertools and wondering which cordless drill will properly burr the heads on all my screws, which sander will coat all the surfaces in the room with a layer of fine sawdust and which circular saw will properly remove 3mm from each of my fingers, I always wonder what sorts of tools the REAL builders use, so I did a quick tour of the building site to see what Sam and Deek have bought. Here's a gallery:

Talking to them they seemed pretty relaxed about what sort of tools they use, though they didn't hesitate to say that De Walt are the best, and I did hear them teasing the roofers about using a Black and Decker drill, expressing surprise that it was still going. But they have also been impressed with the Ozito (cheapy) drill they bought expecting it to conk out after one use - it's still going years later. So overall I've learnt that unless you are a pro or at least a constant amateur, just get the cheapest one.

However, if you really want to build like the pros, the actual secret I discovered is that you must always keep a massive hoard of big flat pencils. Here's Sam and Deek's stash that I discovered.

Like Smaug guards a pile of gold, Sam and Deek hide this pencil treasure.



Gemma and I stepped on to the top floor of our house last weekend after having been to meet our aluminium joinery supplier Peter (at Rylock).

Gemma makes long-suffering joinery supplier write down everything she says.

Thanks to all you amazing commensters for your input into our dilemma last week about what sort of glass and joinery to choose. Here is what we've gone for: double-glazed, laminated glass in normal joinery. We have been advised that the low-E glass might be hazy and we don't want to risk that. And despite a weight of people recommending thermally broken joinery, we have decided not to. First, it is 40 per cent more (and that's 100 per cent more than we can afford) and, second, we don't think it's necessary in Auckland. We know: condensation! However, condensation happens if there is a large difference in temperature between the inside and outside of the house AND if the air inside is damp. Damp air is the symptom rather than the disease (again like the Pakeha Party) and you can't cure damp air with joinery - you can only hide it by not making it condense on the aluminium. So now we are working on a ventilation solution to make the air in the house dryer (so far tricky due to our pesky skillion roov).

Armed with knowledge of our aluminium profiles we visited the house and were a bit alarmed to realise that this beam which supports a big sliding door that opens the kitchen/dining area on to the deck, will have aluminium frames that are suspended about 100mm below it.

The beam isn't all that high, and with the aluminium framing sticking down below, we decided it was going to be too low and cut into our view more than we would like. 

Idiot indicates where his hair gets to if he removes humorous hat.

It's one of those things that is very hard to tell from plans and elevations, but really clear once it's welded in place. In our amateur opinion there was room to lift it up.

Chump wishes he had just taken a picture of the beam instead of this entry into the 2013 Douche of the Year competition.

So though we knew a big change like this would have implications for the neighbouring windows, the clerestory windows above and a cost as a variation, we decided to ask draughtsman Karl, engineer Bruce and project manager James to investigate before the windows were finally ordered.

I'll let you know next week if they can do it for us, and if so how much it will cost. Any guesses? 


Thank you once again for reading. Big love to all the commentsters - I try to get time to write answers.

Until next week I remain


Purchase Man.


As usual please feel free to "Like" this blog's page on Faceingbook, which will bring you all the joy of an alert when a new posting is blogged. And email me whenever you feel like it for no reason at all. I am proud now to present the first pages of the next book in the Beebo series. Enjoy!


*Time-lapse details: EOS 550D Tamron zoom lens set wide at about 28mm (once the crop factor is accounted for) with the Magic Lantern software hack which adds an intervalometer to the functionality and allows you to choose how frequently a photo is taken. I then set it up on a tripod and set the exposure on manual with a f15 aperture and 1/80th of a second exposure, taking a photo every 15s. Some instructions can be found here.

As always I used iMovie to edit together the video, each still lasting .1 of a second, then laying a sweet Alan Parsons Project tune over the top and exporting it in 1920 x 1080 full HD. Then the rain came and ruined it all. Enjoy.

If you want to you can do a time-lapse with your iPhone. It'll be better than mine. Get a tripod and one of these apps.