Friday, July 12, 2013

Gutters shouldn't be this hard

I suppose I'm partly to blame, but we're having a hell of a time fitting the guttering to the roof.

Normally a roof has eaves and fascia, but being in BAL-FZ our roof is detailed with nowhere for embers to hide and so the roofing tin projects free-span over the Hebel walls, with no fascia or eave lining. This makes attaching gutters a little ... challenging as there's simply nothing for them to affix to in the usual way.

I remember querying Peter about this when I was drawing the 3D model of the building from his working drawings, and at the time I remember him saying there was a type of guttering available which could clip directly to the roofing tin. But do you think I could find anything? It just doesn't exist, unless you want to go for the big ugly square stuff you normally see on the side of .. er ... oh.  Garages.


OK you say, so I may be building a garage, but I don't see it that way :) And I really dislike the big square guttering - in my minds eye I can only see it in Mission Brown, hanging off a dilapidated car port attached to a drab brown brick 70's house. So I've been seeking a Quad profile gutter (the type you see on every Australian house) with a 10mm-or-so return folded into the rear, into which we could screw through the roof.

It Does. Not. Exist.

I had one supplier promise that they could roll me a custom profile, but when I came to enquire further they disavowed all knowledge. So I've been left with free span roofing tin and no way to attach the guttering.

I've been working with Savva to come up with a compromise solution, and today we had a go at installing it. This basically involves a standard Quad profile gutter with a 25x25x1.0mm steel angle screwed to the back to give us our primary support. We're then going to need to clip internal stiffeners to the front of the guttering to prevent it from flopping forward when full, but these are going to have to be screwed on top of the tin in order to work, which is not what they're designed for at all. You guessed  it - they're supposed to be used with eaves!

So while Savva trimmed the roofing tin to give us the required fall towards the downpipes, I set about screwing the angle to the back of the guttering; all 50m of it at 150mm centres. By the time we got around to test-fitting the first length it was getting late in the day (I had been distracted somewhat with my Toll chase) and it was only then that we discovered that it really doesn't work all that well at all. With standard metal screws there's just not enough bite to prevent the screws from pulling out under load, and the stiffeners are .. not stiff enough where it counts, which admittedly isn't quite the geometry they are intended for.

We've decided that with the angle facing backwards there's just not enough stiffness in the geometry to be reliable, but if we screw the angle facing forwards with different, coarser (is that a word!? more coarse) screws it should work. Test fitting one small piece seems to confirm the theory, so we'll go with it.

Did I mention I've already screwed the angle to all 50m of guttering, facing backwards?

Guess what my job for tomorrow is...

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