I’ve been laying low on the blog a bit lately while we’ve been doing cut-rate eco-renovations on our house, a poorly insulated 50s fibro place clinging to a steep south-west facing slope, thermally enhanced by a dense cluster of giant evergreen trees perfectly aligned with true north. Short of an avalanche burying the house in boulders or it sliding unexpectedly into the Marianas Trench, it’s hard to imagine a more unpromising scenario for “solar gain”.

Since I’m lucky enough to work from home a day or two a week, seasonally I spend large slabs of time hunched over my laptop in  thermal underwear, jeans, flannie, woollens, scarf, beanie, winter coat and laprug, with my bedsock-and-slipper-clad feet resting ecstatically on a hotwater bottle, thinking obsessively about winter sunlight.

The mid-century part of the house, surprisingly, is pretty well thought through from the perspective of passive solar heating that is (mostly) about allowing the low winter sun to enter the house as source of heat while keeping the overhead sun of summer out.  In the southern hemisphere, that means having windows on the northern side of the house (or within about 30 degrees of true north) and less on the eastern and especially western walls, where the late afternoon sun in summer will blast in the windows just when everyone is feeling at their sweatiest.

So whoever hammered this place together in the late 50s out of asbestos sheeting and weatherboard put in plenty of north-east facing wooden-framed windows that let morning light in through the bare branches of the liquidambar when that glowing ball in the sky finally peeps over the hill.  The kids’ bedroom and the kitchen even have those cool 50s windows that wrap around corners – in this case, oriented to the north.

But it all went pear shaped with the 1980s extension.  Lashings of leaky and thermally conductive aluminium windows and sliding doors facing south-west (towards the view, admittedly – okay, windows aren’t just about solar gain).

Winter sunrise

Summer sunset

The ceiling (and of course ceiling insulation) pock-marked with that latter-day house-cancer, halogen downlights.  And bizarrely, a whole sequence of interior features and outbuildings, aiming, it seems, to prevent even the tiniest gleam of late-afternoon sunlight from melting the icicles on the extremities of the residents inside. Perhaps the previous owners had photophobia: one can only presume so.

In the quest for light-drenched interiors or at least the possibility of taking my hat and overcoat off indoors, mostly what we have been doing is pulling things down and ripping things out.  Renovation by subtraction: cheap entertainment.

First to go was the hand-made bookcase and cabinets that separated the sunny kitchen and the gloomy dining room.  (The wood got a second guernsey as an implausible shoe rack and series of wonky shelves – the previous owners must have spent their years in the dark doing advanced carpentry by headtorch-light, as their skills with a mitre saw are streets ahead of mine).  Never has so much joy or interior illumination ensued from an hour’s work with a screwdriver.

Next we chainsawed a couple of noxious oleanders on the north western side of the house. When I say “we” I mean RB, with me stabilising the ladder, shouting encouragement through a dust-mask, and hoping like hell the chainsaw doesn’t get dropped on my head. Oleander: a plant that is not only water wise and offers a long-lasting floral display but every part of which – leaves, sawdust, flowers, even the honey made from its flowers – can be used to poison your children.  A fine addition to any home.

Just to ensure that no dangerous beams of afternoon winter sunlight might fall on even the windowless exterior of the laundry (itself a protective barrier between the sun’s horrifying rays and the frigid loungeroom) the previous owners erected a dismal tin lean-to, guaranteeing enduring Stygian conditions indoors and out.  Removing the corrugated iron from the roof of this bat-cave was again surprisingly easy – the work of an afternoon – and suddenly what was a dank storage area for rusty things and part-time creek bed became an mid-day suntrap, a pergola simply begging for deciduous vines.  Too easy.

While I continue to harbour many elaborate northerly-glazing and thermal-mass fantasies, further demolition will require council approval and buckets of money, sadly, so I’ve had to content myself with some eco-thrifty upcycling and, of course, plant acquisition.

So…. the kiwifruit arbor!

I have three kiwifruit growing elsewhere in the garden – a male and female “Hayward” and a Mt Tomah red kiwiberry (a bit of a threesome going there, the Mt Tomah quite happy to make do with the Hayward male as a pollinator).  They do a sterling job of sheltering the granny flat from the brutal south-westerly sun on long summer afternoons but I have a sneaking suspicion that we may not have enough chilling hours here to see them fruitful (to wit, absolutely no signs of flowering yet, though we’ve had bunches of grapes from the Pink Iona vine that grows beside them for a couple of years now).

So I acquired a male and female “Sweetie“, a super-low chill variety from the marvellous Daleys, the fastest and best mail-order fruits in the West (okay the East).  The New Zealanders grow kiwis on trellises, and my notion is that the kiwi fruit and the recently planted Carolina Black Rose grape will offer some shelter from the midday heat during the summer and lose their leaves in time to let the low winter sun warm up my ad hoc bench made of bricks and some junked marine ply that sits outside the laundry, an ideal defrosting area on nippy mornings.

Drainage is apparently quite critical for kiwifruit, so, given that when it rains, that part of the yard becomes a water-feature, I decided to put the kiwis in raised planters (with an open base so they don’t dry out too much in less torrential times). Unlike a real bat-cave, the old lean-to didn’t have the benefit of a stockpile of guano but rather hard-beaten gravelly soil, so I figured planters would keep the vines clear of any limey ground and give me a chance to whack some heavy duty compost around their roots.

Fortunately for me, my neighbour decided to re-clad one wall of his house, and we had a bunch of cedar siding thrown helpfully over the fence, so over the course of a weekend, I constructed a pair of 6 foot long, 2 foot wide and high planters from some 2x4s that had been used to frame concrete and an bedframe found in the council cleanup, lined with plastic bags that had previously contained cow poo and finished off with the cedar boards.  I was quite pleased with the result, although given the shonkiness of the carpentry, I doubt I’ll be leaving them to descendents in my will.

The “solar pergola” last year – looking south west

Looking north east

A year down the track, it’s so far so good with the “solar pergola”.  As it turns out, while my Hayward vines, getting very little direct sunlight in winter, lose their leaves quite promptly around the solstice, the Sweeties, in a more promising position, cling to theirs in a rather annoying, shade-producing way.  So I’m trying to constrain their enthusiastic growth to the the far end of the trellis-that-once-was-a-bat-cave where they’ll block our view of the neighbour’s yard but not too much of the June sun.  Keeping kiwifruit vines under control is no mean feat, given their crazed energy and my morbid fear of pruning.  I’ve found grapevines equally prolific but much more compliant in autumn, dropping their leaves just as it gets a bit chilly, so I’ll try to get Carolina to do her fine work above the laundry wall.

It’ll be time for the Sweeties to burst from their buds any day now, and I need to clear the way for Miss Carolina Rose, so I’d better get out into that winter sunshine and prune like the wind!

Later updates from the kiwifruit arbor:

Pollination: Sweets from my sweetie

An unhappy threesome: pollinating kiwiberries

The first bumper crop: Experiments with kiwifruit