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Free area dossier · Dainfern
A 1990s roofline with 2020s glazing behind it, pointed deliberately at an open fairway. That combination is the whole shading problem here — so here is what the sun does over Dainfern through the year, elevation by elevation, with the trade-offs written down.
Download this guide (PDF, 1.5 MB) to read later or hand to whoever measures up.
01 — The starting point
Dainfern is the estate that started the format. Johnnic Properties took over the old Fourways golf course in 1985, the first Gary Player-designed course on a South African residential estate opened here in 1989, and the township was proclaimed in 1992.[1][2] It now runs to roughly 320 hectares and about 1,200 homes, with the Jukskei River threaded through the layout — the course crosses it six times.[3][5]
The glass points at the course on purpose. Houses run from about 450 m² to over 800 m² on stands of 790–1,600 m²,[4] with the living wing sited for the view. A fairway is open ground: no neighbouring roof, no wall, no street tree between your lounge glass and a low afternoon sun.
The roofline is 1990s and the glazing often is not. Tuscan and Mediterranean-revival houses — render, terracotta, arched openings, wrought iron — many since remodelled with far larger, squarer glazing behind the original roof. One house routinely needs two answers: one shaped for an arched head, one for a six-metre slider.
And the villages differ. Sherwood, Hampstead, Highgate, Montagu and Riverwood[1] carry different stand sizes and window schedules.
02 — The light here
Dainfern sits at roughly 25°59′ south,[1] about 1,753 m above sea level.[6] The published solar geometry for this latitude puts the sun 87.7° above the horizon at noon on 21 December and only 40.84° on 20 June.[7] (Those figures are Pretoria's, at 25.7° south — Dainfern is within a third of a degree.)
That 47-degree swing splits the year. In midsummer a north window with any eave above it shades itself at noon. In midwinter the sun is at 40°, due north, and pours straight in — which, with June minima near 4 °C and occasional frost,[6] is warmth you want rather than warmth you block.
The afternoon is the real problem, and it moves. On 21 December the sun sets on a bearing of 243.35°, some 27 degrees south of due west; on 20 June at 295.76°, north of west.[7] The window that bakes in January is not the one that bakes in June. From three o'clock in summer the light arrives low and nearly horizontal, and the same study is explicit that western afternoons run hotter than eastern mornings.[7] An overhang cannot block a horizontal ray: west glass needs something at the pane or outside it.
03 — Room by room
Same house, four different problems — work out which wall a room sits on first.
North carries the sun all winter: high enough at midsummer noon that an eave does the work, then at 40° and driving deep into the room by June.[7] These rooms want something you tilt, not something you close.
Verdict: adjustable beats absolute.
Low, near-horizontal light from three o'clock — 27° south of west at midsummer, north of west in winter[7] — with nothing outside a fairway-facing lounge to break it. An interior blind fixes the glare at once and the heat only partly: once the sun is through the pane the energy is in the room.
Verdict: stop it outside the glass if you can.
The same geometry mirrored, into a house that cooled overnight. In December the sun clears the horizon at 116°,[7] so an east bedroom is lit long before anyone wants to be awake. Blockout in the bedroom, then, and something you can see through in the kitchen.
Verdict: solve for sleep and glare, not heat.
Almost no direct sun most of the year: the steadiest light in the house, and the coldest room in it once June arrives with 4 °C nights.[6] Heat loss and being overlooked are the problems, not sun.
Verdict: think warmth and privacy.
Optional
Tell us which rooms are the problem and we will send you this same dossier with your own elevations noted against it — which windows we would treat first, and what we would be weighing up on each one.
It is an email, not a visit. Nobody phones you about it.
04 — The specification
Each is right somewhere in a Dainfern house and wrong somewhere else in it. Whatever you add here waits on the form below.
One flat sheet of open-weave fabric on a tube: it cuts the glare and a useful share of the solar gain while the course stays visible through the weave.
It reverses after dark — lights on, and you are the one on display. Where a cart path or a neighbour is close, pair it with a blockout on the same window.
A single smooth sheet with no light through it, sitting cleanly inside a modern square reveal. Against a December sunrise on an east bedroom window, the most effective thing there is.
Binary — down is dark, up is everything — so wrong for a north living room. Without side channels, light always finds the edge of the reveal.
Rigid aluminium slats rolling down from a headbox outside the building. On hard west glass we would specify these over an interior blockout roller for one reason: stopping the heat outside keeps a room cooler than absorbing it inside, where the pane warms and radiates all evening.
Shading, not security. Everything they do — sun, heat, glare, light — happens outside the glass. A security rating is another product altogether, quoted on request.
The most visible exterior change here, and the headbox has to live somewhere: on a render facade, a design decision rather than a measurement.
An awning's canopy rides out on hinged arms with nothing standing on the paving, and handles sun from above. It does almost nothing about a low western sun arriving sideways at five — which is what a zip screen is for: flat mesh held tight in vertical side channels so wind cannot flap it or lift it out.
The awning is the bigger visual change; the screen filters rather than blocks and will not make a patio private after dark. Both live outdoors in a hail belt, with storms most summer afternoons,[6][8][9] so we fit a wind sensor rather than trust anyone to be home.
Flat wooden slats you tilt rather than open or close — exactly the control a north wall wants: bounce high summer light off the ceiling, then open flat in June.
Heavier and dearer than aluminium, and a wide opening splits across more than one headrail. Above a bath or a scullery sink choose aluminium; timber and steam age badly together.
The windows nobody reaches are the ones cooking the room. A timer that drops the whole west side at three o'clock does more for comfort than any fabric choice, because it happens whether you are home or not.
Rechargeable motors retrofit without chasing walls but need charging twice a year; wired ones never do, and mean opening a ceiling.
Five more sit on the form below: cellular honeycomb (a winter gain, not a west-glass one), day/night blinds (privacy, never fully dark), aluminium venetians where steam would ruin timber, panel blinds for a wall too wide for slats, and skylight and shaped blinds for arched heads and raked gables.
05 — The local constraint
Dainfern has been run by its Homeowners Association since management transferred to it in 2000; the DHA has existed since 1991 and became a not-for-profit company in 2014.[2] Like any estate it takes an interest in the outside of a house, which divides cleanly:
We will not quote your rule at you: Dainfern's guidelines go to residents through the estate's own channels rather than being published, and villages are not identical. Check yours first. What we can do is put the profile, colour reference, projection and fixing method in writing for your submission.
Renovating? SANS 10400-XA:2021 (Edition 2) requires a fenestration calculation once glazing passes 20% of floor area — it was 15% in the previous edition.[10][11] If you are pushing more glass toward the course, ask your architect early how the shading is being counted.
06 — The honest limit of a dossier
What no guide knows is your house. Five things settle the specification once we are in the room.
Depth decides whether a blind fits inside the opening at all; on an arched head we also need the exact spring point. A 12 mm difference top to bottom is normal on rendered work, and it changes the blind.
We take a compass reading at the window: twenty degrees moves a recommendation between west and south-west. Then we look out of it — a fairway, a treed river edge and a neighbour's gable each shade a room differently.
Render over brick, render over block, a stud bulkhead, or a plastered arch with nothing behind it where you want a bracket. For anything exterior, that decides whether the job is possible at all.
For double-volume or clerestory glass, the route from a power point to the head of the window is the constraint — a walk-around with a torch, not a guess over the phone.
A sheltered courtyard and an open corner facing down a fairway need different projections, fixings and sensor settings — settled in two minutes on the paving.
07 — Two ways forward
A consultant comes to the house with fabric and slat samples, measures every opening properly, looks at where the sun actually lands, and leaves you with a written quote priced window by window. None of it costs you anything, and none of it obliges you to order. If you would rather have a rough number before anyone visits, the ballpark list sits underneath the form and does that instead.
Anything you added while reading is already ticked on the form. You do not have to type it again.
Neither, for now
Not ready for a visit or a number? Tell us which rooms are the problem and we'll email you this dossier with your own elevations noted against it. Nothing is booked and nobody phones.
Working out
Every geographic, climate, estate and regulatory claim above traces to one of these. Where we have reasoned rather than cited, we have said so in the text.
Four honest caveats. The solar figures in source 7 are calculated for Pretoria at about 25.7° south; Dainfern sits at about 25.98° south, so its own angles differ by well under half a degree — we have quoted the published figures rather than invent our own. The hail paper prints its peak hours in UTC; the "three in the afternoon to seven in the evening" conversion to South African time is our arithmetic, not the authors'. All hail and storm figures are Highveld- and Gauteng-wide, because no suburb-level data exists. And we could not find Dainfern's architectural guidelines published anywhere public, which is why this dossier tells you to check your own village's rules rather than quoting one at you.
Next
Free in-home measure, samples in the light of the room, and a written quote priced window by window before anything is made.
For later: download this guide.
