Shade percentage explained: 40%, 80%, and what you actually need
The question I get asked most is which percentage is best. There is no best. A higher number is not automatically better — it depends entirely on what is standing underneath it.
What the number means
Shade factor is the share of sunlight the fabric blocks. A net rated 80% is built to stop roughly 80% of the light and let the other 20% through. It comes from how densely the fabric is knitted, and on a commercial UV-stabilised net it holds that rating for years rather than fading off after one summer.
Shade factor and UV block are two different numbers, and people mix them up constantly. UV block is how much ultraviolet the fabric stops, and it normally runs higher than the shade factor, because the yarn is treated to absorb UV specifically. A net can let visible light through while still cutting most of the ultraviolet. That matters a great deal if you are growing something, and hardly at all if you are parking a bakkie.
One more thing that is not on the spec sheet: colour changes the result. A darker net of the same rating blocks more and sits cooler underneath. A lighter net reflects more heat off the top surface but lets more glare through. Same percentage, different feeling on the ground.
Roughly where each range belongs
| Shade factor | Suits |
|---|---|
| 30–40% | Light crop protection, hardening off seedlings, windbreak work. Rarely the right answer for a parking bay. |
| 50–60% | Nurseries and mixed horticulture, patios where you still want brightness underneath. |
| 70–80% | The workhorse range. Vehicles, staff and visitor parking, walkways, play areas, stock yards. |
| 80–90%+ | Where you want as close to full cover as netting gives — dealership display lots, long-stay fleet parking, seating areas. |
A guide, not a rule. The right answer comes from what is under the net and which way the site faces, which is why I ask rather than assume.
Working it out from what is underneath
- Vehicles. Go high. There is no argument for letting sun onto a dashboard, and nothing underneath that needs the light. This is where most of my work sits.
- People — staff, customers, schools. High as well, but comfort matters: you want the space cool and usable, not dim and gloomy, and that is where colour does as much work as the percentage.
- Stock and equipment. High. Plastic housings, rubber seals and printed packaging all degrade in UV, and none of them need light.
- Crops and nursery stock. This is the one where more is genuinely worse. The plant needs light to grow; you are trimming the harshest part of it off, not shutting it out. The right figure comes from the crop, and it is a conversation, not a default. We do agricultural work, and this is the first thing I ask about.
The honest version
Almost nobody regrets going higher over a parking area, and plenty of people regret going higher over plants. If you are covering something living, tell me what it is before you pick a number.
What else changes the answer
Percentage is only part of it. Two structures with identical netting can perform completely differently.
- Which way the sun crosses the site. Morning and late-afternoon sun comes in low and sideways, under the net rather than through it. A higher percentage does nothing about that — the size and position of the structure do.
- How much you are covering. A net that stops short of the vehicle at three in the afternoon is the wrong size, whatever it is rated at.
- Height. More height means better airflow and a cooler space underneath, and it also means more low sun coming in from the sides. It is a trade-off worth talking through.
- Colour. See above. It is the part people decide last and notice first.
Choosing without guessing
Have a look through the colour range — each one lists its shade factor and its UV block, so you can compare them directly instead of going by the swatch. Then put it on a structure in the configurator and see what the combination actually looks like before you commit to it.
And if you would rather just ask: send me a photo of the site and tell me what is going under it. I will tell you which percentage I would fit and why — and if the honest answer is that your existing netting is fine and only needs re-tensioning, I will say that instead.