If you've noticed your clients' lashes lasting beautifully through the cooler months and dropping faster than expected from November through to March, you're not imagining it — and it's probably not your technique. Humidity is doing it. And in Australia's subtropical and coastal regions, summer humidity is one of the most significant factors affecting lash retention, and one of the least talked about in training.
How humidity affects your adhesive
Cyanoacrylate adhesive — the active ingredient in all professional lash adhesives — cures through a process called polymerisation that's triggered by moisture. A small amount is necessary for the adhesive to cure correctly. Too little and it cures too slowly, creating a brittle bond. Too much and it cures so fast that the bond is compromised before proper adhesion has occurred — a process called shock polymerisation.
💡 In summer, when humidity climbs above 65–70%, the adhesive begins to cure the moment it's exposed to air. Your placement window shrinks dramatically. The result is extensions that shed within days — often lifting cleanly from the natural lash rather than growing out gradually.
What you can change
- Control your room. Run a dehumidifier before and during appointments. Aim to maintain 45–60% humidity. Avoid working with doors or windows open in summer — outside air will constantly push humidity up.
- Switch adhesives seasonally. In high humidity, a slower-curing or sensitive adhesive gives you a larger working window and more reliable bonds. A fast-cure adhesive in a humid room creates its own retention problems.
- Adjust your working pace. In high humidity, work in smaller sections. Replace your adhesive drop every 15 minutes rather than every 20–25.
- Educate your clients seasonally. Exercise, swimming, sweating, and steam showers all introduce moisture to the lash bond in the first 48 hours. In summer, clients are more likely to do all of these. Make the aftercare conversation specific to the season.
Struggling with summer retention? Browse our full adhesive range — including sensitive and slow-cure formulas suited to high-humidity conditions. Pair with a hygrometer to take the guesswork out of your room conditions year-round.
📌 A hygrometer in your room isn't a professional luxury — it's a basic requirement if you want consistent results year-round. Don't guess your conditions. Know them before you open your adhesive for the first client of the day.
