Humidity and its Impact on Your Lash Extension Glue, and Why You Need to be SO Vigilant When it Comes to Your Room Conditions.

Finding the best eyelash adhesive is one thing. Knowing exactly how it works in relation to the humidity in your workspace in such detail that you can make adaptations to get it back on track when it’s affected is something else entirely. 

Lash Extension Glue is an absolutely essential part of your lash kit, we all know that, which is why it’s so important that we’re using the right glue for us, and for our relative room conditions. 

The fact of the matter is that regardless which glue you pick and how well it suits your working speed, temperature and humidity both play a huge part in whether your eyelash adhesive works, or fails. Here’s what you need to know…

london lash powerbond glue and clear lash extensions glue

How Does Humidity Affect Glue Performance? 

High humidity = faster drying glue, it’s really that simple. If our humidity level is higher than our glue is happy to work perfectly in, it will begin to cure before you’ve had a chance to apply your eyelash extensions to the natural lashes, and therefore won’t be able to form a strong bond between the two. If you’ve ever brushed through the lashes at the end of a full set and had a lot of fans brush away, this is more than likely the reason.

SIDE NOTE: Why else might you have brush offs?

Humidity will be the culprit if you’re well used to your glue and know how to keep it happy, and if you’ve done a great job of cleaning your client’s lashes, but there are four other reasons that lash extensions brushing off might occur.

  1. You didn’t clean your client’s lashes. Okay, maybe they came in without obvious makeup on and their lashes looked clean, but consider that you can’t see lash serums, remnants of skincare, and little leftover bits of makeup on the lashes. No matter how clean your client looks, you cannot guarantee good retention if you don’t do your Lash Prep!
  2. The glue is too fast for you. Let’s say that your humidity is perfect and your room is a lovely ambient 20ºC. If you bought the fastest, strongest eyelash extensions glue thinking it would change your life, you were right, just not in a good way. There’s a really good reason that we stock six different eyelash extensions glues, and that is because each and every Lash Technician has different needs. Faster doesn’t always mean better, so always time your placement speed before committing to a new lash extension glue. 
  3. Your glue is old. If you don’t pay attention to how long you’ve had your lash glue open for, you’re going to struggle sometimes. Before opening, lash glue has a shelf life of 6 months from the DOP. After opening, you’re best off swapping to a new bottle every 4-6 weeks. If you don’t open your glue very often and you store it perfectly, you can get away with 8 weeks, but be extra vigilant when it comes to storage.
  4. Your glue hasn’t been shaken properly. Failure to shake your glue means that everything separates out. If you’ve ever dispensed glue to find that it’s gray instead of black, it means it hasn’t been shaken properly. Shake your glue for at least a minute before the first use of the day, and for 20-30 seconds before you dispense each dot throughout the treatment. This is of course harder to spot in clear eyelash extensions glue, so be extra careful to shake it perfectly. Invest in a glue shaker to be on the safe side.

Back to our humidity deep dive... 

While high humidity will cause issues with retention, low humidity will make your glue take a long time to dry, leading to extra stickies or leaning extensions which will make your work look untidy. 

eyelash extensions sticking together

What Other Issues Might You Have?

Glue fumes are attracted to moisture, so if the humidity in the air is too low the adhesive fumes will migrate to more moist areas, such as the eyes, nose, and mouth. This isn’t great for you or your client, and will absolutely lead to things like chemical burns and respiratory issues. 

TOP TIP: If you feel that you have an issue with glue fumes in general (it’s not uncommon for Lash Technicians to be allergic to Lash Glue while they’re working), look into a Glamcor Flow, which helps to get rid of fumes without altering the temperature and humidity in your workspace.

It’s also important to note that the longer glue takes to cure, the longer the fumes will last, so it has more of a chance of irritating your client’s eyes. This increases the risk of a chemical burn, which no-one wants!

How Can You Change Your Humidity?

If your humidity is consistently too low, consider investing in a humidifier. Choose it wisely though – if your lash room is bigger, you need a larger humidifier which will cover the whole area, and if you’re working in a smaller space be careful not to buy a humidifier that will make your humidity level way too high.

To increase the humidity in your immediate working area, try adding some little droplets of water along the eyepatch with a micro brush, being careful not to let the water touch the lashes – we don’t want any shock polymerisation

Alternatively, adding Booster to your pretreatment routine to speed up the glue’s curing time and will improve your retention by making the lashes rough and giving the glue more surface area to grip onto. Want to know more about Booster? We have a blog post about it!

an open bottle of london lash booster in a frosted glass bottle with a gold lid. the lid is laying next to the bottle showing the pipette

If your humidity is too high, a dehumidifier would be the best option overall as it will be effective in all seasons. Again, make sure to check that it will work effectively in your workspace. 

TOP TIP: if you’re using a humidifier, keep it away from your lash trolley and your hygrometer. Having it next to your hygrometer will give you a false reading of what your humidity is doing which might mean that you start using your glue in a way that’s not actually helpful, and having it on your lash trolley will give you even more glue issues.  

What About Air Conditioning and Central Heating?

Great question. While they each do a spectacular job of keeping you cool or cozy respectively, they do alter your humidity levels. Both of these can reduce your humidity levels as they alter the temperatures, so just keep a really close eye on what your humidity is doing when you’re altering the temperature in any way. 


In short, humidity can be your eyelash extension glue’s best friend, or mortal enemy. Keep track of your temperature and humidity levels by keeping a hygrometer on your lash trolley and you’ll have one less thing to worry about when it comes to lash retention!