Can LEGOs Melt in the Sun? (When Do They Melt?)

*This post may contain affiliate links. As an Amazon Associate we earn from qualifying purchases.

You’re building your dream LEGO city on a sunny summer afternoon, feeling like a master architect, when suddenly you notice something off. Are your LEGO bricks beginning to… melt?

If you’ve ever experienced this, or even just thought about it happening, then this article is perfect for you! We’ll dive deep into the world of LEGOs and sun exposure, addressing all your burning (pun intended) questions with a pinch of humor and a dash of science.

So can Lego’s melt in the sun?

Legos will not melt in the sun as the ABS that Legos are made of doesn’t start to melt until it reaches 221 degrees. However, Legos can begin to warp at temperatures of 131 degrees which the concrete/asphalt can reach if you live in a hotter area of the country/world. 

Having trouble with melted or warping LEGOs? No worries, we’ve got your back! So buckle up and prepare to become a LEGO-sun expert, as we unravel the mystery of Lego’s and the sun.

Overview of LEGO Materials

Ah, LEGOs! Those wonderful, colorful, and infinitely versatile plastic bricks that have entertained generations. But what are they made of, exactly? Let’s explore the secret sauce behind LEGOs’ magic.

LEGOs are primarily made of acrylonitrile butadiene styrene (ABS) plastic, which is known for its strength, durability, and resilience. ABS is like the Superman of plastics, a fitting material for our beloved toy bricks.

ABS plastic is a real triple-threat in the world of materials:

  • Impact resistance: It can take a beating and bounce back, just like your favorite action hero.
  • Glossy finish: ABS plastic has a natural shine, perfect for showcasing your LEGO masterpieces.
  • Easy to process: LEGO can easily mold ABS into bricks with tight tolerances, ensuring a snug fit for building fun.

Durability and safety are crucial in the LEGO universe. With millions of children (and adults!) playing with LEGO bricks daily, they need to withstand the test of time, as well as various temperatures, and forces. LEGOs are designed to last, ensuring they can be passed down from generation to generation.

Melting Points of LEGO Materials

Now that we know what LEGOs are made of, let’s delve into the critical question: at what temperature do these bricks start to resemble Dali’s famous melting clocks?

The melting point of a material is the temperature at which it transitions from a solid to a liquid state. For LEGOs, the melting point determines the conditions under which they can maintain their shape and functionality.

ABS plastic has a melting point of approximately 221°F (105°C). This might seem high, but remember, we’re talking about melting, not just softening or warping.

In reality, ABS can begin to lose its structural integrity at temperatures lower than its melting point.

To put things in perspective, let’s see how ABS plastic stacks up against other common plastics:

  • Polyethylene (PE): 248°F (120°C)
  • Polypropylene (PP): 320°F (160°C)
  • Polystyrene (PS): 464°F (240°C)

As we can see, ABS has a relatively moderate melting point compared to some other plastics.

Effects of Sun Exposure on LEGOs

Now that we know the melting point of ABS, it’s time to ask: what happens when our beloved LEGO bricks are left under the scorching sun?

UV rays from the sun can have several effects on LEGOs:

  1. Color fading: UV rays can break down the color pigments in the plastic, causing them to fade over time. Say goodbye to your vibrant LEGO city and hello to a pastel wonderland!
  1. Brittleness: Prolonged exposure to UV rays can cause the ABS plastic to become brittle, making your once indestructible LEGO bricks prone to breakage. Snap, crackle, pop—and we’re not talking about cereal!
  2. Warping: While not directly related to UV rays, the heat from the sun can cause LEGOs to warp, making it harder to fit them together. It’s like trying to solve a puzzle with pieces that just won’t click!

To provide a clearer picture, let’s dive deeper into the various structural changes that sun exposure can cause to your LEGOs:

  • Color fading: As mentioned earlier, UV rays can cause the vibrant colors of your LEGO bricks to fade, turning them into a sad, washed-out version of their former selves. It’s like leaving your favorite shirt in the sun for too long—except way more heart-wrenching.
  • Surface degradation: UV rays can break down the molecular structure of the ABS plastic, resulting in a rough, uneven surface texture. It’s akin to your LEGOs developing a bad case of sunburn and peeling.
  • Cracks and breaks: Sun exposure can make your LEGOs more susceptible to cracking and breaking under pressure. It’s like turning your once tough-as-nails bricks into fragile little snowflakes.

Fear not, fellow LEGO enthusiasts! There are ways to protect your precious bricks from the evil clutches of the sun:

  • Store your LEGOs in a cool, dry place, away from direct sunlight.
  • Use UV-resistant cases or displays for your LEGO masterpieces.
  • Rotate your LEGO sets occasionally to avoid prolonged exposure to sunlight.

Temperature Thresholds for LEGOs

It’s time to get technical and talk numbers. What’s the temperature range in which LEGOs can maintain their shape, and what happens when they’re exposed to extreme temperatures?

LEGOs are generally stable and maintain their shape within the following temperature range:

  • Minimum: 14°F (-10°C) – Say goodbye to frozen fingers while building your LEGO snow fortress!
  • Maximum: 104°F (40°C) – It’s getting hot in here, but your LEGOs can still handle it.

When LEGOs are exposed to temperatures beyond their safe range, you can expect some interesting results:

  • Below minimum: LEGOs become more brittle and prone to breakage. It’s like turning your bricks into ice sculptures—one wrong move, and they shatter.
  • Above maximum: LEGOs may soften, warp, or even melt. Imagine your LEGO city slowly sinking into a colorful plastic puddle. Yikes!

Rapid temperature fluctuations can be particularly harmful to your LEGO creations:

  • Expansion and contraction: Constantly changing temperatures can cause the ABS plastic to expand and contract, leading to weakened connections and loose bricks. It’s like playing Jenga with a wobbly table.
  • Increased stress: Temperature fluctuations can put stress on your LEGO structures, making them more likely to collapse under pressure. It’s a literal house of cards situation.

Can LEGOs Melt in the Sun? (When Do They Melt?)

We’ve covered the science and the numbers, but let’s get to the heart of the matter: Can LEGOs actually melt in the sun? And if so, when do they melt?

While it’s not impossible for LEGOs to melt in direct sunlight, the odds are relatively low. The melting point of ABS plastic is 221°F (105°C), which is much higher than the average outdoor temperature in most locations.

However, some factors can increase the risk:

  • Location: If you live in an area with scorching summers and intense sunlight (hello, Death Valley!), your LEGOs might be at greater risk.
  • Surface: Placing your LEGOs on a dark, heat-absorbing surface (like black asphalt) can cause them to heat up more quickly.
  • Enclosed spaces: Leaving your LEGOs in a closed car on a hot day is like putting them in a mini oven. Temperatures inside a car can skyrocket, putting your bricks in the danger zone.

Various factors can influence the likelihood of your LEGOs melting in the sun:

  • Latitude: Areas closer to the equator generally experience more intense sunlight and higher temperatures.
  • Altitude: Higher altitudes can be associated with increased UV radiation and temperature fluctuations.
  • Climate: Hot, arid climates pose a greater risk to your LEGOs than cooler, temperate regions.

While rare, there have been instances of LEGOs meeting their melty demise:

  • A LEGO enthusiast in Arizona reported that their outdoor LEGO display warped and softened during a particularly brutal heatwave.
  • In a tragic tale from Australia, a beloved LEGO collection left in a closed car on a sweltering day transformed into a gooey, unrecognizable mess.

Preventing LEGO Melting and Damage

Now that we’ve explored the potential dangers, let’s discuss how to protect your precious LEGO bricks from the ravages of sun and heat.

Keep your LEGOs safe and sound with these storage tips:

  • Avoid direct sunlight: Find a cool, shady spot to store and display your LEGOs.
  • Use airtight containers: Storing your LEGOs in airtight containers can help protect them from temperature fluctuations and humidity.
  • Keep them indoors: As tempting as it might be to create an epic outdoor LEGO landscape, it’s best to keep your bricks safely indoors.

Maintaining a stable, temperature-controlled environment is key to preserving your LEGO bricks:

  • Prevents warping: Keeping your LEGOs in a consistent temperature helps prevent expansion and contraction, which can lead to warping.
  • Preserves color: A temperature-controlled environment can minimize the risk of color fading due to UV exposure.
  • Extends lifespan: Your LEGOs will thank you for keeping them in a comfy, climate-controlled space by lasting longer and staying in better condition.

For added protection, consider investing in some LEGO armor:

  • UV-resistant cases: These cases shield your LEGOs from harmful UV rays, preventing color fading and surface degradation.
  • Display cabinets: Glass or acrylic display cabinets can protect your LEGO masterpieces from dust, humidity, and temperature fluctuations.
  • Anti-UV coatings: Some enthusiasts swear by applying a clear, UV-resistant coating to their LEGO bricks to preserve their colors and integrity.

Repairing Melted or Damaged LEGOs

Has the unthinkable happened? Are your LEGOs warped, melted, or damaged? Fear not! We’ve got some repair tips that might just save the day.

While some damage may be irreversible, there are a few techniques you can try to salvage your bricks:

  • The Freeze-and-Fix Method: Place your melted LEGO bricks in the freezer for a few hours. Once they’re cold and solid, carefully reshape them back into their original form. It’s like giving your LEGOs a chilly spa treatment!
  • Brick Surgery: In cases of severe damage, you might have to perform some LEGO surgery. Grab a sharp hobby knife, gently trim away the melted or deformed parts, and reconnect the remaining pieces. It’s like performing delicate plastic surgery, but with tiny bricks instead of human body parts!

Now, let’s face some hard truths. Not all LEGO damage can be reversed. Here are some limitations to keep in mind:

  • Structural integrity: If the melted LEGO bricks have lost their structural integrity or fused together, there’s not much you can do. It’s like trying to unscramble an omelette back into eggs—nearly impossible.
  • Color restoration: Even if you manage to reshape melted LEGOs, the color fading caused by UV exposure is irreversible. No magical potions here, I’m afraid.

Sometimes, it’s best to say goodbye and move on. Here’s when you should consider replacing damaged LEGO bricks:

  • Safety concerns: If the damage compromises the stability or safety of the bricks, it’s time to retire them. Safety first, folks!
  • Aesthetic integrity: If the melted or warped LEGO pieces no longer fit seamlessly into your creations, it’s worth investing in fresh bricks. Maintaining that LEGO perfection is essential!

Frequently Asked Questions about LEGO Melting

Now that we’ve covered the nitty-gritty of LEGO melting, let’s address some burning questions and common misconceptions.

Don’t let these misconceptions melt your brain! Let’s set the record straight:

  • Misconception: “All LEGO bricks will melt in the sun.”
  • Reality: While extreme heat can damage LEGOs, they won’t spontaneously transform into colorful puddles. The melting point of ABS plastic is higher than your average sunny day.
  • Misconception: “LEGOs can only melt outdoors.”
  • Reality: Sunlight isn’t the only culprit. High temperatures indoors, like in a closed car or near a heat source, can also pose a risk to your beloved bricks.

Let’s answer a few more burning questions to satisfy your LEGO curiosity:

Q: “Can I use a hairdryer to speed up the LEGO drying process if they get wet?”

A: Absolutely! Just make sure to use the cool setting to avoid melting your bricks unintentionally. Think of it as giving your LEGO friends a spa blowout!

Q: “Do all LEGO sets have the same resistance to melting?”

A: LEGO sets are made from the same ABS plastic, so their resistance to melting is generally consistent. However, keep in mind that larger, more complex builds may be more susceptible to warping or damage due to their size and structure.

Q: “Can I use LEGO bricks in hot climates like the desert?”

A: Absolutely! Just take extra precautions by storing your LEGO collection in a temperature-controlled environment when not in use. Desert adventures with LEGO creations are still on the table!


Phew! We’ve delved into the magical world of LEGO bricks, explored the effects of sun exposure, and even learned a thing or two about LEGO repair techniques. Now, armed with this knowledge, you can confidently build your LEGO empires without fear of them melting away.

Remember, while LEGOs can withstand extreme temperatures to a certain extent, it’s always best to protect them from prolonged sun exposure and keep them in a cool, dry environment. And if the unthinkable happens and your LEGOs do melt, don’t fret!

There are repair methods you can try, but sometimes it’s just best to bid farewell to the damaged pieces and welcome new ones into your collection.

So go forth, LEGO enthusiasts, and let your creativity soar! Build towering skyscrapers, epic spaceships, and fantastical worlds. Just make sure to keep an eye on those LEGO melting points and give your bricks the love and care they deserve.

Happy building!

Now, if you’ll excuse me, I have an irresistible urge to dig into my old bin of LEGO bricks and embark on a nostalgic adventure. Remember, LEGO building isn’t just for kids—it’s a timeless joy that brings out the inner child in all of us.

Embrace the excitement, revel in the frustrations, and let your imagination run wild. The world of LEGOs is your oyster—now go out there and create something truly brick-tastic!

Disclaimer: No LEGO bricks were harmed in the making of this essay. However, the author may or may not have experienced moments of pure joy and nostalgia while writing. LEGO enthusiasts, unite!

Matthew R

Hi, My name is Matt and I am all about toys! When trying to find accurate information online about toys I was finding it difficult so I decided to make this site.

Recent Posts