How should I microwave the Lava Rocks?

The time needed to activate the Lava Rocks is dependent on the strength of the microwave being used. Be sure to microwave the Lava Rocks for half the time listed, turn them over, and resume microwaving the Lava Rocks for the remaining time.

1800 watts: 1 minute each
1500 watts: 1.5 minutes each
1000 watts: 2.0 minutes each

Place the Lava Rocks side by side, on the turntable, in a clean, dry microwave. Heat the Lava Rocks for half of the recommended time, turn them over, and continue heating them for the remaining time. To remove the Lava Rocks from the microwave, grasp them by the gripping tabs located on the sides of the Lava Rocks only. The center of the Lava Rocks will be HOT.

OBSERVE THE PACKS WHILE HEATING.  If any expansion of the pack is observed at any point during heating the microwave MUST BE TURNED OFF IMMEDIATELY.   Allow the expansion to recede before handling.  Do Not heat for more time than is stated.


Why isn't my Lava Lunch staying as hot as I thought it would?

There are a few factors that affect the heat of your food: the strength of microwave, the internal temperature of food, insulation period.

For best results, we recommend heating rocks for the specified time, reaching an internal temperature of at least 160 degrees Fahrenheit and keeping your Lava Lunch closed as much as possible to prevent heat escaping.

What can I do if my Lava Lunch isn't staying hot for as long as I would like?

If you are not achieving the desired results, you may increase the heating time of the Lava Rocks by 30 seconds combined heating time when heating both Lava Rocks together. On day one, try increasing the combined heating time of both Lava Rocks by 30 seconds to see if that resolves the issue. If you are still not satisfied, you may try an additional 30 seconds on day two. Do not exceed 5 minutes of combined heating time.



The Lava Rocks are designed to be heated in a clean microwave. Leftover food particles or grease may cause hot spots which may damage the Lava Rocks and void the general warranty of the Lava Rocks.

Do not heat the Lava Rocks beyond the recommended times. Overheating the Lava Rocks can cause damage to the Lava Rock and may result in damage or injury.

DO NOT expose the Lava Rocks to open flames as the packaging will melt and may catch fire.

Allow the Lava Rocks to completely cool to room temperature prior to heating in a microwave oven or reheating in a microwave oven.

DO NOT leave the Lava Rocks unattended while heating.

DISCONTINUE USE if the Lava Rocks leak fluid during the heating process or if you notice any expansion, or disfigurement of the Lava Rock container.


What If I don't know the wattage of my microwave?

The following test can be used to determine microwave wattage.

  1. Pour 1 litre (L) of cool tap water into a microwave-safe container. Using the thermometer, stir the water for about 10 seconds, then measure and record the temperature. For accurate results, the initial water temperature should be between 60 degrees F (15.6 degrees C) and 80 degrees F (26.7 C).
  2. Place the container in the center of the microwave. DO NOT leave the thermometer in the container. The cooking shelf (tray) or turntable must be in place and any metal racks must be removed.
  3. Heat the water for 33 seconds at full power. Use an accurate digital timer or stopwatch if the oven has a mechanical timer.
  4. After the heating time is completed, immediately remove the container, stir the water for about 10 seconds, re-measure and record the temperature of the heated water.
  5. Subtract the starting water temperature (step 1) from the ending water temperature (step 4) to obtain the temperature rise.
  6. To determine the output power in watts, multiply the total temperature rise by a factor of 100.
  7. The test may be repeated to ensure accuracy

Example: Starting temperature (T1) = 60 deg F; Ending temperature (T2) = 72 deg F; Subtract T2 from T1: 72 - 60 = 12 (temperature rise); Multiply temperature rise by 100: 12 x 100 = 1200 watts

What is the best way to clean and care for my Lava Lunch?

Hand wash with mild soap and warm water. Allow to air dry completely. Do not use bleach. Do not machine wash. Store in a cool, dry place.

How should I pack my food in my Lava Lunch?

While any food container can be used with Lava Lunch we have found that food stays hotter, longer, when food is packed in silicone containers.

Additionally, we have had the best results when placing one Lava Rock beneath your food container, and one on top. Although you may try different configurations. If you are experiencing heat transference to the upper compartment, try placing the Lava Rocks on the sides of the food container, or placing both beneath the container.

Does Lava Lunch come with a warranty?

Yes, it's covered by a 90-day limited warranty. This warranty does not cover damage resulting from improper use, accidents or improper handling. Please email to begin the warranty claim process.

What is your return policy?

If you are unhappy with your Lava Lunch purchase for any reason, you may return it within 30 days of receipt, and we will refund the price of the product. Please email us at for a Return Authorization Number. Returns will not be accepted without a Return Authorization Number.

You will be refunded for the merchandise total, plus applicable sales tax paid, less a re-stocking fee of $3.00. Shipping and handling charges are not refundable unless the product arrived damaged or the incorrect product was shipped. Please allow 14 business days for us to process your return. Please allow 1 to 2 billing cycles for the credit to show up on your credit card statement.

No Exchange Policy

We do not accept orders or items for exchange. If you need a different size, colour or product please return your item(s) for a refund and place a new order at your convenience. Placing the new order now just ensures that you will receive it quickly, and that it won’t go out of stock.

Returning Damaged Merchandise Purchased Online

If your merchandise was damaged in transit or is found to be defective upon arrival, please email to arrange for a replacement. We will ask you to provide photos of the damage for our internal research purposes.


Can I buy the heat packs individually?

This feature is up and coming! Currently, the answer is no but we will be offering this feature in the near future.

Buy Now