A Retes stack, also known as a basking stack, is a term commonly used in the reptile-keeping community, particularly for monitor lizards such as the ackie monitor. It refers to a multi-tiered, elevated basking unit designed to provide a gradient of heat and hiding spots for the monitor lizard. The concept was developed by Frank Retes and has gained popularity among reptile enthusiasts.
As an Amazon affiliate, we may earn commissions on purchases of eligible products.

The main purpose of a Retes stack is to offer the monitor lizard a range of temperature options and secure hiding places. It consists of stacked flat wood or stone pieces with spacers in between, creating crevices and platforms for the lizard to climb on and bask. By having multiple levels, each with different temperatures, the monitor lizard can choose the preferred basking spot while being partially obscured.
Constructing a Retes stack requires careful planning and consideration. Plywood is often recommended over stone for safety reasons, as stone stacks can potentially harm the lizards. The layers of the stack are usually angled to create tight crevices for the lizards to wedge into, providing a sense of security. The goal is to create a graduated temperature range and offer the lizards ample choices for basking.
When building a Retes stack, it is essential to ensure it rests on the floor of the enclosure to prevent the monitor lizard from burrowing underneath and potentially getting injured. The stack should be sturdy and securely assembled to avoid any accidents.
Reptile owners who have implemented Retes stacks in their enclosures report positive experiences, with their monitors frequently utilizing the various levels and gaps provided. However, it’s important to note that the specific design and construction of a Retes stack can vary based on individual preferences and the needs of the particular species being kept.
How to build a Retes stack
Building a Retes stack requires some basic supplies and tools. While there are variations in design and materials, here’s a general overview of the construction process:
- Choose the material: Frank Retes, a respected reptile enthusiast and creator of the concept, recommends using plywood sheets instead of stone due to safety concerns. Stone stacks can pose a risk of injury or crushing for the reptiles. If you do opt for stones, try to get flat stone slates and make sure they are secured tightly.
- Cut the material: Measure and cut the plywood or other chosen material into rectangular pieces. The size and thickness of the layers can vary depending on your preference and the size of your reptile.
- Create angled layers: To maximize the available space and create tight crevices for the lizards to wedge into, angle each layer slightly. This helps create graduated temperature zones and enhances the hiding experience for the reptiles.
- Secure the stack: Connect the layers together using screws, brackets, or a strong adhesive (e.g. liquid nails). Ensure the stack is stable and won’t collapse. You can also anchor the stack to the enclosure’s floor to prevent it from shifting or falling.
- Add finishing touches: If desired, you can paint or weather the stack to make it look more natural. However, ensure the paint is non-toxic and safe for reptiles.
- Check the temperature at different levels: consider investing in multiple thermometers and hygrometers to keep an eye of both temperature and humidity in different areas of your enclosure.
Benefits and Considerations
Retes stacks provide several benefits for reptiles in terms of environmental enrichment: they offer a sense of security, mimic natural hiding spots, and create a range of temperature gradients. The layered design allows lizards to choose their preferred microclimate, promoting thermoregulation and overall well-being.
When building a Retes stack, consider the size and species of your reptile. Ackie monitors, for instance, prefer narrower spaces, so you might want to create gaps that allow them to squeeze in comfortably. Additionally, ensure the stack is securely anchored to prevent accidental collapse.
Remember, the goal is to create a safe and comfortable environment for your reptile. So, always prioritize the well-being and specific needs of your pet when constructing a Retes stack.

Magtara Ledge Hideout Rainforest Series
The Magtara Ledge Hideout Rainforest Series serves as a valid alternative to a reptile stack, particularly for smaller pet lizards such as bearded dragons. Its naturalistic design and secure interior provide an appealing and safe environment for these reptiles to hide and bask comfortably.

PetsWithScales.com is an informational website about big lizard pet care. We collect and provide information from different sources across the web on how to keep and care for reptiles as pets. The species we mainly deal with are tegus, monitor lizards, skinks and geckos. Our aim is to provide high quality information to help pet owners make better, more informed decisions about their animal’s diets, health and life.