Make a Fake Rock Cave/basking Spot for a Reptile Cage.




Introduction: Make a Fake Rock Cave/basking Spot for a Reptile Cage.

Here I'll show you how to make a fake rock cave/basking spot for your reptile cage. This is one I've made for my Bearded Dragon, Viggo.

Step 1: Design!

This is my original design I made months ago. The design has changed since then, but this illustrates the basic concept of what I wanted to make. A large cave, with a door allowing access to it from the outside, a basking spot above, and a ramp going up. PLAN AHEAD. I can't stress this enough. It will make things much easier for you. I've used Google SketchUp to render this 3-D model. Google SketchUp is a great FREE architectural 3-D design program. I'd consider this (or a similar program which may not be free) to be an essential tool for any craftsman/designer/builder. You can download the program here,
Google SketchUp Download

Step 2: Gather Materials and Tools.

Styrofoam ~ Free (This is trash, you can find it for free. It's used to pack all sorts of things. Try going to the back of an electronics store and asking if they've got any you can save from the landfills. I used a broken styrofoam cooler and some odd packing bits.)
Grout mix ~ $8.98 (I got a carton of Sanded grout mix in HEMP color. The sanded leaves a rougher texture than unsanded. The hemp is a kinda dark gray color that already looks like rock. It gives a nice dark base color and could be used without coloration if you want)
Cement Color ~ $4.96 (I used Terra Cotta. Mixed with the Hemp grout it gave a nice red rock color. This is a liquid color mix. You can also use powdered grout color mix. It's about a buck cheaper, but they were out of the color I wanted.)
Great Stuff Expanding Foam Insulator ~ $5.00 (Trust me, this stuff will make things much easier and is well worth it)
Water ~ (To mix the grout)
Water Based Polycrylic Satin Sealer (Go for Satin, not as shiny as gloss and gives a more natural look. You'll need enough for 3 coats. A small can will probably suffice. )

Knives and hand saws (to cut styrofoam and shape your cave)
Hot Glue Gun and glue sticks (works great for gluing pieces together and it's safe. DO NOT USE SUPERGLUE. Superglue, or other such chemical glues will melt/eat through styrofoam and give of toxic fumes)
Bucket (For mixing grout in)
2 Cheap Bristle Paint brushes (One for applying grout, one for sealer)

Step 3: Start Building!

The best advice I can give you here is to actually work inside your viv. This helps you make sure it will fit, as well as gives you an idea of proportions. You wouldn't want to accidentally make it too large. Remember to leave some extra room around the edges. You don't want it to be a tight fit now because you still have to grout it.

Start with a real rough cut, just laying things out. Don't glue anything down yet. It also helps if you can draw on the floors and wall of the viv to give yourself reference points for shape. If you don't actually want to mark your floor, lay down some newspaper you can draw on)

Get your basic shape together. Don't worry about leaving holes and don't do any detail carving yet.

Step 4: Glue

In order to get everything back the way you have it now, it really helps if you draw marks and lines onto your shape. Trace the outline of a piece onto the piece below it. Trace the bottom footprint onto the bottom of your viv or newspaper. Take off each layer and start gluing things down working from the bottom up (don't glue it to the floor!)

Step 5: Expanding Foam!

This stuff is truly great. I guess that's why they call it "GREAT STUFF"
Spray it in to fill in all those little holes and gaps.
Use a little more in places you want it to build up.
Leave it to expand and dry overnight.

Step 6: CARVING!

Pull out your knife and saw and go to town! Time to get creative and let your artistic side show. What you're carving now will be the shape of the final piece. Remember, don't go into too fine detail. The layers of grout will fill in a lot of the small stuff completely. If you want it to show up, cut it deeper!

Step 7: Grout!

Ok now, time make this look like a rock, and not a big chunk of foam.
Mix your grout. Don't mix it all at once. Leftovers will dry out while you're waiting between coats. Try using about 1/4 of your grout per coat. I don't really have a set measurement for water, but you want it to be kinda thin and soupy. It will brush on easier that way. If you're using coloration, this would be the time to mix it in.
Once you've got your soupy grout, start brushing it on.
Make sure you get in all the cracks and crevasses, including the bottom.

Let it dry overnight between coats.

Apply 3 coats! This will ensure everything is covered and it will be nice and strong.

Step 8: Paint!

I didn't paint mine, just used the cement color, but if you're gonna do that, now would be the time. Acrylic works best I hear.

Step 9: Seal It.

This is a very important step. Use a safe, low fume sealer such as Water Based Polycrylic sealer if possible. Shellac also works well but will leave it shiny. I actually ran out of polycrylic so I used shellac inside the cave and on the bottom where it wouldn't be seen.
Use your other brush and apply 3 coats of sealant, once again, making sure to get into every crack and crevasse. Sorry, no pictures here, cause there's not much to see while sealing. Once you've finished, let it air out for a few days, preferably with a fan blowing on it.

Step 10: Enjoy!

Well, this step isn't so much for you as it is for your dragon, but hey, you can still sit back and enjoy looking at your handiwork.

2 People Made This Project!


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163 Discussions


Question 5 days ago

Just happened upon your "rock". This question has probably been answered....what is the name of the grout you are using? And the sealer that you ran out of....was it matte? What is the brand of that also. This is amazing and I have loads of styrofoam.....

3 more answers

It's now been over 10 years since I made and posted this. Unfortunately, I don't remember any specifics that are not already in the post. I'm sorry to say I can't really offer any help. Best of luck.

No problem...totally understandable. Thanks for responding. Is it all still holding up after 10 years???

I can only say it held up for the 3 years I had it. At that point I moved and had to give my dragon and setup away. I can't say how long it lasted after that.

If anyone likes my terrarium, I made the rocks from 1 sollid peace of foam , carved everything out and coverd it with epoxy mixed with sand.
Then airbrushed it and and the background is just a nice air-picture covered with glass ...

2 replies

I just want you to know that I am in the process of making this and it is coming out fantastic! I will post photos soon.

Nice idea! and all the things are safe for pets I'm assuming?

i have a 2 mos old leopard gecko. i want t make a hiding cavern all along the back of the tank. just so it's one piece. but long enough to have a hiding spot in the hot spot and cool spot. have you done something like that?

this is so unique i love the way you made this product

Magnum kids- I have a question for you about your amazing rock installation. I hope you're still active on this site....

Hi Magnumkai , your cages are beautiful do you have a step by step instructions on how to do this ?



I made a fake rock but having issues. Its cracking. It took a few weeks to make. I thought it was ok but now that its been in the tank the whole under side is cracking. Im going to have to replace it now but should i be worried about fumes....

How many gallons is your tank ????

hey man awesome job just wondering if this is water proof i want to make a water fall for my red tail boa out of the same stuff

2 replies

making an aztec temple for my redtail it works well, and if you use the clear silicon (pasti dip) it will waterproof it. (using that ontop of the joint compound because i want to seal down the moss im putting on mine so my snake doesnt pull it off :) )

Do you have an instruct able on it? Sounds cool! :)

would this be hard enough so that the lizard isn't tearing at it and able to eat the pieces?