cube cages and coroplast

I have been researching getting a house rabbit for a couple of months. I have been in contact with a rescue place and my application was approved. I just needed to send pictures of my habitat. I researched housing and decided to make a cube cage and use coroplast on the outside. I completed the cage and was told by the rescue place that these cages were not safe because the bunnies will chew up the coroplast and the plastic ties. She said that using the plastic ties makes them not sturdy as well which is dangerous. She said I should look into an x pen. I see these cages all over and actually got the design and ideas from brighteyesanctuary.org. I have spent a lot of time and money. When I called her she actually asked if I was the lady with the crazy cage. I told her I had researched cages for awhile and got the idea from a rescue place. She said that the internet has a lot of stuff on it that is not true. I want to make it safe, but I need suggestions. I made the cage 2x4 and the coroplast is outside the cage. I used the plastic ties and tightened them and then cut off the extra part. I have two shelves that are around 14 inches wide by 28 inches long. I used the dowels and secured them with ties. I then put wood over the dowels and put the square linoleum tiles down. I will cover that with fleece. I used ramps and put steps on them. Help!

Cube cages are actually a standard in the world of house rabbits. You can see plenty of examples here on this forum of these cages. People here who have kept rabbits for decades have used these cages. It sounds like perhaps this is a new rescue?? with volunteers that have limited experience??

Perhaps they ought to have a visit to this forum.

That said, part of their concerns are somewhat warranted, however they are also mistaken on a couple points. I'll try to review below.

The zip ties are actually recommended to hold the grids together. That is what makes the cage sturdy. However, there are some small, thin zip ties that break easily. These would be a problem. But the thicker ones work just fine. I can't tell how thick/strong are the ties you've used.

Coroplast may be chewed by some rabbits. I don't like to use it because it is quite slippery. But others have used it and covered it. But, as you've stated, the edges of the coroplast on your cage are on the outside -- so it can't be chewed. The way you have used the coroplast is fine.

I would point out, however, that the ramps in your cage are far too steep. They look more like slides than ramps. You would be better off extending the top shelf across so that it is double its current size. That would allow the middle shelf to act as an easy hopping ledge between the floor and the top shelf. Rabbits can easily hop up one grid provided the flooring is not slick.If you did that, there would be no need for ramps at all. Ramps just waste space anyway.

The cage you show is actually 2 grids by 3 grids but you stated it was 2 x 4. It would be better if it were 4 grids wide rather than just 3.

Fleece placed on the floor or the shelves will need to be secured somehow or it will just be dug up and slid around.

The person you spoke with is, of course, correct that there is a lot of wrong information available on the internet. However, using cube cages is absolutely an accepted standard and is even encouraged by many rabbit rescues and reputable rabbit care sites.

Binkybunny.com has a page that shows very good cages for rabbits - including the cube cages. I suggest you forward the following link to the rescue for reference.
http://binkybunny.com/BUNNYINFO/GreatHabitats/tabid/229/Default.aspx

The binky bunny site has a great reputation and I can't imagine a bunny rescue not being aware of them. Nevertheless, they should be put at ease about cube cages once they view the site.

You may also be inspired looking at some of the ideas on there.

Yes, that kind of cage is pretty standard in France too. I use one when I have to quarantine a new bunny as you can build it and then take it apart and use the cubes for something else pretty easily. Yes, rabbits will probably eat a bit of coroplast, the same way they will nibble on the plastic of a regular cage (I would add that many cages have some on the bars and that the rabbits will eat it all the same) and it's unlikely to harm them.
I would be more concerned about the plastic ties, not really because the rabbit could hurt himself but because if he eats them, the cage will fall apart (rabbits can eat things VERY quickly and kinda supple plastic things are gobbled up before you can say 'bunny') ^^. My cubes came with some hard plastic black things to hold them together, like those :
http://www.catsandco.net/habitat-du-lapin-les-cubes-modulables/
Maybe you can just reinforce the structure with some wire, making sure no sharp end is on the inside so the rabbit can't hurt himself or with those small clips (I used those as well with my youngest rabbit, as Tybalt liked to climb on the walls of his pen ^^'). Like here :

The plastic connectors that come with grids are not as secure as zip ties (which is why zip ties are used for rabbit cages). A determined rabbit can break through a cage held with those round connectors that come with grids.

We've seen this a few times here on RO where people had issues with their rabbit charging the walls and the connectors popping loose. The colored clips that Aki has used look like reinforcement between corners. That's a good idea.

If the zip ties are pulled tight, bunny won't be able to get their teeth on them.

The connectors can be used for guinea pig cages.