Reptile & Amphibian Forums

Thanks to everyone who answered my last post. I still am unsure on one thing, Which is better PVCX or HDPE. I am not too worried about weight as long as a 4x2 is movable with one person. I am worried most about sagging, durability, and cleaning.

I could buy 1 cage each from the two people I am looking at and then decide which I like. So what do you guys think? Again thanks in advance for any advise.

n/p

It is a big extra. But I would say that sagging is the most important. If I bought a stack of cages and 3 years later the tops were sagging I would be highly @#!$ off.

Intesting you should ask. Here in the UK we have a shortage of manufactures who produce plastic cages. So... I now am in the process of producing plastic cages for the herp maket in the UK. I looked into HDPE and Polypropylene, not PVCX. (Although I know The USA and the UK use diffrent terminology - could PVCX be the same as Polypropylene?)Anyhow bottom line as far as HDPE and Polyprop is concerned . Both are safe for herps , but - HDPE tends to sag more. Polyprop seems to be stonger, less flexible, and a self-extinguishing material. I am no expert on this subject, I just gleaned it all through sufing - hope this helps.
Alan

PVCX is expanded Polyvinyl chloride so it's not the same.

Sagging is a big issue so if HDPE sags then I am going nowhere near it.

Saggin will be a issue in both materials if not properly placed , By this if you set things on top of your cages then they will need to have the same footprint ( same area to sit on the cage under items) so if its a 2x4 cage then you would not want to put a 3x2x1 cage on the top of the cage , you dont wanna put any fish tanks all those extra reptiles mags etcetc on the cage.

Now having said that using a 3/4 peice of plywood will span the walls ( foot print of the cage and disperse the weigh more evenly) across the top of the cage to keep sagging from being a issue. Single door cages can sag due to the long span with HEAVY snakes in it and heavy substrates in the cage but this is mainly due to the span across the front of a 4 ft cage being roughlt 44" there will be some deflection when weights piled in them( i compensate this by having a larger gap in the center of the door over the center) double doors would illiminate this chance from occuring. From using both materials in caging yes PVCX is self extinguishing and HDPE, HDPP have some that are aswell but the key here is as long as there is a source of ignition then there will be FIRE steel burns when hot enough as will any plastic with a flame to it long enough so the myths of self extinguishing are true but can be deceiving to a "laymen"

Both have there quailities with use but the biggest one is abuse and weight the HDP weighs i think about 15lbs more then the PVC of similar sizes. Durability as Ed mentioned ya you can beat a HDPE cage with a hammer and only scratch them and not normally bust them but ... who beats there cages with hammers , HDPE CAN break and is not as easily repaired as PVCX materials are if a break / crack should occur with the PVCX you can repair them to almost unoticable most ofthe time , even if a chunk is broken out you can repair the cage yourself in less then 10 mins you cant make the same repair to HDPE that fast with out a thermal welder and some of the same material to weld it back together.

So yeah both have there plus's and minus's
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__The Revolution has begun ... www.junglehabitatsplastics.com_

signature file edited, contact an admin 6/12/06

OK the hammer thing was an example...LOL... but you can repair HDPE with a weld..

I was just typing about the whole fire resistant thing myself. Most cages have acyrilic doors and it burns vigorously! anyone who has seen the plexiglass brands protective film knows, it's stamped all over it!...LOL... Any fire is bad news my folks house burned down in 2000 and everthing that wasn't burnt was melted into a puddle on the floor including metals.
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Ed Lilley, www.constrictorsnw.com
www.reptileinsider.com

If the Boaphile is reading this perhaps he would tell us a little more about his plastic? According to the Boaphile website here:
http://www.boaphileplastics.com/safety.html
he says: "... our cages and racks are built from a PVC type plastic. PVC is "self extinguishing". Self-Extinguishing! This means when you attempt to burn one of my cages or racks the material itself releases a gas that extinguishes the flame preventing the material from self-consuming. I have personally taken a torch to my plastic and burned it for a full minute. As soon as the torch is removed the plastic material is extinguished and ceases burning! That is correct. Our cages and racks can't burn without an external fuel source.."

In other words the plastic emits a gas that extinguishes the fire. You say everything burns but you are incorrect, some things don't, they put themselves out wherever it gets hot enough to burn. There are legal definitions of words like "flammable", "flame retardant", and "selfextingishing." It isn't meaningless. He held a torch to it for a minute and it still put itself out! I think what you are saying has no foundation.

Caden

you said " . . . From using both materials in caging yes PVCX is self extinguishing and HDPE, HDPP have some that are aswell but the key here is as long as there is a source of ignition then there will be FIRE steel burns when hot enough as will any plastic with a flame to it long enough so the myths of self extinguishing are true but can be deceiving to a "laymen" ..."

Author: Anonymous Date: 02/11/2005 12:12:45
Question
How do pvc and hdpe differ in their reaction to accidental domestic fires, particularly is their a differance in the smoke or toxins produced?

Author: Niall Rowan Date: 03/05/2006 18:31:49
Answer

A brief explanation is as follows...

PVC

pvc or polyvinylchloride is widely used in the domestic environment; in electric cables, in wall coverings and more recently in door and window frames. When subjected to a small ignition source it will usually burn but combustion will normally cease without the 'assistance' of more heat - usually in the form of impressed irradiance from a burning item such as a sofa. In other words even if ignited, it will usually stop burning without some extra heat.

[Cautionary note: Please do not use or accept the term 'self-extinguishing' which has sometimes previously been used in association with pvc. This term is now deprecated as it infers some degree of safety which is not justified].

This burning behaviour is as a result of the chlorine in the pvc. When pvc burns it forms hydrochloric acid gas and other halogenated compounds which are known and effective flame retardants. That's the good news.... The bad news is that hcl gas is an acid gas and is consequently a severe irritant to the respiratory system. It also is extremely corrosive to metals.

However, the irritancy is not usually fatal in that in most fires, death is normally caused by carbon monoxide poisoning. You get carbon monoxide when you burn just about anything and especially anything cellulosic. A pvc fire in a domestic environment is likely to damage electronic equipment which is particularly sensitve to halogen gases (hydrochloric acid gas, hydrogen bromide etc).

HDPE

HDPE or high density polyethylene is a different kettle of fish. Polyethylene is also widely used in the domestic environment, but not usually in furniture or wall linings. You can sometimes detect polyethylene easily as items made from it (plastic bags, chopping boards, table tops, wheelie bins etc) normally have a 'waxy' feel to them. HDPE burns less readily than PE, but as there are no halogens in HDPE, it will still generally burn more readily than pvc.

Put simply, HDPE and polyethylene are more flammable than pvc. Manufacturers can and do use inorganic fillers and other flame retardants to help improve the fire performance. As with pvc, it will be the carbon monoxide that kills you, not any particular combustion product of the HDPE.

Here's where I found this info.

http://www.warringtonfire.net/ListFAQs.asp?faq_id=67
Link

I have worked with all of the plastics mentioned. They all have their good and bad points. I have built cages out of them, and done plastic welding repairs on everthing from boats, and cars, to chairs.

Polypro- nice and glossy,cleans up easily, solid, good color choices,including semi transparent colors, but brittle, acidic fumes when welding and melting (burning). Costs more to use affecting the cost of the cages in the long run. Is plastic to plastic weldable. Supports flame acidy smell.

HDPE- glossy, solid, safe to use, cleans up easily, used for drinking water pipe and cutting boards and such. Good color chioces including semi transparent colors. Better workability than polypro (not brittle) Better impact resistance but will bend more easily than poly-pro. This plastic will bend before it will fracture. Is plasitc to plastic weldable. No off gasing when welding will support flame smells like candle wax. will support flame.

Both HDPE and poly-pro are a rigid high density plastic if heat bent and welded these plastics won't sag. A cage built of poly-pro or HDPE 1/4 inch thick, 4x2x1 weighs about 30 pounds.

PVCX- Most of the same properties of regular PVC except PVCX is a rigid expanded foam, both the top and bottom are closed cell but the inner core is an open celled foam. Safe to use, kind of a satin-mat finish, harder to clean, good color choices but all must be solid due to the foam nature of the product. very easy to work with bends quite easily, and is light weight A cage 1/4 inch thick 4x2x1 weighs about 22 pounds. Plastic is brittle will fracture if put under a stressfull load. You can not weld plastic to plastic with PVCX but you can with solid PVC. PVCX must be glued (chemicle welded) PVCX will not support flame but will puff up like a mashmellow and melt in the presence of fire or extreme heat.

Acrylic- you can make all kinds of beautiful clear things from this product. Finish is slick and clear. Makes great doors. Can not be plastic to plastic welded must be glued (chemicle welded) harder to bend. Burns vigorously.

The whole fire resistant thing realy doesn't help anyone, if they don't burn they will put off noxious fumes and melt, it's all plastic. If your cages were steel they wouldn't burn but you'd still be in bad shape with a fire (they call that an oven). Be more worried about not having a fire. Put a smoke detector in your snake room we all no there are lots of wires in there.

I have seen many types of plastic cages made, I'd have to say they are all quality in their own ways. I think it's impressive what people can make from plastic, and plastic sheet with enough thought and work. Pick what works best for you, and your animal in your situation.
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Ed Lilley, www.constrictorsnw.com
www.reptileinsider.com

If I was unsure as to which cages I'd prefer I would buy one of each.

That way I could check them both out up close and personal. I wouldn't have to rely on what others prefer, because I could put them both to the test and decide for myself.

I know it's going to be a bit more expensive, but for me it would be a better way to go. Besides you won't really be wasteing any money. You'd still be able to use the cage that wasn't your favorite. You'd just be buying the rest of the cages in the style/material you like best. You'd have one "odd ball" cage, but you would have made the most informed choice.