1. Can i keep a worm bin outdoors in zone 6? The worm bin would be a rubber maid storage bin with holes drilled at the bottom and along the sides and raised from the balcony floor with bricks to allow for any drainage and air circulation. Indoor space is limited. Would I need to provide insulation? An alternative construction for a worm bin would be to use root pouches as the worm bin and stick that in a rubbermaid storage bin. Holes would be drilled along the sides and lid of the storage bin. If you're not familiar with root pouch, they are pots made with recycled fibers. You can google "Root Pouch" to find out more info. Would the worms eat the "root pouch"?

2. I understand that bedding is very important. i have read that moistened newspaper is a popular bedding. I was wondering if i would be able to mix in used hamster bedding, which would include hamster droppings and sand. Below is a link of the bedding material and dust bath for your reference:
http://www.kaytee.com/products/softsorbent.php
http://www.kaytee.com/products/chinchilla-dust-bath.php

I look forward to your advice!

2. i would assume you can use hamster bedding. i don't think hamster eat meat so i don't think it would be horrible. you do not want to put in animal droppings if they eat meat that is the rule. other then that yes you can most likely it will heat up due to the poop. sand is fine i would not put a lot of sand though. worms need sand/grit for digestion people say. i put in a little egg shell from time to time and i also see people put in sand/rock dust. some don't put anything at all and they have no problems. as for the dust bath im not sure about that you might want to check the ingredients are safe for the worms.it says it is all natural so i assume it's safe. for my bedding i use newspaper, old napkins, cardboard, used bird seeds, old dead plants, leaves. i use red worms/red wigglers and i live in Hawaii so it's hot they seem to be doing great.

Bedding
A reason why newspapers are popular choice is not because it's great for worms. It's because it's just there. You can use others if you have free access to them.

Dust Bath
I looked into dust bath. It's likely to be a mineral (rock) powder which won't harm the worms. They possibly benefit from it for their gizzards. In this case, don't bother adding any other fine powders (eggshells, sands, etc) with a purpose for their gizzards. (Worms can survive without powders apparently so I assume they collect gizzard stones from food and beddings anyways, so don't give them excessive amount of dust bath)

Soft Granule Blend
It's "sanitized to aid in bacteria control." I'm not sure exactly how they sanitized it or did they leave traces of chemicals in bedding that can harm the worms. The worms eat bacteria and fungi that eats food, so you can see the problem. I cannot say if it's great or bad bedding for worms. If they didn't mention it, I would think it's fine for worms when moistened.

Hamster Droppings
It's safe for worms. It's food for them so it's good!

My Worm Bin
We're alike. I have an urban balcony garden. Initially I kept my bin outside for late summer to early fall. When it got cold, I brought my bin inside because I prefer them to be active, not slow so they can continue to convert food into vermicompost. Right now, my worm bin is inside my utility closet. Are you sure you don't have a space for it somewhere? Bringing it indoors is easier than going through hassles to add insulation and trying to keep your worms warm.

And thanks for the link about temperature differences - @aindra

We live in the NYC area so it can get cold. I'm also concerned about the vermicompost attracting roaches, which is why I would prefer to keep it on the balcony.

I looked up how to build an indoor worm bin and this link is very helpful. It has instructions on how to build your own as well as FAQ on maintenance.
http://www.nyc.gov/html/nycwasteless/downloads/pdf/materials/wormbin.p df

On a similar note; What about keeping worms in a container of dirt? I have found a worm while digging out annuals from a container. I don't know if the worm is still there. I had found another worm early in the year. It came in a strawberry plant I ordered. I planted the whole thing (including worm) in a strawberry planter, the planter with multiple pockets. I have read that keeping a worms in a container with growing plants isn't a good idea but I haven't noticed the plants failing. Then again, I don't know if the worm is still in the planter or has crawled out. The worm was purplish.

2) Sand is not bedding. You should not put sand in the bin, except in very small amounts. Bedding is organic material that is high in carbon. Sand is not organic. Some people claim that putting a small amount of sand in the bin helps worms digest their food. Others claim they see no difference with or without sand in the bin.

The soft granule blend might be OK for bedding. It is hard to tell. The best thing to do would be to get your bin established, then put a small amount in to see how the worms react to it.

I don't know what is in the dusting powder, so I can't say whether it can go in the bin.

If you are asking about keeping worms in a container of dirt, then you do not understand enough about worm composting to be starting a bin any time soon. The short answer is that 1) Dirt is not organic, and therefore will not compost and, 2) composting worms will not live in dirt. Composting worms live in and eat organic material. There are other varieties of worms that live in dirt, but they will not survive in a worm composting bin.

as for roaches it is fine to have roaches in the bin. i keep my bin without a lid and it has 1 or 2 roaches at the most. the main problem i have is fruit flies thats because i didn't really cover it at first until 2 days ago but their are methods to get rid of fruit flies easily.

you can also screen your lid to avoid roaches and worms crawling out. i found with my bin keeping the lid off was much better to allow more oxygen the only problem i have is the bedding at the surface keeps drying out daily. but with a lid the worms used to alays crawl on my walls trying to escape lack of oxygen.

it is up to you. the worms can only handle so much cold not to mention the temps inside the bin is colder then outside due to the content being wet. so if you have a compost/soil thermometer check the bin temps. i highly recommend insulating the bin the warmer it is the more active they are you just don't want it too hot to the point they end up dead

Hey, let's run outside and measure my bins! ... Here we go: the air temperature around them is just below 60F today, the outside surface of the bins measures 60F, but the center of the bins, inside, is a toasty 75F.

Re other critters (a) I don't think cockroaches are a good idea! but (b) fruit flies and other little flies, once established, can be extremely hard to get rid of. There are some highly experienced folks on this forum who successfully keep bins indoors, but if you have the option I'd go outside, and invest $10 in a little soil thermometer to monitor temperatures.

Cold extremes: You might consider an appliance box over the bin as a windbreak, and/or or some kind of insulation, and some folks have reported using a seedling mat to provide a little extra heat input. But I doubt NYC has the *sustained* cold temperatures to freeze a bin. The worms and other biological processes will slow down in a relatively cold bin and thus process less food, though.

Heat extremes: These are more likely to be a problem for you, especially if your balcony gets a lot of sun. One hot afternoon can kill the worms en masse, and dead worms smell horrible. It's those July days in the high 90s that I would plan against. If you search you'll find more on hot weather measures.

i didn't think it was okay to have roaches in the bin and certainly not fruit flies.

I have been thinking about how best to go about keeping a VC and I think I might start out with a small bin and see how I and the worms do. I may be able to keep a small bin indoors. I definitely prefer to keep the bins outdoors on the balcony. I like your suggestion of putting an appliance box over the bin as a windbreaker.

On a separate note, in my previous post, I mentioned that one of my container that is filled with soil (I'm not planting anything in this container) has an earthworm in it. I've put a small scoop of hamster bedding in the dirt along with torn up comfrey leaves. I think the earthworm has consumed most of it because when I went digging around in the dirt, i don't see much of the bedding and comfrey leaves. Or could that just be the natural course of decomposition? In any case, I put in another small scoop of used hamster bedding and buried it under dirt. Will see what happens next week.

Anybody have any experience on this? I know it's not vermicomposting but if the earthworm is still in the container of dirt and consumed the used bedding and comfrey leaves I buried last week then the castings is enriching the soil? It's actually potting mix, not soil or dirt I dug up.