Tired of the Chewing..

I would argue that he doesn't "know what he did wrong", only that he knows you are upset with him, and therefore he cowers.
It is great that you take him on walks (long ones! ) and that he gets play time outside with the family, and has toys of his own. But, I will mention a few things that might help. Pardon if I make any assumptions that don't apply--not every detail can be given in a post, and something may have been left out that might make a difference.

1) Regardless of locks or ability to close doors, get him a crate and use it. A crate is not a place to go when he is naughty (neither should the bathroom be). It is a place to confine him to keep him safe and out of trouble, when he cannot be directly supervised. Since he hasn't learned how to behave while UNsupervised.
2) The only time you should punish/correct him is when you catch him doing something IN THE ACT of whatever it is. You catch him on your bed with mattress in his mouth. Or you catch him mid-bite with your sofa pillows. THEN you screech or whatever.... Not 30 minutes later when you come home and find it.
3) Having toys of his own isn't enough. He wants/needs you to actively engage with him with the toys. Toys alone are boring for many dogs. Ours will completely ignore hers (with the occasional exception of a tennis ball that she rolls around and drops to make it bounce) unless there is a person to play with them WITH her.

Other than those things, it sounds like you are doing a fairly good job of doing the right things. But, 1 year old IS still puppyhood. I don't think the chewing is teething anymore, but puppyhood and still needing proper training to understand the rules of the pack he lives in. Our dog is not allowed on ANY furniture, and that has always been the case. We crate trained her from day one. And she is a lovely addition in our house because she was never allowed to have the "run of the house" until she demonstrated enough understanding and self-control to follow the rules of our household. Don't allow them to fail.
You must constantly supervise your dog, until he has learned what is and isn't acceptable behavior. The only way he will learn something is unacceptable is if you correct him IN THE ACT when he does something wrong. And the only way to consistently do that is to BE RIGHT THERE when he is out. It is impossible to do that if he has free access to the home unsupervised.

Lack of doors or latches or whatever doesn't matter. It is the roaming around the house that matters. You don't need doors or latches or baby-gates if you have an appropriate crate.

Good luck. It is not a lost cause. And it sounds like you love him very much and are willing to go the "extra mile" (even though it isn't really extra, and in my opinion, should be considered just part of properly training a dog).

Read up on "crate training" so that you understand what it is, AND what it isn't. It isn't intended for use as punishment, at all.

ETA:
Many people only think of crate training as it relates to house breaking (pooping/peeing in the house issues), but that is NOT all it helps with.

http://www.inch.com/~dogs/cratetraining.html
http://www.dogbreedinfo.com/cratetraining.htm
http://dogs.about.com/od/dogtraining/a/crate_training.htm

keep him crated you aren't home. Go out and get one.
give him toys that challenge him like these http://www.petsmart.com/product/index.jsp?productId=36410... or this http://www.petsmart.com/product/index.jsp?productId=12811...
Get him some "white bones". They are real bones ( cow femurs) some come filled with stuff some are empty. I find them at Petco.
He can't comprehend that it's wrong unless you catch him in the act. After it doesn't matter , after he won't know what he's done he only knows your mad.
My dogs went through the chewing thing they grew out of it. They are a year and a half old. But also remember as well bigger dogs mature slower than smaller dogs. They are "puppies" much longer.

put a dog gate in your bedroom door to prevent him from going through. humans can easily open it or step over it.

the only other option is to never ever let the dog out of your sight and to crate him when you are not home.

he may well be mourning the loss of the other dog. talk to your vet also, s/he may have some suggestions.

I believe a combination of things is causing this behavior. One issue is that he is a puppy and hasn't quite learned his manners. Like someone else said...he knows he was naughty but isn't sure what he did wrong. A bit confused I guess. To add to that he is definately showing signs of separation anxiety or mourning. We had a dog that was very destructive until she had a friend (our second dog). Chances are your dog is acting out because it is sad & confused and doesn't know how to commicate well. The loss of your husky just turned a smaller chewing problem into a much bigger problem. My dogs have always shown the stages of grief after the loss of a buddy just like people. If possible maybe a new buddy would be good. I have found that pairing a puppy with an older (3-5 yr old) dog can be great because they can play together and wear each other out but you only have one dog that needs extra training. Check petfinder.com or humane societies for great dogs. A new dog and some extra training should help. BTW I am so sorry for the loss of your husky. I had a 16 yr old husky/German Shep that was a great buddy to several younger dogs. i think she was like a foster parent to the younger dogs. She was our destructive dog when we first got her as a pup. Her behavior changed overnight after we got her first buddy and she was a dependable wonderful dog after that. Good luck!

Hi! Could it be separation anxiety? My perfectly angelic dog turned into a wild animal when we left him home alone. Oh, and he destroyed three crates before we gave up. We ended up with a soft muzzle that allowed him to drink and nibble his food but left him unable to chew. We almost always came home to very cushion and pillow on the floor though. He wasn't allowed on the furniture or bed and never went on them when we were home. Good luck!

Sounds like anxiety from the loss of his pack-mate. I would say definitely get a doggy gate/baby gate for your bedroom, and get him a real crate to stay in when you are not home (crates are not a punishment, they are like a dog's "safe place" or den, too) Buy a Dog Training Problem solving book, just search on Dog training, or dog problems on Amazon: http://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias...

Petsmart has a spray, "Bitter Apple" I think, that tastes nasty so they won't chew things. Make a point to play WITH him with his chewy toys, and really praise him when he chews what he is supposed to chew.