Vests are a great option for the workplace. The lack of sleeve means they'll fit comfortably under your suit jacket or blazer without restricting movement, yet if the heater kicks into overdrive in the office, you don't risk overheating.
Cardigans can be a little bit scary, I know. But if you're after a hipster/preppy look, the man-cardy (or mardy, as they're called in our house) is your answer. Buttoned up for the office or undone for a more casual look, you can just chuck on your mardy and head out the door at a moment's notice.
But if the mardy is too risky for you, you can always fall back on the old favourite - a hoodie. Hoodies made of sweatshirting should stay distinctly in the realm of skater/surfer kids and students. But a knit hoodie? Now that's a casual bandwagon I can get on. In fact, several years ago my husband had a lambswool hoodie from Mandatory in Wellington that he wore every day for three years. Eventually it wore so thin it wasn't warm at all, but he continued wearing it until the sleeves wore right through to nothing. It was a great purchase and a great comfort piece.
There are a few keys to making your knitwear last as long as my hubby's hoodie.
The first is content - if it's 100 per cent merino or lambswool, it will last longer than polyester. I realise wool can be expensive, so just buy the highest wool content you can afford. Having said that, wool has come down in price significantly in recent years. Hallensteins have nice wool-blend knits for $39.99.
The other key is to make sure you look after your knits properly. Read the care label. If it says handwash only in warm water, then only handwash it in warm water. Some are okay in the washing machine on a delicates/wool wash, but if you're not sure, handwash for safety's sake. It'll prolong the life of your garment. And for goodness sake, don't throw your wool knits in the dryer! Finally, dry them flat on a clothes horse and store them folded. Coat hangers will stretch the shoulders out in unnatural ways.