Should workplaces relax dress codes for the hot weather?

What do you think? I hated how much I always had to dress up even if it was like 100 degrees. Though admittedly, I just stored shoes and jackets and such at work when we had heat waves. But this brief article brings up a good point—relaxed dress codes might confer some benefits:

Turns out that some businesses are noticing that what we wear can cause pain to our planet. Relaxed summer wardrobes are a good start to easing the pain: the fewer layers you're wearing, the less air conditioning you need to be comfortable. Bring on the polo shirts!

Thoughts? Do you work in a place with a dress code? How do you manage it? (get a couple basic dresses minimally) Should it be relaxed during heat waves? Should there be any accommodations?