What are any good reasons to build steeper than 4/12?
6/12 is somewhat ok but one loose shingle and forget it. Don't get me wrong though, a loose shingle on a 4/12 is still very unsafe, all it takes is for the few nails to be oversunk just a tad, which you wouldn't see, and it's like putting one foot and all your weight on a piece of cardboard that can shred downward through the few oversunk nails holding it - but the steeper the roof the more likely this can happen. That's all beside the point of slippery conditions caused by old asphalt granules on the roof, moss, etc etc. But 4/12 the least steep is like a night and day difference. You can barely put tools on a 6/12 without needing a tied off bucket or something either. Just walking on a 6 or 9/12 is dangerous.
The 'reason' or benefit for a steep roof is that it sheds water quicker and is less prone to wind lifting shingles BUT it's only a minor difference compared to a 4/12. 4/12 will last just about as long AND any time the home owner needs something done on the roof, gutters cleaned, attic fan etc, etc, even a frisbee stuck on the roof they have to call a roofer willing to go on that steep roof. The cost of that negates the short amount of time a steeper roof will outlast a 4/12. There are 4/12 3-tab roofs from 60+ years ago still in great shape.
Is it simply supposed to look nicer? That's an internet forum answer I'm thinking I'll hear but I beg to differ it's just opinion.
6/12 is somewhat ok but one loose shingle and forget it. Don't get me wrong though, a loose shingle on a 4/12 is still very unsafe, all it takes is for the few nails to be oversunk just a tad, which you wouldn't see, and it's like putting one foot and all your weight on a piece of cardboard that can shred downward through the few oversunk nails holding it - but the steeper the roof the more likely this can happen. That's all beside the point of slippery conditions caused by old asphalt granules on the roof, moss, etc etc. But 4/12 the least steep is like a night and day difference. You can barely put tools on a 6/12 without needing a tied off bucket or something either. Just walking on a 6 or 9/12 is dangerous.
The 'reason' or benefit for a steep roof is that it sheds water quicker and is less prone to wind lifting shingles BUT it's only a minor difference compared to a 4/12. 4/12 will last just about as long AND any time the home owner needs something done on the roof, gutters cleaned, attic fan etc, etc, even a frisbee stuck on the roof they have to call a roofer willing to go on that steep roof. The cost of that negates the short amount of time a steeper roof will outlast a 4/12. There are 4/12 3-tab roofs from 60+ years ago still in great shape.
Is it simply supposed to look nicer? That's an internet forum answer I'm thinking I'll hear but I beg to differ it's just opinion.