Our old house in New England has a steep pitched metal roof and no gutters. Our front door is right under a roof valley, so it is unusable on rainy days and all of winter. The water running down the valley has rotted out our building sill, and we have to get it replaced. I don’t want the same thing to happen to the new sill! Installing gutters is not currently an option because the winter snow avalanches would just rip them away. I have read about snow guards, but have never seen any in real life. How well do they work, are they hard to install, will they work when 18” of snow falls on the roof? Will the snow guards slow down the avalanches enough to keep gutters in place? Alternatively, should we just build a porch to divert precipitation further from the foundation? Any advice is welcome!
You need to hire a drainage specialist. you need gutters designed for the snow load of your roof and you need proper drainage to take it away from the house. If you already have rotting sills your in trouble. It's going to be much more expensive to ignore the drainage than to have it done.