What are those things on the roof?

Those little spikes are there to break up sheets of ice and snow that fall off the roof. If the ice comes down in large, heavy, wet sheets, they can cause lots of property damage and hurt people.

There are lots of videos of snow falling off roof surfaces with people scrambling and cars getting damaged.

It is less destructive if it gets broken up on the way down. The spikes break up the snow-ice sheet as it falls past them. 

Here are all the different names that these spikes have acquired over the years:

• Snow Cleats

• Snow Stops

• Snow Breaks

• Snow Blocks

• Snow Catchers

• Gutter Guards

This post has a more detailed breakdown of the reasoning behind each name.

While I am on the topic of snow coming off the roof, here’s another joy of urban living.

Roof surfaces are mostly asphalt. But, in this area, we still see a lot of slate roof surfaces. If your neighbor has a slate roof and your houses are close together, you may hear a scary sound. When the snow falls off, it rubs against the slate shingles and it sounds like a mountain avalanche.