Why Do Japanese Roofs Have Rocks

I assume you re not talking about rocks meaning boulders but rather the layer of small stones you see not just on gas stations but on many flat roofs.

Why do japanese roofs have rocks.

I ve noticed in anime series such as inuyasha and other edo feudal era tales that the common homes in japanese villages had rocks and stones spaced out on their roofs. It aided in keeping the house sturdy in the face of earthquakes and wind. In the japanese feudal era placing rocks on the roof was a tool in building houses. Sliding doors were used in place of walls allowing the internal configuration of a space to be customized for different occasions people usually sat on cushions or otherwise on the floor traditionally.

Why did the edo japanese villages put stones and rocks on their roofs. Magazine and roofing southwest although single ply roofs inherently have sun protective qualities ballast provides an extra layer of protection from uv rays. The gravel in a ballasted roof helps absorb heat preventing the sun from heating the roof materials below and making the roof more energy efficient. I think some people do it because they like the look.

My question is why do gas stations sometimes have rocks on the roof. Ideally the stones are river gravel which has smooth edges and won t cut. Although there are a number of differences among the roofs seen in different areas of japan they all have one thing in common. The roof is the part of the house most affected by rain wind snow sunlight and other natural conditions.

Reminded me of haiti where they use rocks of any type to hold the tin sheets on through a storm. They are sloped instead of flat allowing rainwater to flow off easily. Chairs and high tables were not. Unfortunatly it doesn t do much to protect against demon attacks.