Flat roof mounting system for solar panels are mainly divided into two categories. One is ballasted mounting type which has no any damage to roof. The other is using expansion bolts to fix the feet of structure to the roof, the expansion is drove into the roof, so this type has damage to flat roof.

1. Damaged type flat roof solar mounting solution. We can adopt this type of flat roof solar mounting structure if the flat rooftop is strong enough. The structure on roof is similar with structures on ground. Material can be both aluminum and steel. Weight of aluminum material structure is lighter compared with steel steel. So aluminum is more ideal for such type of flat roof mountings. But cost of aluminum material is more expensive than that of steel. There is a risk of roof water seepage with this PV mounting method. So we have to waterproof the roof.

2.Ballasted type of flat roof solar mounting structure. Solar panel ballast mount on flat roof is very popular now, especially for the old buildings. Because roof of such old buildings is weak , it can’t suffer from any damage on it. So driving bolts into the rooftop isn’t a good solution. Ballasted PV mounting structure isn’t penetrate the roof, it is a friendly mounting way to old building rooftop. And more material of this mounting structure is normal aluminum,which is lighter , so it is good to weak roof. Ballast mounting system also has an advantage of easy installation, which could save a lot installation cost.

There is a special ballasted type. Normally we put ballasted stone or block on the bottom rail of structure to resist the wind. But we also can fix the feet of structure to the ballasted block by expansion bolt, the blocks are put on roof. We can also embed the anchor in the cement block when producing the concrete block. And then fix the structure to the anchor by nut.

Corigy also do good in flat roof solar mounting systems. If you have flat roof solar projects , welcome to send inquiry to us. Thank you.

Ballasted vs. Bolted Flat Roof Solar Mounts – Which to Choose?

Choosing a flat roof solar racking system? Learn the pros and cons of ballasted and penetration mounts, plus cost-saving tips for old buildings.