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Flat Roof Mounting Kit / Ballast

  • 22-06-2022 9:03pm
    Registered Users Posts: 118 ✭✭


    Quick question - I've just had panels installed on a flat roof with the Renusol kit.

    I was expecting a neat presentation - everything I've seen in the installation documents and in photos has shown paving slabs or concrete blocks used as ballast for the mounting rails.

    But in our case the roofer used these 8 foot concrete fencing posts with a twisted steel core, so the posts extend beyond the length of the panels and mount, and have ended up going dipping and rising in some places, warping the aluminium, and making the entire thing look a bit of a mess.

    The flat roof is super visible from our upstairs windows, so it sort of ruins the view.

    I'm going to speak to the Solar company asap, but just wanted to see what other people's experience may have been with flat roof mounting kits like this?



  • Registered Users Posts: 1,456 ✭✭✭Evd-Burner

    I did a DIY of this and used concrete blocks with speed porter. Not too happy with the end blocks showing and thinking of changing the ballast.

    there are lots of options, you just need the renusol report which your supplier should have prior to buying the mounts.

  • Registered Users Posts: 2,400 ✭✭✭bullit_dodger

    Renosol have a couple of ballast buckets too (if you can get your hands on one - good luck)

    CS + solar panel mounting system for flat roofs - Renusol EN

    Roof mountings are critically short. Critically. It wouldn't surprise me that some installers are having to "make do" with what they can.

  • Registered Users Posts: 2,215 ✭✭✭Citizen  Six

    That sounds terrible. Some people just don't think of the aesthetics of these things, and often they are just totally out of view.

  • Registered Users Posts: 118 ✭✭simpsimp

    Thanks for the feedback. We have managed to get 2.34kW on the flat roof, so that's the up-side!

    I'm talking with the provider about improving the look of it, hopefully that's possible; worst case scenario we live with it for a while and improve things down the line.

  • Registered Users Posts: 6,136 ✭✭✭The Continental Op

    Excuse the dumb question but I assume the ballast in necessary because you are not bolting the mounting kit down to the roof?

    Wake me up when it's all over.

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  • Registered Users Posts: 118 ✭✭simpsimp

    Correct - there are two ways to mount to a flat roof - either screw into the roof membrane, which is a bit involved, as you'll to make sure it's still watertight - or weight down the mounting system with something very very heavy. Hence the 8 foot reinforced concrete fence posts that I now see each morning!

  • Registered Users Posts: 6,136 ✭✭✭The Continental Op

    Could you not strap across the roof? As in extend the base framework of the mounting kit slightly out over the roof then tie that in under the roof?

    Wake me up when it's all over.

  • Registered Users Posts: 2,215 ✭✭✭Citizen  Six

    That sounds like it would be just as ugly as the concrete posts.