PV on roof trusses

[BruceB]

Around a year since my last PV job but I have one to do on a 60's semi with roof trusses (35mm wide x 100mm deep) and standard tiles. What is the best practice for dealing with these now: bolting on strengthing members alongside and using what I think of as standard schuco (for example) roof hooks, or is there something on the market that you can put directly into the truss with enough smaller screws?

 

[The Solar King]

Have a look at Mount Solar. Anglo-German mounting designed and tested for UK engineered trusses. Tested by BRE for MCS012. Easy to calculate wind loading. Screw straight in to truss. Quick and no messing.

 

[BruceB]

Thanks. Looks feasible. I'll get in touch with them. I am a little surprised though that it appears they are saying you can use 2 or 3 x 6mm screws on 35mm trusses and still have the necessary pull out resistance and edge spacing required under Eurocodes that Worcester has mentioned in posts over the last year or two.

 

[The Solar King]

It is OK. Red Tip do something similar, but having used this, I thought their brackets a little flimsy. Just work out the number of brackets you need, it may be a few more at leading edges. We have never spaced at 1200mm only on vertical panel orientation. Remember our wind loadings are higher up here than yours will be. Speed of install is the key in all this. You won't spend hours banging extra bits of wood into roof structures.