My plan is to order triple-glazed Veluxes with solar control glass (you can get it on special order I think) then fit external solar shutters when we can afford them.
If your Velux are top pivoting, with a handle at the bottom, the support springs may be insufficient to hold up another pane.
If newish centre pivoting, with 24mm thick double glazed units, you could just order a tripple unit to your spec from a glazier. Would probably be a chunk cheaper than special order from Velux.
Thanks that's good to know. Current rooflights are centre pivot but a crap cheap brand so planning to replace with Velux (also because we really want the solar electric ones for various reasons).
If your Velux are top pivoting, with a handle at the bottom, the support springs may be insufficient to hold up another pane.
If newish centre pivoting, with 24mm thick double glazed units, you could just order a tripple unit to your spec from a glazier. Would probably be a chunk cheaper than special order from Velux.