Root barrier and green roofs
pat165
Posts: 2
I am looking for a root barrier that is actually effective. I have used the woven type before and even dandelions still seed through it, and then they are a impossible to dig out. There are the fibrous matt type which seem to be more commercial big engineering stuff, but haven't used this. Any experience of one that works to go underneath shingle pathway? I also need one for a green roof. The system I am using is with a hyperlon waterproof membrane, than a polypropelene carpet protection layer, on top of which is a weed barrier, then a tray system to take lightweight growing medium. The root barrier could be the same as before, but I have some fleece, thin but very very tough: I have put scrrews through this and found it difficult to penetrate, and I could put 4 layers of this down. Would this work? What thoughts?
Posts
good weed membrane stops stuff growing up through it from underneath as long as there is something on top (woodchip, gravel etc.) but then you get stuff seeding itself into the gravel and you're back to square one!
what are you planning on growing on the green roof? sedums? because they only have little (thin) roots that form mats only maybe 3- 4 inches deep. what you're thinking about may be overkill, I'd just use black plastic, maybe two layers to be safe on top of roofing felt.