I would only do that after “ weathering’ hasn’t cured the leak by allowing the stitching to expand into the cloth material.We had a leaking seam on a new awning, and used a spray waterproofer on the seam not had a problem since.
It worked for me on a Dorema awning with a Tencate roof. It’s the stitching that’s needs to expand into the awning material.I know that the advice given here is very true for canvas awnings but I’m not so sure about the more modern awning materials. 🤔
Yes same for modern awning. I had a new Isabella awning and reading the instructions it stated after a few outings in the rain the stitching would expand to seal any gaps made during manufacturing..Apparently its the stitching that swells not the materials.I know that the advice given here is very true for canvas awnings but I’m not so sure about the more modern awning materials. 🤔