Remove the felt and install a membrane instead, many makes around and you can bond them down.
i just tin sheeted mine box profile stuff seconds and made the ends, ridge tiles, out of the same sheets
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Never used membrane, can you put it straight down with nothing on top ?Remove the felt and install a membrane instead, many makes around and you can bond them down.
ops wind getting under it, you can bond it down with petroleum based glue, or you can use a dedicated glue which is expensive, most people use Unibond or similar.



