Sealing breached felt

[sha256]

I have drilled a 100mm hole through the side of my flat roof for some venting. The hole has breached the felting. What can I use to create a water tight seal between the plastic vent and felt ? I was going to using general purpose silicone but someone mentioned they used it and the bitumen started to seep through the felt???

Also, should I seal the hole first with some flashband ?

 

[terrypin]

sorry, wrong thread.

 

[Burnerman]

Silicone would probably be fine, but Geocell do a kosher roofing sealer - Screwfix 32561. Failing that, and depending on the gaps involved, consider Evercryl (MKM) or Aquapol.
John

 

[sha256]

Silicone would probably be fine, but Geocell do a kosher roofing sealer - Screwfix 32561. Failing that, and depending on the gaps involved, consider Evercryl (MKM) or Aquapol.
John

Cheers John. Just to confirm, should I use the sealant between the brick and felt or the felt and vent ?

Regards

 

[Burnerman]

This stuff remains pretty flexible and does accommodate movement of the felt in the summer months. Apply some in both places you mention to get a good seal.
Just for interest....you say you have drilled a hole in the side of your flat roof.....can you give us a pic, do you think?
John