Can roofing felt get wet?

A little bit, yes — but not for long. It’s made to handle light moisture during install, but if it stays wet too long, it starts to break down. It’s water-resistant, not waterproof.

Here’s the deal with felt and water

Roofing felt (also called sarking or underlay) is there as a backup layer — not the main line of defence. It’s fine if it gets damp briefly during the job, but it’s not built to sit in the rain for days.

A few key things to know:

• Light rain won’t ruin it
  If it gets wet and dries quickly, no drama. Most roofing felts are designed to deal with that kind of exposure.
  
• Constant moisture will cause issues
  If it stays wet — especially in heavy rain — it can start to wrinkle, sag, or tear. Once that happens, it won’t do its job properly under your tiles or metal sheets.
  
• It’s not your finished roof
  Felt is meant to sit underneath everything else. So if the main roofing layer isn’t on yet, the clock’s ticking to get it covered.
  

Bottom line?

Roofing felt can handle a bit of water — but only short term. If rain’s coming in and your roof’s still open, it’s worth pausing the job and covering up.

Not sure if your felt’s been affected?
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