What are tile roof weep holes?

Tile roofs have small gaps built into them on purpose. These are weep holes - and they are one of the easiest things for a homeowner to mistake for a defect, when in fact they are doing exactly what they should.

Why tile roofs need weep holes

A tile roof is a layered system. Underneath the visible tiles sits timber battens, then sarking (a reflective foil barrier), then the roof space above your ceiling. Water can get under the tiles - from wind-driven rain, from condensation, from frost cycles that lift mortar - without ever reaching the interior of your home.

That water needs somewhere to go. It runs down the sarking and towards the eaves. Weep holes are small openings in the eaves gutter, or in the flashing at the edge of the roof, that let that water drain away safely before it pools and causes rot or mould in the roof space.

Without weep holes, water trapped between the sarking and the underside of the tiles would sit there indefinitely. In Canberra's climate - with hard frosts, strong sun, and temperature swings across the day - that trapped moisture accelerates decay of the timber battens and the sarking itself.

Where weep holes are and what they look like

Weep holes are small - typically 6 to 10 millimetres across - and are usually drilled or formed in the back edge of the eaves gutter or in the lower flashing where the roof meets the wall. You may not notice them unless you look carefully from underneath the eaves or from inside the roof space.

Some roofers place them in the mortar bedding on hip and ridge caps as well, to let moisture out of those joints.

If your roof is sound, you should not see water coming out of weep holes on a dry day. When it rains or after heavy frost, a small amount of damp around these holes is normal - that is water draining from the roof space as intended.

What can go wrong with weep holes

The most common problem is blockage. Dirt, paint, mortar droppings, or leaves can clog a weep hole, preventing water from draining. When that happens, water pools behind the gutter or in the cavities under the roof, and you start to see:

• Damp patches on the ceiling or walls below the eaves
• Mould or discolouration in the roof space
• Soft timber when you probe the battens or fascia

If you suspect a weep hole is blocked, do not attempt to clear it from the ground - roof spaces are high-risk places. A professional roofer can inspect your roof space, identify which holes are blocked, and clear them safely as part of a broader roof health check.

Another issue is poor design. Older tile roofs, or roofs installed without proper attention to drainage, may not have enough weep holes, or they may be positioned where water cannot easily reach them. This is usually found during an inspection and can be addressed by adding weep holes where they are needed.

Damage to weep holes during roof work is also possible - if a roofer is not careful during repairs or restoration, they may accidentally block or block off drainage paths. This is why working with a roofer who understands the full drainage system, not just the visible tiles, matters.

How a roof inspection helps

If you are concerned that your weep holes are not working, or if you are noticing damp in the roof space, a roof inspection will give you clarity. We charge $99 for a comprehensive inspection that includes a physical look at the roof space, detailed photos, and a written report explaining what we find and what needs fixing.

During the inspection, we check:

• Whether weep holes are clear and in the right positions
• The condition of the sarking and battens
• Whether water is pooling anywhere it should not be
• Signs of mould or rot that point to a drainage problem

If the inspection shows that weep holes are blocked, we can clear them as part of a minor repair. If your roof needs more work - such as a restoration to re-bed ridge caps and improve the overall waterproofing - we can quote that separately.

A typical minor repair to address drainage issues runs between $1,400 and $2,500, though simpler fixes can cost less. A full restoration of a concrete tile roof, which includes re-bedding and re-pointing all the ridge caps and ensuring drainage is sound throughout, ranges from $11,000 to $18,000 for a single-storey home. We provide a detailed quote after the inspection.

When to act

You do not need to panic if you see a weep hole. They are supposed to be there. But if you notice any of these signs, it is worth getting a professional look:

• Damp patches or watermarks on the ceiling or walls under the eaves
• Mould, mildew or discolouration in the roof space
• A musty smell in the roof space
• Soft or spongy timber in the eaves or battens when you gently probe it
• Water pooling visibly in the roof space on a dry day

Any of these suggest that water is not draining as it should, and weep holes may be part of the solution.

Next steps

If you would like to know whether your roof's drainage is working properly, book a $99 roof inspection online at leakyroof.com.au/book or call us on (02) 5133 5608. We will examine your roof space in detail, take photos, and give you a clear written report with options to fix anything we find.

If you prefer to start with a conversation, a free roof estimate is also available - just let us know what you have noticed and we can advise whether an inspection makes sense.

We serve the ACT and the surrounding NSW region, including Queanbeyan, and we are here to help your roof stay sound.