A valley is the channel where two roof slopes meet, and a flashing is the metal or membrane that seals a junction such as a wall, vent or chimney. When valley iron rusts or flashing perishes, water gets under the tiles. We repair or replace them and seal the edges.
Valley and flashing jobs
Valley repairs and replacement
The valley collects runoff from two slopes and sends it to the gutter. Leaves collect there, rust sets in, and a pinhole in the metal becomes a steady drip in the roof space. We lift the tiles along the valley, check the iron and the timber under it and decide between patching and replacing.
Replacement means lifting the tiles on both sides, fitting a new valley iron, then relaying the tiles with a proper gap on each side. It costs more than a patch, but a rusted valley with several holes needs it.
Valley seal installation
We fit a seal along the tile edges beside the valley iron. It closes the gap between the tile and the metal. That blocks wind-driven rain from being pushed up and under the tile, and it stops leaves and nesting material packing into the gap.
Flashing repairs and replacement
Flashing seals the joints: where the roof meets a wall, around vents and pipes, and at chimneys and skylights. Old flashing cracks, lifts or loses its sealant. Pipe boots go hard in the sun. We replace the failed section and seal it, and we check the fixings.
| Where | Common fault | Usual repair |
|---|---|---|
| Roof to wall junction | Lifted or cracked flashing | Replace flashing, reseal |
| Pipe or vent through the roof | Perished rubber boot | Replace boot or flashing |
| Valley | Rust, blockage, lifted tiles | Clear, patch or replace valley iron |
| Gable edge | Open joint between tile and wall | Lead or metal flashing |
| Fixings and joins | Dried sealant | Reseal, replace fixings |
Lead flashing
Lead is soft and can be moulded over tile profiles, which suits gable ends and awkward junctions. It sits tight to the tile and lasts a long time. We form it to the profile, fix it and seal the top edge. It costs more than basic metal flashing, so we tell you where lead earns its price and where plain flashing will do.
Example: a vent flashing nobody asked about
One customer asked for ridge re-pointing. During the inspection we also found cracked tiles and a cracked vent flashing, and the quote covered all three.
“Nathan inspected the roofs of my two properties and provided a competitive quote for the Roof Repointing work. He also found some cracked tiles and a crack on a vent flashing. His quote included fixing these as well. He did an excellent work and completed both jobs on time. I would highly recommend him for any roofing work.”
For the causes of a leak that has not shown itself yet, see leak detection and repairs.
Think a flashing has failed? We price after we have been on the roof, not before. Book a time on 0430 545 669 or the form.
Questions about valleys and flashings
How do I know if the valley is leaking?
Stains on the ceiling under the valley line, rust spots visible from the roof, and water backing up in heavy rain are the signs. Debris in the valley adds to it.
Can a rusted valley be patched?
For one or two small holes, sometimes. If the iron is rusted along its length, replacing it is the lasting fix.
Is lead flashing worth it?
On gable ends, around chimneys and at awkward junctions, yes. On straight runs, standard flashing does the job at a lower cost.
Can silicone fix a flashing leak?
It can slow a leak for a short time. A failed flashing needs replacing or properly re-fixing, with sealant as the final step.