If your turbine vent is in good condition turns properly and has no missing fins the leak may be occurring around the base of the vent.
Roof whirlybird leaking.
However when there is rain and no wind water can enter the attic and land on the insulation since the blades are not moving.
Some roof leaks are tough to locate.
The spinning capacity of the whirlybird will decrease if a foreign object finds its way through the vents and into the turbines.
Most vents have an integrated base flashing typically made.
In the event the turbine becomes damaged the whole vent will require replacing.
At roof leak services we specialise in the supply and install of quality whirlybird products.
When properly installed a whirlybird has a completely waterproof seal that ensures that no rain can leak through the membrane.
Twista whirlybirds are 100 waterproof.
So how effective a whirly bird will be for your roof depends on what sort of roof you have.
A closed attic space is needed to force the whirly bird to draw air through the vents.
Trowel the roofing tar into the leak on the underside of the roof deck using a putty knife.
Fix a leaky roof vent pipe with a oatey rubber gasket.
The most popular whirlybird product that we install and in requested by customers is the ausralian made ampelite spinaway whirlybird.
Often water runs to openings in the vapor barrier such as at ceiling light fixtures.
Sometimes the water shows up at a ceiling spot distant from the leak.
Otherwise the whirly bird will just draw air through the gaps in the roof tiles locally and not produce much cross ventilation.
Normally when there is wind and rain no water will enter the attic space due to the blades moving around.
Do whirlybird vents leak.
If your ceiling has a plastic vapor barrier between the drywall and the attic insulation push the insulation aside and look for flow stains on the plastic.
My home has three whirlybird turbine vents on the roof.