Pvcu windows - rain coming through the trickle vents

Kins

We have new windows and have experienced rain coming through and forming pools on the cills.

We will be asking the window company to rectify this, but before chasing them I wanted to get my facts right.

How common is this? OH has removed the inside trickle vents and says it is a fundamental design flaw. There is no water bar/upstand formed on the pvcu profile to prevent this happening. Considering the years companies have been making windows I find this shocking.

With the external trickle vents we do not know if the rain is entering the joint between the trickle vent and window.

We strongly suspect the rain runs over the trickle vent, as it should. Then, instead of dripping down, the rain is blown back across the vent and into the pvcu profile. We say this because we are in a windy location and the problem occurs when there are strong winds driving in rain from the east.

Clearly driving rain from the east is not an everyday occurrence. But equally, the windows should be water tight.

Can anyone shed light on this?

Myser

There should be a small roof running along the top of the trickle vent from the outside.

You can close the trickle vent completely however, if water is still getting through then there may be a fault with the design or the way the windows were installed.