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GRP Parapet Roof Leaking

Postby masprice » Tue Feb 18, 2020 1:45 pm


I've recently had an extension on a 1930s property.

It is an open plan wrap around to the side and rear, with a parapet roof.

The GRP roof was installed a few weeks ago, but, it has leaked since installation (especially with the weather which we've had recently). The roofers have been back on multiple occasions trying to fix.

There are a few parts of the installation which I'm unsure on, it would be great if someone could cast their eyes over the pictures to see what they think?

My concerns are;

1) The paint has started peeling off the trim around the top edge of the parapet (see images). The trim is shiny, no primer or anything, but the roofers have just re-painted it which I don't think is correct.

This trim looks very shiny and thicker than the other trims that have been used elsewhere on the GRP.

2) Water is penetrating in the top corners of the roof internally, the joists are wet in the corner and dripping. The roofers have said because the property hasn't been rendered down over their trims yet, water is getting in behind it and working its way down slight pitch on the roof to the rear wall.

They have slapped silicone all over this as a temporary measure until it is rendered, but the leak is still present.

3) The trim as mentioned in the first point is not sealed down to the layer below, it is sort of rippling (stuck down in parts and not others). Again, this is shiny and seems a little thicker than the other stuff. It seems as though it has been lapped in to the brickwork enough, hence it isn't sitting flush?

I understand I will need to have another roofer take a look for a 2nd opinion, but, if there is any feedback you guy could give in the mean time that would be great.

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