Possible to convert concealed drain windows to face drain?

[nebjamin]

Hi all,

I've just had EWI installed. Since the cills on the existing windows were not long enough they have installed overcills that project out past the insulation.

Our windows have concealed drainage. The overcills completely block the drainage slot and they have also siliconed this up.

Their solution is to install face drains, but I can't see how this will work. Surely any water will run past the face drain down the original concealed drainage route, onto the cill (but still in the frame, behind the silicon), to the edges and then out into the insulation.

They are telling me that the frames will fill up until water comes out of the face drain, but surely this would only be true if the edges of the windows where it met the original cill had been sealed. I'm certain they didn't do that.

Interested in what the options are.

Thanks,
Ben

 

[s60tsy]

even if the bottom edge was sealed this would just send drained water to each side of the old cill, the concealed drain holes are about 8mm further up the frame because there are 'ribs' all the way round. the frame would have to come out to seal the holes, and even then you are relying on the sealant holding out for the next how ever many years. If the face drains are positioned correctly they shouldnt hold water, but actually telling you that the frame will hold water as if its ok is a joke IMO

 

[nebjamin]

Thanks, as I thought.

How can/where should the face drains be placed correctly so that water doesn't just run past them and down the original route?

Also.. in a frame that has 2 windows, one on top of the other, if water got in to the frame via the top window I imagine it would run round the outside edge of the frame and approach the concealed drainage hole from the opposite direction than if it got in through the bottom window?

My only thought about how to solve this is to use a dremel or similar to enlarge the gap between the overcill and the frame so that water drains out as it would originally have done but onto the overcill. I had them push the overcills right under the frame as far as they would go for this reason.

Ta