My partner is getting her house ready to rent out (so we can move in together), and one of the things picked up on the Healthy Homes assessment was the draught/gap in several of her windows.  They're all aluminium joinery, and the issue appears to be too much give in the window hinges, so that the window doesn't fully close at the top.

She got a quote to fix the issue, and the installer quoted around $900 to supply and fit replacement hinges for five windows.  Looking at it, I wondered if it would be a relatively easy DIY job - swapping out like for like.

I went to Bunnings but it doesn't seem like there is a direct swap for the hinge we took out.  We bought one which is close, to see how well it would fit in the frame.  We think it would probably be okay, but for a couple of things:

 

1. Because the replacement hinge is a slightly different configuration it makes me wonder if the window would close at the same place.  
2. The part of the hinge which screws into the window frame is different.  The existing hinge mounting is "U" shaped, which acts like a standoff from the window frame and keeps it flush and stable.  The new hinge doesn't have this design, so it does lie flat and when screwed down would probably lie at a slight angle of about 2-3 degrees.

It's hard to describe only in words (and I don't have pictures to share at the moment).  I guess I was posting to find out if there are any experience aluminium window DIYers who might be able to offer some advice or reassurance about this, or if it's too tricky to do and therefore simpler to just pay a professional to get it right.