Finishing flashing on replacement windows - current practice?

Hi, we've just had a number of old windows replaced due to rot (west facing on the coast), with two different builders involved (one got sick so had to get a 2nd in to keep things moving along).

My question is regarding the finishing of the window flashing - our 1st builder simply bent the aluminium flashing down over the weatherboard immediately under the timber window and nailed it into the weatherboard. He said that all we then had to do was paint over it to match the weatherboard colour. From looking at the other original windows in the house, this was how the flashing was finished also. Our 2nd builder, however, has said that to finish the flashing properly we should be removing the weatherboard under the window and nailing the flashing down behind it before replacing the board. Which is the best/current/standard practice for the above?

Also, we have already experienced some water coming in under the architrave around the first window when we had a big storm with particularly wild winds (though normal rain not seeming to cause a problem) - would this be due to the way the flashing has been finished? Would it be fixed by redoing the flashing to sit under the weatherboard or should we be looking at some further waterproofing on the exterior where the weatherboards meet the window? If so, what is a sensible approach?

Sorry for the long post!! :)


Read and reply to the full thread at RenovateForum.com....