Filling large gaps around window frame and reducing noise

ic

I had a bay window replaced last year, which the following winter turned out to be very noisy during storms - whistling and bagpipe noises.  The window fitter initially did turn out to refit some external trims and apply more sealant, but this didn't kill all the noises and he was out of ideas.  Not long after my relationship with him turned sour after he delayed work on other renovations in the house, and made mistakes mis-measuring both the bifolds and the front door - they are resolved, but I'm confident he'll never talk to me again.

After a noisy stormy night in desperation I ripped off the internal trims around the window to find large gaps around the window.  On one side it was 2 cm, on the other about 4 cm.  Across the top the gap varied from 2 cm down to 1 cm.  On the widest gap he has screwed a piece of timber to the frame which fills 2/3rds of the gap.

I raked out the negligible dribbles of expanding foam he'd installed to the sides (nothing to the top), and then filled everywhere I could, cut back and then re-trimmed.  This has resolved the wind noises - however I still feel the external noise is too much.  Ultimately between us and the outside world are two thin pieces of trim and expanding foam.

Is there a better solution to filling the gap that could also reduce the sound getting through?  I feel something that can dampen noise would be better, but unsure what that could be.  Mortar, expanding foam rods, timber, PIR insulation cut to size, etc?

maisie_cat

That's awful, they forgot the window foam in the gap, which is then covered with a silicone bead. Did you get a building regs/fensa/certass signoff?
Same happened to me some years ago so get them back to fix it or failing that get some window foam, not ordinary expanding foam, and fill the gap. 

ic

Yes I do have a fensa cert. I've filled the gap with this foam https://www.screwfix.com/p/soudal-soudafoam-expanding-foam-gun-grade-750ml/5026d?ref=SFAppShare, but it's still noisy. My other issue is I've had made to measure blinds installed, which I'd lose if the frame were remade to fit, so I'm keen to improve what I now have. 

FreeBear

Expanding foam should reduce the noise considerably - It may pay to squirt some in from the outside to ensure the void is completely filled. Just be careful not to pump too much in as it could cause the frame to distort.

Quite a shoddy fit really - The frames are normally made 5-10mm smaller than the opening to allow for expansion. Anything more smacks of poor measuring.

markin

The bottom must need doing from the outside, i would guess.