Problems with window and door seals?

[robbierazz]

Hi There,

I have uPVC double glazed windows and doors that the previous owner had fitted before selling the house to me.

Anyway, I live near a fairly busy road and have noticed that the sound insulation isn't fantastic, as cars can be clearly heard driving past even whilst windows are closed.

I went to see my neighbour the other day as I live in a semi detached property, and noticed that whilst I was there I couldn't hear any traffic noise at all, except when a loud vehicle like a bus went past, but even then the noise was only just noticable. They also have double glazing and I inspected it closely and the airgap between the two panes 'appears' to be the same as mine, so I can't understand why their sound insulation is so much better.

I have also noticed some 'black spotting' on the window frame of my bedroom window, which I assume is mold? This seems to indicate that either the seals are not very good or the sealant hasn't been applied very well around the window frame? Could this also be why the sound insulation isn't very good?

I am happy to do any remedial work myself but wondered whether anyone had any suggestions as to what to do about the problem?

Many thanks in advance,
Rob.

 

[philipdayton]

Rob,

It is possible that the windows are under size and that the sealant around the window is not blocking out the sound.
If there is mould on the internal sealant that could be caused by internal condensation or it could indicate that there are gaps in the external sealant allowing moisture through, which again would not help your sound insulation.

Just a thought

 

[robbierazz]

Hi Phillip,

Do you suggest that I get hold of some external mastic sealant and go round all the window frames with it then?

I am happy to do that if you think it may help.

Thanks,
Rob.

 

[philipdayton]

It certainly won't do any harm and it's a good cheap fix.
It's where i'd probably start.

 

[robbierazz]

Ok then, thanks Philip.

Do you suggest I remove the old sealant first, or just apply fresh sealant over the top of the exisiting stuff? Or does it not matter?

Thanks.

 

[JohnD]

Would it help to explore for a gap between the window frame and the wall, and fill it with expanding foam?

 

[philipdayton]

As John says above, remove the old sealant first and if the gap is big enough fill with expanding foam first (be very careful not to use too much)
Then apply fresh sealant once the foam has 'gone off'.
If the gap is only 5mm or less, just get as much sealant in as you can.

 

[robbierazz]

Ok thanks for that.

Anyone got any suggestions as to the easiest way to remove the old sealant? Is there a preferred method that I should use?

Thanks,
Rob.

 

[JohnD]

 

[robbierazz]

Hi JohnD,

That's excellent, many thanks for that. I have an account with screwfix so will get some remover.

Also, what sealant do you suggest would be the best to use? I am intending reapplying the sealant to both the inside and exterior of the windows. I have heard that there is an accoustic sealant??

Thanks,
Rob.

 

[JohnD]

Don't know about that. Silicone sealants are usually better than any acrylic or caulking stuff, but more difficult to apply.

FWIW, when you put the foam in any cavities, my thoughts are in //www.diynot.com/forums/viewtopic.php?t=78673