Acoustic insulation for rafters - attic conversion

Fracking Cylon

We are looking to convert our attic to a mixture of bedrooms, bathroom and a home office. We live close to a road and want to reduce the traffic noise that comes through the roof. There are lots of products for noise reduction between floors but I'm hoping someone can give me some advice for reducing noise coming into the attic from outside. Any particular products or methods you would recommend? It's a slate roof and will have 2 dormer windows.

Calahonda52

This is going to be v difficult, as u prolly know already
if the soffits are ventilated then you will have mega problem with sound.

The windows should he on the leeward side from the road as should any wall vents

I would only put the sound proofing mula into the bedrooms, not needed in other rooms.
Think about making the bedrooms sound insulated boxes, lining the inside of the rafters with the sound proof material, if you use something like dense wood fibre, it will also help with solar gain, google decrement delay
see my post here
http://www.boards.ie/vbulletin/showthread.php?p=103861278
Have you planning got, is it a third storey
http://www.environ.ie/sites/default/files/migrated-files/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad%2C1657%2Cen.pdf
may help