Noise and metal roof

I am building a new house here. It is a single storey house and will have a hip permaclad roof. All rooms will have a false ceiling (gypsum or board) at a height of approx 10 feet. The metal roof will be about 6-8 feet about the false ceiling at the ridge. We are told by friends that a metal roof can be very noisy due to overhead sounds such as rain, birds etc. We are considering fibreglass rolls to be applied directly under the metal sheets of the roof. Will this dampen sounds to any significant degree? Will it reduce heat in the rooms below? The decision is an important one as fibreglass and the labour costs of installing it are considerable in this part of the world. Since the roof is scheduled to go up in a couple of days, I would greatly appreciate an early reply. Thanks in advance.		madhumal sajeev 8/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17766/find/
Are you going to have roof decking? What are you doing for ventilation?		Todd Miller Isaiah Industries, Inc. 8/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17767/find/
From what I make of it, the roof structure will consist of the following: Permaclad sheets fixed to purlins which lie horizontally on the rafters. The false ceiling will come below at the height of the walls. If we decide to have the fibreglass, the fibreglass will go on in sheets between the permaclad and the purlins from eave to eave. For ventilation we plan to have grills in the eaves and two large vents in the ceiling. Hope this helps		madhumal sajeev 8/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17768/find/
Generally, this is very different construction than what we use or suggest here in the states. Because there is no decking, I would suggest some insulation for sound deadening. Since ventilation may be limited, be careful to make sure that the insulation does not potentially trap moisture against the back side of the roofing. Again, your situation has issues which we do not typically encounter here in the states.		Todd Miller Isaiah Industries, Inc. 8/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17769/find/
Thank you for your advice.		madhumal sajeev 8/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17770/find/

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