Re: insulating new house due to street noise
Depending on what type of traffic noise you can reduce a portion of the noise with shrubs, trees and fences . A large portion of traffic noise is tire contact with the road surface. Dense shrubs at about 3 ft height will go towards reducing this sound. Along with other plantings and a barrier fence are the first line of reducing the noise that reaches the house.
Originally Posted by neal
Dual pane windows with different thickness of glazing also improves the SPL. The various thickness reduces the noise since they attenaute different frequencies.
Applying rigid faom to exterior also reduces noise infiltration.
I'm sure you don't want to completely redo your 3 year old home so, a simple thing on the interior is apply 5/8 drywall or a special sound proofing drywall to the exterior walls facing the traffic.
I'm not sure how much noise is coming in from the attic but --- sight unseen --- if your attic is insulated creating a conditioned space then adding batt insulation to the ceiling rafters shouldn't be an issue with moisture.
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