The construction of the houses has to be somewhat modified from houses in most areas.In the houses on the highway and in the noisiest areas of this site there will be a need for specialised double glazing and special acoustic seals will have to be fitted to the doors.All exterior doors in this especially noisy pocket will have to be solid core wood doors with hinges.Every house built on this site,not just those adjacent to the highway or nearest to the airport,will require high density insulation materials in the roof.Not only will all the roofs need insulating,the exterior walls will be required to be double brick.All ceilings will require double thickness plaster board to be used in the construction.In the noisiest areas mechanical ventilation will have to be installed in the exterior walls.In those areas with sealed windows it will be necessary to fit fans with absorbers to cut out the noise in those particular houses.Air conditioning units could also be fitted in the ceilings of such houses but this is substantially more expensive than fans,and may not be needed on this site.