A terraced house shares its walls, and a parrot's contact call is designed by nature to carry through forest — your neighbour's living room presents no challenge at all. Total silence is not achievable, and promising it sets everyone up to fail, but the difference between a bird room arranged carelessly and one arranged with sound in mind is the difference between hearing every call through the wall and hearing a muffled version of the loudest ones.
Start with placement, the cheapest insulation there is
Sound loses strength with distance and with every surface it must pass. Put the cage against an internal wall that is not shared with your neighbour, ideally in the room furthest from the party wall, and keep perches and play stands the bird shouts from away from that wall too. A bird calling two rooms away, behind two closed doors, is a background sound; the same bird calling against the shared wall is in your neighbour's room in every way that matters. If the bird must live in a front or back room on the party wall, even moving the cage to the room's far corner and turning the bird's favourite shouting perch inward makes a measurable difference to what travels.
Soak up sound inside the room
Hard, bare rooms amplify: bare floors, plain plaster, and empty walls bounce every call around until the whole space rings. Soft furnishings absorb that energy. A thick rug, lined curtains kept drawn during the loudest hours, upholstered furniture, and full bookcases against the shared wall all reduce both the noise inside the room and the noise leaving it. Heavy fabric panels or purpose-made acoustic panels on the party wall behind the cage catch the direct path of the sound. None of this needs to look like a studio; a normally furnished, carpeted room is already most of the way there compared with a sparse one.
Seal the gaps sound sneaks through
Sound behaves like water: it finds the gaps. The space under the bird room door, a hollow door left open, and open windows in summer carry more noise to neighbours — and to the rest of your house — than the wall itself. Fit a door seal or a simple draught strip, keep the bird room door closed during dawn and evening calling sessions, and think about which windows are open when the bird is in full voice. Ventilation still matters for the bird's health, so seal the leaks around doors rather than sealing the room airtight, and never block the fresh air the bird needs.
Reduce the loudest calling at its source
The two predictable peaks are dawn and the evening flock call, and both respond to management. A cage cover that keeps the bird's morning dark until a civilised hour delays the dawn chorus far more reliably than any panel; uncover at a consistent time and the loudest singing starts when the street is awake anyway. Through the day, a bird with foraging, company, and occupation calls less from boredom and frustration, because much objectionable screaming is a bird filling an empty day. A frank, friendly word with your neighbours — acknowledging the noise and explaining what you are doing about it — buys more goodwill than any material.
The bird's profile can be shared with family members you select, using KinsLe Family Sharing.