Set up the safe room before the first drill starts
Choose the room furthest from the planned work, ideally one with a door that closes properly and no work scheduled inside it for the whole project. Stock it properly: a litter tray in one corner, food and water in another, a covered hiding place, a scratching option, and a worn jumper or blanket that carries your scent. A radio or television playing at low, steady volume in that room blurs the sharper bangs from outside far better than silence does.
Move her into that room for short, pleasant spells several days before the builders arrive, feeding a favourite meal there and playing there, so on the first noisy morning the room already reads as hers. A cat shut into an unfamiliar room on the same morning the drilling starts has two problems at once, and she will spend the day trying to solve the room instead of resting through the noise.
Guard the door like it is the whole plan
Most building-work disasters for cats are door disasters, not noise disasters. A front door propped open for materials, a safe-room door left ajar by someone fetching tools, and a frightened cat is suddenly loose in a house full of open exits, ladders, and unfamiliar boots. Put a clear note on the safe-room door, tell every worker on site that a cat is behind it and it stays shut, and use a sign on the front door too if deliveries are coming and going.
Move her into the safe room before anyone arrives each morning, not after the vans pull up. The same applies in reverse at the end of the day: check that tools, cables, open paint tins, and gaps in floorboards or walls are cleared or closed before she is allowed to explore the worked-on rooms, because dust, wet plaster, and exposed fixings are hazards a curious cat finds quickly.
Read how she is actually coping
Some cats sleep through astonishing noise once they have a hide and a routine. Others stop eating, hide continuously, toilet outside the tray, or groom one patch of fur obsessively for the duration of the project. Watch her appetite and tray use across the first two days, since those tell you more than whether she flinches at a drill.
If she is not eating, is panting, drooling, or has diarrhoea or repeated vomiting during the work, or if she remains completely withdrawn after the house is quiet again each evening, contact your veterinarian for advice about her specifically. Prolonged work lasting weeks, with a cat who is deteriorating rather than settling, is also a conversation to have with the vet and, if you have a trusted option, about temporary boarding or a stay with a familiar person away from the site.
Keep the day's rhythm boringly normal
Feed at the usual times, in the safe room, and visit at natural breaks rather than constantly opening the door to reassure yourself, which lets noise in and teaches her the door means commotion. A play session in the room each evening burns off the tension of a day spent cooped up and helps her sleep. Keep your own behaviour unhurried around her; a household tiptoeing and whispering about the cat convinces her something is badly wrong.
Coordinate who does what, every day
Building days scramble household routines, and cat care gets dropped precisely because everyone assumed someone else had done it. Agree each morning who moves her into the safe room, who checks water and tray at midday, and who does the end-of-day hazard check before she comes out. KinsLe's Care Teams lets you assign those exact duties to named family members for each pet and marks each task complete with a timestamp, so in the middle of a renovation nobody has to guess whether the midday check actually happened.