What does the room have to do
Not what size it is; what it does. Will both halves be in use at once? How often will the wall move, and who will move it? Does one side ever have amplified sound? The answers decide whether the wall needs a rating, what grade of hardware it needs and whether one person can be expected to run it. A wall specified from the room's use is right far more often than one specified from the opening's width.
Can the head carry it
Every folding partition is top-hung, and an operable wall is the heaviest moving thing in most buildings that have one. Ask what the head is: a beam, a steel, a timber frame, or a suspended ceiling grid with nothing above it. The last one needs a structural beam before any wall can hang from it, and that is a builder item that has to be in the programme early. We check this at quote stage rather than on install day.
Where do the panels go
Stacked against a return, split to both ends, or into a pocket. A pocket is tidiest and most expensive, and it has to be framed before the wall arrives, so the decision belongs at design stage. Ask for the stack depth in millimetres and draw it, because it takes that wall space permanently.
Is the ceiling void sealed
If the wall has a rating, the ceiling void above it is the question that decides whether the rating arrives in the room. A continuous void is an open path between the two halves. Sealing it is usually a builder item. Ask who is doing it, when, and whether it is in the scope, because a rated wall over an open void is the most common way a partition disappoints.
What is in the price
Ask for panels, track, seals, hardware, delivery and installation as separate lines, with anything the builder has to do listed separately so nobody assumes it is in the supplier's scope. Two lump sums cannot be compared. Two itemised quotes can. Ask which grade of wall or door the quote is for, because the same words describe an unrated divider and an acoustic wall.
- Which grade of system, and what rating if any
- Hardware rated for what cycle count
- Seals included at head, floor and jambs
- Stack depth and location
- Head condition, and any beam required
- Ceiling void treatment, and whose scope it is
- Site measure before manufacture, and re-measure on a new build
- Delivery sequenced to the programme, and what finishes go in first
Who services it afterwards
An operable wall needs adjustment with use, and that is not a fault. Ask who services it, whether they service walls they did not install, and whether a scheduled visit can be put on the maintenance calendar. A supplier who quotes and installs and then hands you a phone number that goes nowhere is the expensive option, whatever the price was.