These are the questions worth putting to a plasterer, grouped by when to ask them, with a note on what a useful answer sounds like and what should give you pause. For the wider selection process — how many quotes to get, how to shortlist and what to agree before work starts — see how to choose a plasterer.
Questions about the job itself
What do you think caused this?
Plaster rarely fails without a reason. A contractor who treats the symptom without identifying the cause will usually be back.
- A good answer sounds like: “The staining pattern suggests moisture from above rather than rising damp, so I would want the source resolved before I plaster.”
- A weak answer sounds like: “It happens with older houses. We will fill it and it will be fine.”
How much of the existing plaster needs to come off?
This single answer drives most of the price difference between quotes.
- A good answer sounds like: “I will sound the wall and take off whatever is hollow. From what I can see that is roughly this section, but it may run further.”
- A weak answer sounds like: “We will just skim over it.” — without having tapped the surface at all.
What can you not tell me until you open it up?
An honest plasterer will name the unknowns before starting rather than raise them later as extras.
- A good answer sounds like: “If the plaster behind the cupboards has gone, that will add area. I would rather flag it now than surprise you.”
- A weak answer sounds like: “There will not be any surprises.”
Questions about the quote
What is excluded from this price?
Exclusions are where two quotes for the same room diverge. See what a plastering quote should include.
- A good answer sounds like: A written list: painting, waste removal, furniture moving, scaffolding, making good after other trades.
- A weak answer sounds like: “Everything is included” on a quote with no itemisation.
Is this labour only, or labour and materials?
The two are priced completely differently and are not comparable side by side. See labour-only plastering rates.
- A good answer sounds like: “Labour and materials, and here is what I have allowed for materials.”
- A weak answer sounds like: A single figure with no indication either way.
If more damage is found, how is the extra priced and approved?
This is the most common source of dispute on repair work.
- A good answer sounds like: “I will stop, show you, and price it at the same rate before continuing.”
- A weak answer sounds like: “We will sort it out at the end.”
Questions about the work
What are you using, and why?
The material should suit the substrate and the location. See Rhinolite vs cement plaster.
- A good answer sounds like: “Sand-cement as a base coat because it is an exterior wall, then a skim for the finish.”
- A weak answer sounds like: “Whatever we normally use.”
How many coats, and how long between them?
Rushed drying between coats is a leading cause of cracking later. See how long plaster takes to dry.
- A good answer sounds like: A specific sequence with realistic waiting times, including the wait before painting.
- A weak answer sounds like: “It will be done in a day” for a job involving base coat and finish.
How will you match the existing texture?
Repairs that are structurally sound can still look obvious once painted.
- A good answer sounds like: “I will feather the edges well past the repair, and this wall will probably need repainting corner to corner.”
- A weak answer sounds like: “You will not see it at all.”
Questions about timing and disruption
How many visits, and over how many days?
Drying time means most plastering is not continuous work, and the calendar span is longer than the working days.
- A good answer sounds like: “Two visits, about four days apart, and roughly a week before you can paint.”
- A weak answer sounds like: A single duration with no mention of return visits.
Who covers furniture, and who removes the waste?
Plaster dust travels, and old plaster is heavy and awkward to dispose of.
- A good answer sounds like: A clear division of responsibility, stated in the quote.
- A weak answer sounds like: “We will see on the day.”
Questions about afterwards
What does your guarantee cover, and for how long?
Workmanship cover and material failure are different things. See plastering workmanship guarantee.
- A good answer sounds like: A stated period, in writing, with the exclusions named — typically structural movement and unresolved moisture.
- A weak answer sounds like: A verbal “we guarantee our work” with no period and no exclusions.
If the crack comes back, what happens?
Recurrence usually points to an unresolved cause rather than bad workmanship. See why plaster cracks return.
- A good answer sounds like: “If it returns in the same place I will come back and look at it, but if the cause is movement we need to deal with that first.”
- A weak answer sounds like: “It will not come back.”
Reading the answers
The pattern matters more than any single reply. A contractor who asks you questions back, distinguishes what they know from what they are assuming, and is comfortable naming what could go wrong is describing the job as it actually is. Certainty on every point, offered without an inspection, is the answer to be most careful of.
Related guidance
- The selection process — how to choose a plasterer.
- Preparing the enquiry — plastering quote checklist.
- Comparing what comes back — compare plastering quotes.
- Judging the finished work — how to check plastering quality.
Request a plastering quote when you are ready to put these questions to a contractor.