How to Prepare Your Walls for Plastering
Having a room plastered is one of the most transformative improvements you can make to your home, but a little preparation on your part can make the process smoother, faster, and potentially less expensive. In this guide, we’ll walk through everything you should do before your plasterer arrives, and explain what the plasterer will handle themselves.
Lee on what he wishes every customer would do
What I wish every customer would do is clear the room and cover the floor before I arrive. That’s the gold-star prep. An empty room with the floor protected means I can get in, get set up, and get on with the plastering rather than spending the first morning moving furniture and laying sheets. Plastering is one of the messiest jobs in the trade, no matter how clean and tidy I work, so the more clutter in the room, the more time goes into protecting it. I’ll always help move things if needed, but if the customer can do it before I get there, the job goes faster and the quote can come down.
Before You Book: What to Consider
Before booking a plasterer, it’s worth thinking about a few things that will affect the job:
Electrics and Plumbing
If you’re planning any electrical or plumbing work, get it done before the plastering. Moving sockets, adding lights, rerouting pipes, or installing a new radiator all need to happen before the walls are plastered. Doing it the other way round means your fresh plaster gets chased and patched, which is wasteful and never looks as good.
If you’re not sure whether you need an electrician first, ask your plasterer during the quote stage. A good plasterer will advise you on the right order of work.
Painting and Decorating
Don’t paint or wallpaper before plastering - it seems obvious, but it’s worth stating. Plaster needs to go on a clean, stable surface, and any decoration will be destroyed during the process. Plan your painting for after the plaster has fully dried, which typically takes two to four weeks.
Other Trades
If your room is part of a larger renovation, coordinate with your plasterer on timing. Plastering should generally happen after first-fix electrics and plumbing, after any structural work, and before second-fix and decorating.
The Week Before: Room Preparation
Clear the Room
The most helpful thing you can do is clear the room as much as possible before your plasterer arrives:
- Remove all furniture - if you can empty the room completely, that’s ideal. Your plasterer can work faster and more effectively in an empty room, which may save you money
- If furniture can’t be moved - push everything into the centre of the room and let your plasterer know in advance. They’ll cover it with dust sheets, but be aware that plaster dust gets everywhere
- Remove curtains and blinds - take down curtains, blinds, and any curtain poles or tracks that are in the way
- Take down shelves and fixtures - remove shelves, picture hooks, mirrors, and anything mounted on the walls being plastered
- Remove light fittings - if possible, remove lampshades and any wall lights. If you’re not comfortable doing electrical work, leave it for the plasterer to work around
Lee on best and worst prep
The gold-star is a clear room with the floor covered, simple as that. The worst preparation was a hoarder’s house where the customer had agreed to clear the room but hadn’t, the sofa was still there, all her belongings were still there, and me and my assistant had to move and cover everything before we could start. I’d never embarrass a customer to their face about poor prep, but I have muttered a few things under my breath over the years. The simple truth is the better the prep, the better the job goes, and the customer benefits from it.
Protect What Stays
For anything that can’t be removed:
- Carpets - ideally, remove carpets from the room. If they’re fitted and can’t be removed, your plasterer will lay dust sheets, but plaster drips can stain. If you’re planning new carpet, have it fitted after plastering
- Hard floors - dust sheets will protect hard floors, but be aware of plaster splashes. If you have expensive tiles or hardwood, consider additional protection
- Doorframes and woodwork - your plasterer will typically mask off woodwork with tape, but you can speed things up by removing any door furniture (handles, hooks) in advance
Access and Practicalities
- Parking - make sure your plasterer can park close to the property. They’ll be carrying bags of plaster, plasterboard, and equipment
- Water supply - plasterers need running water to mix plaster. Make sure the water is on and accessible
- Power - they’ll need electrical power for mixing drills, lights, and other equipment
- Access - if the room is upstairs, make sure the route from the front door to the room is clear for carrying materials
What Your Plasterer Will Handle
You don’t need to do everything yourself. Here’s what a professional plasterer will take care of:
Wall Preparation
Your plasterer will assess and prepare the wall surface. This includes:
- Removing loose or blown plaster - old plaster that sounds hollow when tapped or crumbles when touched needs to come off. Your plasterer will strip this back to a sound surface
- PVA or bonding agent - walls are treated with PVA or a specialist bonding agent to ensure new plaster adheres properly
- Filling major defects - large holes, deep cracks, and uneven areas will be filled or built up before the finishing coat
- Beading - metal or plastic beading is fitted to external corners and edges to create clean, straight lines
Protecting the Room
Professional plasterers carry dust sheets and masking tape as standard. They’ll protect floors, mask off woodwork, and cover anything that can’t be moved.
Waste Removal
Old plaster, packaging, and other waste should be cleared by your plasterer. Check this is included in your quote - most professionals include basic waste removal as standard.
Lee on the prep behind the scenes
Eighty percent of a good plastering job is in the preparation, and most of that happens before a single trowel of plaster goes on. Checking the wall for damp first, because if the brick is wet you can’t just skim over and hope. Raking out loose material, sealing the wall with PVA or grit PVA depending on the surface, fitting beads on all the external corners and stop edges. Grit PVA is the big improvement of the last few years, it gives the plaster something to grip onto and stops the kind of failures I’d see early in my career, like plaster sheeting off because the surface underneath wasn’t keyed properly. None of that prep is glamorous, but skip it and the finish lets you down within months.
What to Expect on Plastering Day
Noise and Dust
Plastering is messy work. Expect:
- Dust when old plaster is removed or walls are prepared
- Noise from mixing drills and scraping tools
- Splashes of plaster and water, especially during mixing
- Foot traffic between the room and the plasterer’s vehicle
Timing
A skilled plasterer will typically complete a standard room (walls and ceiling) in one to two days. However, they’ll often need to return the following day for a final trowel, so don’t plan to use the room immediately.
Drying Time
Fresh plaster needs time to dry before you can paint or wallpaper:
- Touch dry - 24 to 48 hours
- Ready for painting - two to four weeks, depending on the room’s ventilation, heating, and the time of year
- How to tell - wet plaster appears dark; it lightens to a uniform pale pink as it dries. Don’t paint until the entire surface is a consistent light colour
Keep the room ventilated during drying. Open windows where possible, but avoid directing heaters at the walls, as forcing the drying process can cause cracking.
Lee on drying times
My standard advice to customers is to allow at least a week for the plaster to dry before painting, sometimes longer in winter or in a poorly ventilated room. Then apply a mist coat, watered-down paint roughly 70 percent paint to 30 percent water, before your first two proper coats. The mist coat seals the surface and shows up any areas that need filling before the final paint goes on. The most common mistake is impatience: painting too early traps moisture, causes peeling and ruins the finish. I’ll also tell customers that the plaster will look patchy when it’s drying, lighter in some areas, darker in others, and that’s completely normal. It’ll even out once it’s dry and painted.
Common Mistakes to Avoid
Don’t Paint Too Soon
This is the most common mistake. Painting over plaster that isn’t fully dry traps moisture and can cause peeling, bubbling, and staining. Be patient and wait for the plaster to dry completely.
Don’t Skip the Mist Coat
Before painting, apply a mist coat - emulsion paint diluted with water (typically 70% paint, 30% water). This seals the plaster and provides a key for subsequent coats. Don’t use vinyl silk or any paint with a high sheen as a first coat on new plaster.
Don’t Hang Things Too Soon
Avoid drilling into fresh plaster for at least two weeks. The plaster needs to cure properly before you add the stress of fixings.
Don’t Ignore Underlying Problems
If your walls have damp issues, don’t just plaster over them. Address the cause of the damp first, or the new plaster will fail just as the old plaster did. A good plasterer will identify damp during the quote stage and advise on treatment.
Checklist: Preparing for Your Plasterer
Here’s a quick checklist to work through before your plasterer arrives:
- Complete any electrical or plumbing work first
- Clear the room of furniture, or move it to the centre
- Remove curtains, blinds, shelves, and wall fixtures
- Remove or roll back carpets if possible
- Ensure parking is available close to the property
- Check that water and electricity are accessible
- Clear the route from the entrance to the room
- Discuss any concerns with your plasterer before the day
Following these steps will help ensure a smooth, efficient plastering job with the best possible results. If you have any questions about preparing for plastering work, don’t hesitate to get in touch - we’re always happy to advise.