• Home
  • DIY
    • Self build
    • Projects and advice
      • Bathroom
      • Building, brickwork and masonry
      • Ceilings
      • Cleaning
      • Concrete work
      • Damp, rot and infestation
      • Drains
      • Electrical
      • Fireplaces
      • Floors
      • Garden
      • Heating
      • Insulation
      • Kitchen
      • Lighting
      • Lofts
      • Painting and decorating
      • Plasterwork
      • Plumbing
      • Roof and guttering
      • Safety
      • Security
      • Tiling
      • Walls
      • Windows
      • Woodwork
    • Glossary
    • Know your tools
    • Know your materials
  • Cost guides
  • News
  • Community
Facebook Twitter Instagram
lets-do-diy.com
  • Home
  • DIY
    • Self build
    • Projects and advice
      • Bathroom
      • Building, brickwork and masonry
      • Ceilings
      • Cleaning
      • Concrete work
      • Damp, rot and infestation
      • Drains
      • Electrical
      • Fireplaces
      • Floors
      • Garden
      • Heating
      • Insulation
      • Kitchen
      • Lighting
      • Lofts
      • Painting and decorating
      • Plasterwork
      • Plumbing
      • Roof and guttering
      • Safety
      • Security
      • Tiling
      • Walls
      • Windows
      • Woodwork
    • Glossary
    • Know your tools
    • Know your materials
  • Cost guides
  • News
  • Community
lets-do-diy.com
You are at:Home»Projects and advice»Repairing plaster walls

Repairing plaster walls

Summary: Learn how to repair and patch plaster, patch small holes in plaster, patch large holes in plaster and repair a corner using plaster.


Repairing an area of damaged plaster is called patching. The size of the damaged area will determine the method of repair you use.


Small holes

If the hole is smaller than 50mm (2 in) wide, fill the crack with a single layer of patching compound slightly shallower than the surface of the surrounding wall. Once dry, apply finishing plaster. Apply the plaster in strokes with a trowel going in both directions across the hole.


Fill in the damaged area using a plastering trowel gradually building up the layers.

Large holes

Larger areas of damage can be patched using a one-coat plaster. Always mix the plaster according to the manufacturer’s instructions, but generally 1kg of powder is mixed with 500ml of water. As a rough guide, 10kg should cover about 1.5 sq m (1.8 sq yards) at a thickness of 10mm (4in).

  • Use a cold chisel and a lump hammer to chip away the crumbling plaster until the surface is firm all round.
  • Brush away dust and debris from the damaged area. If the brickwork or blockwork has been exposed splash water over the area.
  • Having mixed the plaster, fill in the damaged area with a plastering trowel or filling knife held at a slight angle. Build up the level gradually, letting each layer stiffen slightly but not dry, before applying the next layer.
  • If the wall is to be decorated with wallpaper apply the ready-mix plaster until it is level with the original plaster surrounding the damaged area.
  • After the plaster has completely dried out, use a power sander or a fine abrasive paper to smooth the area. Wear protective goggles and a facemask when carrying out this task.
  • If the wall is to be painted, leave a 3mm recess from the top of the surrounding surface area to apply a coat of finishing plaster to produce an even smoother finish.
  • When the undercoat is tacky, use a nail or sharp edge to score the plaster to make a key for the finishing coat.
  • When the undercoat has set mix the finishing coat in a bucket until you have a creamy consistency similar to melting ice cream.
  • Apply the finishing coat with a trowel, tying in the edges to the surrounding wall surface.

Temporarily fix a batten vertically to the wall on one side of the damaged area.
Fill the damaged area with plaster making sure it is flush with the edge of the batten.
After fixing the anglebead in place, apply plaster to the area with a trowel and tie it in to the edge of the existing plaster.

Repairing a corner

  • To repair a damaged corner, knock away the crumbling and loose plaster with a cold chisel and lump hammer. Then brush away any dust and debris.
  • Temporarily fix a batten vertically to the wall on one side of the damaged area to give you a straight edge. A spirit level can be used to check the edge of the batten is flush with the surface of the undamaged wall. Position the nails as far away from the corner as possible to avoid causing more damage to the plaster. Leave the nail heads protruding to make it easier to remove the batten when the plaster has set. 
  • Fill the damaged area with plaster using a plastering trowel. Make sure the plaster is flush with the edge of the batten and ties in with the existing plaster.
  • When it has set, move the batten to the adjacent wall and repeat the process to produce a sharp angle.
  • If you need to apply a finishing coat, repeat the process of fixing the batten to both sides of the corner.
  • To finish the corner use a corner trowel to take away the sharp edge.
  • If a corner is being repeatedly damaged, it will need reinforcing with metal angle bead.
  • Cut the anglebead with tinsnips or a hacksaw to the required length. Fix the anglebead to the corner with dabs of plaster 600mm (2ft) apart on both sides of the corner. Use a straight edge and a spirit level to check the anglebead is vertical and that the corner will not protrude above the surface of the plaster.
  • Apply the plaster with a plastering trowel, tying it in to the edge of the existing plaster and to the edge of the anglebead.

Tools needed

  • Trowel
  • Cold chisel
  • Lump hammer
  • Plastering trowel
  • Filling knife
  • Power sander
  • Spirit level
  • Tin snips
  • Hacksaw

Materials needed

  • Patching compound
  • Finishing plaster
  • Fine abrasive paper
  • Angle bead

Related projects

  • Fixing plasterboard to a stud wall
  • Painting new plaster
  • Plaster interior walls
  • Plasterboarding a ceiling
  • Plastering over artex
  • Repairing plaster walls
  • Skimming plasterboard

Related cost guides

  • Average cost to decorate a room or house
  • Average cost of plastering
  • Average cost to tile a bathroom
  • Average cost to tile a bathroom
  • Average cost to fit a bathroom
Recent Comments
  • Vic on Is Christmas a good time for DIY?
  • Anonymous on Average air source heat pump cost (2022)
  • Reggie on Prepare your home for moth season
Latest News
0

Potential DIY home improvement trends for 2023

1

Is Christmas a good time for DIY?

0

Design trends for 2022 and 2023

0

Product Review: Handsaws

Popular Guides

Average air source heat pump cost (2022)

Average French doors cost

Average cost of a new kitchen

Which oven or cooker should I buy?

Popular Projects

Laying ceramic floor tiles

Open vent boilers

Removing rust from metal

Patio and driveway repairs

DIY Categories
Bathroom
Building, brickwork and masonry
Ceilings
Cleaning
Concrete work
Damp, rot and infestation
Drains
Electrical
Fireplaces
Floors
Garden
Heating
Insulation
Kitchen
Lighting
Lofts
Painting and decorating
Plasterwork
Plumbing
Roof and guttering
Safety
Security
Tiling
Walls
Windows
Woodwork

Self Build Guide
How to find a building plot
Evaluating a building plot (2023)
How to get a self build mortgage
Self build construction options
Self build architect and design considerations (2023)
Self build planning permission and legal consents
© 2023 lets do diy ltd | ebuild
  • Home
  • About
  • Contact us

Type above and press Enter to search. Press Esc to cancel.

We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
Cookie SettingsAccept All
Manage consent

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
CookieDurationDescription
cookielawinfo-checkbox-analytics11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional11 monthsThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy11 monthsThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
Functional
Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
Performance
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Analytics
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
Advertisement
Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
Others
Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.
SAVE & ACCEPT