What Causes Blown Plaster and How Do You Fix It?
Category: Plastering & Rendering
Author: Central Scotland Tradesmen
Published: 2026-03-23
Learn the causes, identification, repair options, and prevention tips for fixing blown plaster to keep your walls in top condition.
Blown plaster can often go unnoticed until it starts to cause visible issues, like cracks or flaking. Understanding what causes it, how to identify it, and when to repair it can prevent costly damage to your home.
Understanding Blown Plaster
What is blown plaster?
Blown plaster refers to plaster that has detached from the underlying wall, creating hollow spaces. It often lacks adhesion and may bubble or flake.
Common Causes of Blown Plaster
Poor initial application, excessive moisture, or vibration from construction work are frequent causes of plaster detachment. Additionally, structural movement in older properties can contribute to this issue.
Signs to Look For
Tap the wall lightly - if you hear hollow sounds, your plaster might be blown. Visible cracks and uneven surfaces are also clear signs of damage.
Fixing Blown Plaster
Step-by-step Repair Process
- Identify blown plaster by tapping the wall and looking for hollow noises.
- Scrape away loose plaster with a scraper or chisel until you reach solid material.
- Prepare the wall by cleaning and applying a bonding agent.
- Use fresh plaster to fill the affected area, smoothing it with a trowel.
- Allow drying before sanding and painting.
Plasterer's Tips for Long-lasting Repairs
Tip 1: Address Moisture First
If dampness is the main issue, fix any leaks or condensation problems before repairing the plaster. Consider hiring professional plumbers if necessary. Visit Plumbers in Central Scotland.
Tip 2: Use Quality Materials
Invest in high-quality plaster and bonding agents to ensure your repairs last longer. Professional assistance from Plasterers in Central Scotland is strongly recommended for large areas.
Costs of Fixing Blown Plaster
| Repair Type | DIY Cost | Professional Cost | Time Required | Best For |
|---|---|---|---|---|
| Small Patch Repair | £20-£50 | £80-£150 | 1-2 hours | Minor issues |
| Medium Wall Repair | £50-£100 | £200-£400 | Half-day | Moderate damage |
| Full Wall Restoration | £100-£200 | £500-£800 | Full-day | Severe damage |
| Structural Repairs | N/A | £800-£1500 | Multi-day | Older properties |
| Preventative Plastering | £20-£80 | £100-£200 | 2-3 hours | Long-term prevention |
Choosing the Right Trade Professionals
Seek qualified tradespeople with proven expertise in plastering. Review credentials and check for customer feedback. Services such as Electricians, Joiners, and Roofers might also be needed for related work.
Find Trusted Tradespeople in Central Scotland
Frequently Asked Questions
What’s the easiest way to identify blown plaster?
Tap the plaster lightly - if it sounds hollow, it’s likely blown.
Can I repair blown plaster myself?
Small areas can be repaired with a DIY approach, but larger or structural issues should involve professionals.
What causes plaster to come away from walls?
Excess moisture, poor application, and structural movement are common causes.
How much does professional plaster repair cost?
Professional repairs range from £80 to £1500 depending on the scale of the job.
How can I prevent blown plaster?
Address moisture issues early and use high-quality materials during application.
Do I need structural repairs for blown plaster?
Only if the root cause is structural movement or severe underlying damage.