Damp Proof Course Installation in Essex
Professional DPC injection and replacement using BBA-approved products. Stop rising damp permanently with our guaranteed damp proof course solutions.
What is a Damp Proof Course?
A damp proof course (DPC) is a horizontal barrier built into walls near ground level to prevent moisture from the ground rising up through the masonry. All buildings constructed after 1875 should have some form of DPC, though materials and effectiveness vary.
Original DPCs can fail due to age, bridging (where external ground levels have risen above the DPC), or physical damage. Many pre-1875 properties have no DPC at all. In either case, a new damp proof course can be installed to stop rising damp permanently.
Modern DPC installation uses chemical injection to create a water-repellent barrier within the wall. This is less disruptive than traditional physical DPC insertion and is highly effective when installed correctly.
Signs You Need a New DPC
- • Tide mark of damp on internal walls up to 1 metre high
- • White salt deposits (efflorescence) on walls
- • Peeling wallpaper or bubbling paint at low level
- • Damp, musty smell at ground floor level
- • External ground level higher than internal floor
A DPC creates a barrier to prevent moisture rising through walls
Our DPC Installation Process
We follow a proven process to ensure effective, long-lasting damp proof course installation.
Survey & Diagnosis
We confirm rising damp with moisture readings and identify the best injection height and approach.
Preparation
Holes are drilled at the correct spacing and angle along the mortar course at the chosen injection level.
Injection
BBA-approved silicone cream is injected under pressure, spreading through the masonry to form a complete barrier.
Completion
Holes are made good, and we advise on replastering timelines and specifications for long-term protection.
DPC Installation Options
Chemical DPC Injection
A silicone-based cream is injected into drilled holes along the mortar course, creating a water-repellent barrier within the masonry. Suitable for most wall types.
- BBA-approved products
- Minimal disruption
- 20-year guarantee
From £60-£80 per linear metre
Physical DPC
A physical membrane is inserted into the wall by cutting out a mortar course and inserting the DPC. Used where injection isn't suitable, such as very thick walls.
- Physical barrier
- Suitable for thick walls
- Lifetime guarantee
From £100-£150 per linear metre
Why Choose Our DPC Installation?
PCA Qualified
Our surveyors hold CSRT and CSSW qualifications from the Property Care Association
BBA Approved Products
We only use products with independent BBA certification for proven performance
20-Year Guarantee
All DPC installations come with a 20-year guarantee, insurance-backed for peace of mind
Honest Diagnosis
We won't recommend DPC work if it's not needed - many damp issues aren't rising damp
Complete Solution
We advise on replastering specifications and can complete the full works if required
Fair Pricing
Transparent, fixed-price quotes with no hidden extras or pressure selling
After DPC Installation: The Drying Process
It's important to understand that installing a new DPC doesn't instantly dry out your walls. The DPC stops new moisture from rising, but existing moisture in the masonry needs time to evaporate naturally.
The drying time depends on several factors: wall thickness, how wet the walls are, ventilation, and heating. As a general guide, walls dry at about 1 inch per month under normal conditions. A 9-inch solid wall might take 9-12 months to dry fully.
Replastering too soon is the most common mistake after DPC installation. If you replaster before walls have dried sufficiently, moisture gets trapped behind the new plaster and the problem appears to return. We advise waiting at least 6 months before replastering, or using specialist renovating plaster that can tolerate higher moisture levels.
Damp Proof Course FAQs
What is a damp proof course (DPC)?
A damp proof course is a barrier built into walls to prevent moisture from rising up from the ground. In older properties this might be slate or engineering bricks; in modern properties it's usually a plastic membrane. When the original DPC fails or is absent, a new one can be installed by injection.
How long does DPC injection last?
A properly installed chemical DPC injection using BBA-approved products typically lasts 20+ years, which is why we provide a 20-year guarantee on our installations. The silicone-based creams we use create a permanent water-repellent barrier within the masonry.
How much does a new damp proof course cost?
The cost depends on the length of wall being treated and wall thickness. For a typical terraced house, DPC injection costs £1,500-£3,000. Semi-detached properties typically cost £2,500-£4,500. We provide fixed-price quotes after survey.
How long does DPC installation take?
The injection itself is typically completed in one day for most properties. However, the walls will need time to dry out afterwards, which can take 6-12 months depending on the extent of the dampness. We advise on replastering timelines during survey.
Do I need to replaster after DPC installation?
Usually yes. Walls affected by rising damp contain salts that have been drawn up from the ground. These salts are hygroscopic (attract moisture) and will continue to cause damp patches even after the DPC is installed. Removing contaminated plaster and re-plastering with a salt-resistant specification is usually necessary.
Need a New Damp Proof Course?
Book a free survey to find out if DPC injection is the right solution for your rising damp problem.
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