Stop Cavity Wall Claims Before They Happen
A wind-powered ventilation system with a built-in, inspectable insert — so you can prove compliance and help prevent claims & re-work from cavity failures.
How Active Moisture Extraction Works
Unlike passive vents that rely on hope, Active Vent uses wind-powered negative pressure to actively extract moisture from cavity walls - protecting your builds and your reputation
Why Are Cavity-Wall Failures a Leading Cause of New-Build Claims?
According to the National House Building Council (NHBC), DPCs and cavity trays account for around half of the superstructure defects it sees, with blocked or missing weep vents specifically cited. That's a significant cost to the industry - and your reputation.
Traditional Vents Create These Problems:
- They're passive - They can't actively remove moisture, they just hope air flows through
- They trap water during rain - Driving rain can actually push water into cavities
- You can never inspect them - Once installed, there's no way to verify what's happening inside
- Wet insulation kills efficiency - Moisture makes insulation far less effective; damp insulation can let through nearly twice the heat of dry, leading to energy complaints
The result? Callbacks, complaints, warranty claims, and damage to your reputation. Homeowners blame the builder when their energy bills are high or mold appears - even when you followed all the regulations.
How Can You Inspect Cavity Walls After Construction Is Complete?
Until now, the answer was "you can't." Once walls are closed up, cavity quality is a black box. But Active Vent changes everything with the world's first removable insert system.
The Removable Insert: Your Quality Control Breakthrough
Easy Removal
Simply pull out the insert - no tools needed
Camera Inspection
Use an endoscope or inspection camera to view inside the cavity
Verify & Document
Check insulation placement, look for mortar bridges, prove compliance
Reinsert & Done
Pop the insert back in - full functionality restored
What You Can Verify:
- Insulation is in place
- No mortar bridges present
- Cavity is clean and dry
- DPC/cavity tray functioning
- No blockages or debris
- Building regs compliance
The Competitive Advantage This Gives You:
🛡️ Protect Your Reputation
Prove to building control, warranty providers, and homeowners that everything is done correctly
📉 Reduce Callbacks
Catch issues before handover instead of getting calls years later
💰 Prevent Claims
Stop these cavity failures before they start
🏆 Marketing Gold
"Our homes feature inspectable cavity ventilation" - a genuine point of difference
What Makes Wind-Powered Active Ventilation Better Than Passive Vents?
Traditional vents just sit there and hope air flows through them. Active Vent harnesses the power of wind to actively pull moisture out - like a vacuum cleaner for your walls.
The Three Revolutionary Innovations:
Wind-Powered Suction
Uses the power of wind to create active suction that pulls moisture out
Inspectable Insert
World's first removable system for quality control and inspection
Cross-Ventilation
The only vent that exchanges air across the cavity, continuously replacing moisture-laden air with fresher air
| Feature | Active Vent | Traditional Passive Vents |
|---|---|---|
| Moisture Removal | ✓ Active wind-powered suction | ✗ Passive - hope air flows |
| Severe Weather Performance | ✓ Works even in storms | ✗ Blocks during rain |
| Quality Control | ✓ Fully inspectable | ✗ Black box - never know what's inside |
| Cavity Air Exchange | ✓ True cross-ventilation | ✗ Single-point drainage only |
| Cavity Moisture Removal | Active, continuous cavity ventilation | Minimal to none |
| Insulation Protection | ✓ Keeps insulation dry and effective | ✗ Lets insulation get wet and underperform |
| Claims Risk | ✓ Dramatically reduced | A leading superstructure defect type |
Why Should Developers Care About Cavity Wall Humidity?
Because wet walls are the hidden energy killer that leads to homeowner complaints, warranty claims, and damage to your reputation.
The Wet Insulation Problem
When moisture gets into cavity walls, it creates what's called interstitial damp (moisture trapped between layers of materials). This moisture soaks into insulation, dramatically reducing its effectiveness.
The Hidden Cost:
Scientific research shows that when insulation gets damp it can let through nearly twice the heat of dry insulation — quietly driving up heating bills.
Source: Hayrullin et al., Transportation Research Procedia, 2022
What This Means For You:
Homeowner Complaints
"My energy bills are sky-high!" - Even though you installed proper insulation, wet insulation doesn't work
SAP/EPC Issues
Predicted energy performance doesn't match reality when insulation gets wet
Warranty Claims
Damp-related issues trigger warranty calls and expensive remedial work
Reputation Damage
Unhappy homeowners leave bad reviews and tell others about their "cold, expensive-to-heat" home
Active Vent's Solution:
By continuously cross-ventilating the cavity and replacing moisture-laden air with fresher air, Active Vent keeps insulation dry and performing at its rated capacity. This means:
- Energy performance matches predictions - No nasty surprises for homeowners
- Homeowners get the energy performance they were promised - Happy customers = good reviews
- Fewer warranty claims - Protection against damp-related issues
- Better reputation - Build homes that actually perform as promised
What Results Can You Expect From Active Vent?
Built for Accountability
Active Vent's removable insert lets you inspect the cavity after the wall is closed up — checking for the rubble, mortar bridges and blocked weep holes that independent BRE/BEIS research identifies as leading causes of cavity-wall damp. Current cavity surveys don't require internal inspection of the cavity base, so this is a genuine quality-control gap the removable insert helps you close.
Why Inspection Matters:
In a BRE/BEIS survey of 390 failed brick cavity dwellings, 20% failed because water could not escape the cavity — caused by rubble or debris at its base. Being able to inspect and clear the cavity base directly addresses a documented cause of failure.
The Bottom Line:
- Fewer callbacks related to cavity dampness
- Faster building control sign-off
- Higher customer satisfaction scores
- Competitive marketing advantage
How Easy Is Active Vent To Install?
Installation is just as simple as traditional vents - but with the added benefit of quality control verification afterwards.
New Builds:
- 1 Place Active Vent between bricks during construction
- 2 Position 225mm apart at cavity tray locations
- 3 Ensure mortar is kept clear during bricklaying
- 4 Bonus: Inspect cavity with camera before final sign-off
Retrofit/Remedial:
- 1 Drill 65mm hole at cavity tray location
- 2 Insert Active Vent flush with wall surface
- 3 Mortar around edges to seal
- 4 Bonus: Inspect existing cavity condition before sealing
Technical Specifications:
Dimensions & Materials:
- Size: 65mm diameter x 230mm length
- Material: UV-resistant polypropylene
- Colors: Terracotta, natural, black, white, brown
- Eco option: 100% recycled material available
Performance & Compliance:
- Moisture control: Continuous cross-ventilation
- Weather resistance: All conditions
- Warranty: 10 years
- Compliance: Designed to support compliance with UK ventilation requirements and NHBC guidance
Stop Building With Yesterday's Technology
Join forward-thinking developers who are preventing claims, ensuring quality, and building better homes with Active Vent.
Need samples or technical specifications? Contact us for your development project.