Elta MORI WMF100 Sub Floor Ventilation Fan Bundle – Supply AIR IN + Extract AIR OUT (Mains Powered)
Complete Mains-Powered Subfloor Ventilation System for Damp, Humidity, Condensation and Airflow Control
The Elta MORI WMF100 Sub Floor Ventilation Fan Bundle provides a practical and energy-efficient solution for improving ventilation beneath suspended timber floors. Combining one Supply Fan to push fresh air INTO the subfloor void with one Extract Fan to pull stale, humid air OUT, this complete mains-powered package is designed to establish continuous mechanical airflow beneath the property.
Unlike traditional passive air bricks, which rely on natural air movement, the Elta MORI WMF100 fan bundle actively moves air through the underfloor space, helping to reduce excess humidity, condensation and moisture accumulation in areas where natural ventilation may be insufficient.
Poor subfloor ventilation can contribute to stagnant air, musty odours, excessive moisture and conditions that encourage mould growth and timber decay. By introducing fresh air at one point and extracting stale air at another, the two fans work together to promote more consistent ventilation throughout the floor void.
The system is particularly suitable for older properties, suspended timber floor constructions, refurbishment projects and buildings where existing air bricks struggle to provide effective cross-ventilation.
The bundle can also form part of an appropriately designed subfloor radon management strategy, where mechanical ventilation is recommended following a professional assessment.
At £465.99 including VAT, this package combines both complementary Elta MORI ventilation models in one convenient solution.
What’s Included in the Elta MORI WMF100 Subfloor Ventilation Bundle?
The bundle contains two complementary mains-powered ventilation fans:
- 1 x Elta MORI WMF100 Supply Fan – Pushes AIR IN: Mechanically introduces fresh external air into the subfloor void to encourage air circulation beneath suspended floors.
- 1 x Elta MORI WMF100 Extract Fan – Pulls AIR OUT: Mechanically removes stale, humid air from the subfloor space and discharges it outdoors.
Together, the two fans provide a coordinated supply-and-extract ventilation arrangement.
Both units are designed for low-energy operation and feature adjustable low-running and boost ventilation speeds.
Key Features & Benefits
- Complete Supply and Extract Ventilation Bundle – Includes one fan to introduce external air and another to remove stale air from the subfloor void.
- Improves Subfloor Air Circulation – Helps establish a more consistent airflow route beneath suspended timber floors.
- Helps Reduce Excess Humidity – Supports the removal and replacement of moisture-laden air where outdoor and building conditions are suitable.
- Helps Manage Condensation – Improved ventilation can reduce conditions that encourage condensation beneath floors.
- Helps Protect Suspended Timber Floors – Reducing persistent moisture can make conditions less favourable for fungal growth and timber deterioration.
- Low-Energy Fan Technology – Designed for economical, continuous mechanical ventilation.
- Adjustable Low and Boost Speeds – Allows ventilation settings to be adapted to the needs of the installation.
- Weatherproof Fan Construction – Suitable for appropriate external-facing subfloor ventilation arrangements.
- Ideal for Difficult-to-Ventilate Spaces – Particularly useful where passive air bricks alone may not provide sufficient airflow.
- Potential Radon Management Application – May be incorporated into a professionally designed subfloor radon mitigation system.
How Does the Elta MORI Supply and Extract Ventilation Bundle Work?
The Elta MORI WMF100 bundle uses two fans operating in complementary directions to encourage airflow through the subfloor space.
Step 1 – Supply Fan Pushes Fresh Air IN
The WMF100 Supply Fan draws external air into the building’s subfloor void.
This helps introduce replacement air beneath the suspended floor, particularly where natural ventilation openings are insufficient.
Step 2 – Air Moves Through the Subfloor Void
As replacement air enters, it can move through the underfloor space towards suitable extraction points.
This movement helps reduce stagnant air and encourages ventilation across the floor void.
Correct positioning is important, particularly where internal sleeper walls or other obstructions restrict airflow.
Step 3 – Extract Fan Pulls Stale Air OUT
The WMF100 Extract Fan removes air from the subfloor void and discharges it outdoors.
This can help remove moisture-laden air and promote continuous air exchange beneath the building.
The result is a coordinated mechanical subfloor ventilation arrangement, providing both an active air supply and an active extraction point.
Actual airflow distribution and moisture-control performance depend on the building layout, ventilation openings, fan settings and outdoor conditions.
Why Use Both Supply and Extract Fans Together?
Installing both a supply fan and an extract fan offers a more coordinated approach to subfloor ventilation than relying on an individual fan alone.
A Supply Fan introduces replacement air, while an Extract Fan provides a mechanical outlet for existing air.
When correctly positioned, these complementary functions can encourage airflow across a larger proportion of the subfloor void.
This arrangement can be particularly useful in properties with:
- Long or narrow subfloor spaces
- Restricted natural cross-ventilation
- Poorly positioned air bricks
- Internal sleeper walls affecting airflow
- Areas where air movement is inconsistent
- Persistent high humidity beneath suspended floors
- Large floor voids requiring more controlled ventilation
The fan positions, available airflow pathways and operating settings must be chosen to suit the individual property.
Subfloor Ventilation and Suspended Timber Floor Protection
Suspended timber floors rely on suitable ventilation beneath the floor structure to help manage moisture.
Inadequate subfloor airflow can contribute to increased humidity, condensation and stagnant air.
Over time, persistent damp conditions can increase the risk of:
- Timber deterioration
- Fungal growth
- Wet rot
- Musty odours
- Condensation beneath floorboards
- Moisture damage to vulnerable building materials
- Poor air movement within the subfloor void
The Elta MORI WMF100 Supply and Extract Fan Bundle helps improve ventilation by introducing external air and removing existing subfloor air.
This can help make conditions less favourable for moisture-related deterioration when the system is correctly designed and installed.
However, ventilation does not replace the need to investigate leaking pipes, standing water, defective drainage or other causes of excessive dampness.
Ideal Applications
The Elta MORI WMF100 Sub Floor Ventilation Bundle is suitable for consideration in:
- Houses with suspended timber floors
- Older properties with limited subfloor ventilation
- Properties with inadequate natural airflow through air bricks
- Damp or humid subfloor voids
- Buildings experiencing musty smells beneath flooring
- Renovation and refurbishment projects
- Subfloor spaces with restricted cross-ventilation
- Properties requiring continuous mechanical underfloor ventilation
- Coordinated supply-and-extract ventilation installations
- Suitable professionally designed radon management systems
The appropriate installation will depend on the size, layout and construction of the property.
Low-Energy, Continuous Subfloor Ventilation
Both Elta MORI WMF100 ventilation fans incorporate low-energy motor technology designed for continuous operation.
The individual fan information quotes typical electricity running costs of under £9 per year per fan under the stated low-speed operating assumptions.
As this bundle contains two fans, the electricity consumption of both units must be taken into account.
Actual operating costs depend on the chosen speeds, power consumption, running hours and electricity tariff.
The adjustable low-running settings allow ventilation to operate continuously at a selected level, while boost operation provides additional airflow when required.
This flexibility makes the bundle suitable for installations where ventilation demands may vary.
Mechanical Ventilation vs Traditional Air Bricks
Traditional air bricks provide passive ventilation beneath suspended floors.
Their effectiveness depends on natural air movement, wind conditions, pressure differences and the arrangement of ventilation openings.
In some properties, passive ventilation is adequate.
However, where existing air bricks are blocked, poorly positioned or unable to provide consistent airflow, mechanical ventilation may offer additional benefits.
The Elta MORI WMF100 bundle provides active airflow rather than relying entirely on natural ventilation.
Benefits of mechanical subfloor ventilation include:
- More controlled airflow
- Continuous operation at selected fan speeds
- Additional ventilation where passive airflow is restricted
- Active introduction and removal of air
- Improved opportunities for airflow management through difficult subfloor layouts
Existing air bricks may still form an important part of the overall ventilation arrangement and should not automatically be blocked or removed.
Installation and Positioning Considerations
Correct installation is essential to achieving effective subfloor ventilation.
The Supply Fan and Extract Fan should be positioned to encourage airflow through the intended subfloor space, rather than allowing air to enter and leave through a short, ineffective route.
1. Assess Existing Ventilation
Check the location and condition of existing air bricks and identify any obstructions or areas with limited airflow.
2. Plan the Airflow Route
Position the Supply Fan to introduce external air and the Extract Fan to remove air from an appropriate location.
Aim to establish airflow through the areas requiring ventilation.
3. Consider the Subfloor Layout
Internal walls, compartments and restricted openings can affect how air moves beneath the floor.
These features may require additional assessment or airflow provisions.
4. Identify Moisture Sources
Investigate plumbing leaks, water ingress, standing water, groundwater and other sources of excess moisture before relying on mechanical ventilation.
5. Provide Suitable Mains Electrical Connections
Both fans are mains-powered electrical appliances and must be installed in accordance with their instructions and applicable electrical safety requirements.
6. Allow for Maintenance
Ensure both units remain accessible for inspection and any recommended maintenance.
7. Check Operating Performance
Once installed, confirm that both fans are operating in the intended directions and that suitable airflow is being achieved.
Where moisture or radon reduction is the objective, appropriate measurements should be used to assess the system’s effectiveness.
Can This Subfloor Ventilation Bundle Help With Radon Gas?
Radon is a naturally occurring radioactive gas that can enter buildings from the ground.
In certain buildings, mechanical subfloor ventilation can form part of a radon mitigation strategy.
The Elta MORI WMF100 Supply and Extract Fan Bundle may be suitable for consideration within a professionally designed system where subfloor ventilation has been identified as an appropriate approach.
However, the balance between supply and extraction is important because airflow direction and pressure differences can influence radon movement.
A standard supply-and-extract arrangement should not automatically be assumed to provide effective radon reduction.
Where radon is a concern, testing, specialist assessment, correct system design and post-installation measurements are important.
Frequently Asked Questions
What is included in the Elta MORI WMF100 ventilation bundle?
The bundle includes one Elta MORI WMF100 Supply Fan and one Elta MORI WMF100 Extract Fan. Together, they provide complementary air supply and extraction for suitable subfloor ventilation installations.
Which fan pushes air in and which pulls air out?
The Supply Fan pushes fresh external air INTO the subfloor void, while the Extract Fan pulls existing air OUT.
Can both fans run continuously?
The WMF100 fans are designed for low-energy mechanical ventilation and feature adjustable low-running and boost settings. Continuous operation should follow the manufacturer’s installation requirements.
Will the bundle help reduce damp beneath suspended floors?
Where inadequate ventilation contributes to high humidity, the bundle can help improve airflow and moisture management. It will not repair leaks, standing water or other underlying moisture problems.
Is this bundle better than using a single subfloor fan?
A correctly designed supply-and-extract system can provide a more controlled airflow arrangement than a single fan. However, the best configuration depends on the property’s layout, existing ventilation and moisture conditions.
How much electricity does the Elta MORI WMF100 bundle use?
The fans are designed for low-energy operation. The supplied product information quotes typical costs of under £9 per year for each fan under specified low-speed conditions. Actual combined running costs depend on operating speeds and electricity prices.
Can the bundle help prevent timber rot?
Improved ventilation can help reduce excessive moisture conditions associated with timber deterioration. It cannot reverse existing rot or replace necessary timber repairs and moisture-source treatment.
Can the fans replace existing air bricks?
Not necessarily. Existing ventilation openings may remain necessary to provide suitable airflow through the subfloor space. The correct arrangement depends on the building.
Is the bundle suitable for older properties?
Yes, it can be considered for older properties with suspended timber floors and inadequate natural subfloor ventilation, subject to an appropriate assessment.
Can this system reduce radon levels?
Mechanical subfloor ventilation can be part of a radon reduction strategy in suitable properties. However, the arrangement must be correctly designed and tested; the bundle is not a guaranteed standalone radon remedy.
Do I need an electrician to install the fans?
Both units are mains powered. Electrical installation must be completed safely by a suitably competent person and comply with applicable electrical regulations.
What is the price of the Elta MORI WMF100 Subfloor Ventilation Bundle?
The Elta MORI WMF100 Supply and Extract Fan Bundle is £465.99 including VAT, providing both complementary ventilation fans in one package.
Why Choose the Elta MORI WMF100 Sub Floor Ventilation Fan Bundle?
The Elta MORI WMF100 Sub Floor Ventilation Fan Bundle provides a practical solution for improving air movement beneath suspended timber floors where passive ventilation may be inadequate.
By combining one mains-powered Supply Fan with one matching Extract Fan, the package offers a coordinated approach to introducing replacement air and removing stale subfloor air.
Its low-energy technology, adjustable operating speeds and weatherproof fan construction make it a useful option for suitable residential ventilation projects.
Whether you’re renovating an older property, addressing poor underfloor airflow or planning a mechanical ventilation installation, this bundle brings together both complementary ventilation models.
Elta MORI WMF100 Supply + Extract Bundle – £465.99 Inc VAT
SUPPLY FAN – PUSHES AIR IN
EXTRACT FAN – PULLS AIR OUT
Important: Mechanical subfloor ventilation should be designed around the property’s construction, airflow requirements and moisture conditions. It is not a guaranteed cure for rising damp, penetrating damp, existing timber rot or radon problems.
