What is the Future Homes Standard?
The 2025 Future Homes Standard (FHS) is a set of UK government regulations that detail requirements for energy efficiency and heating for new homes and non-domestic buildings.
The standards aim to ensure that all new homes built from 2025 onwards will produce 75-80% fewer carbon emissions than homes built under the previous regulations. The FHS prioritises low-carbon heating and building well-insulated, energy-efficient homes to reduce heat waste.
Part L and Part F of the Building Regulations were updated in June 2022 to prepare for the introduction of the Future Homes Standard. New requirements under Part F of the regulations focus on energy issues and providing ventilation in a property.
One element of the updated regulations was to increase the target for air tightness (<8m3/(h·m2)@50Pa). That means there’s an increasing need for good ventilation systems to ensure good Indoor Air Quality (IAQ). Whole house ventilation systems offer an effective solution to ensure good IAQ.
Why will new homes need better ventilation?
To meet the target of 75-80% fewer carbon emissions, new buildings must be increasingly airtight - preventing heat loss and improving energy efficiency.
But, as homes become more airtight, proper ventilation becomes even more important. Without it, these energy-efficient properties can face serious issues with:
Condensation and mould
Poor indoor air quality
Reduced comfort
What is whole-house ventilation?
Whole-house ventilation is a system that controls airflow throughout the entire building, rather than in a single room. It's designed to:
Deliver clean air throughout the property
Remove stale or moist air
Reduce the risk of condensation and damp
Types of whole-house ventilation
Mechanical Ventilation with Heat Recovery (MVHR)
Centralised Mechanical Extract Ventilation (MEV)
Decentralised Mechanical Extract Ventilation (dMEV)
Positive Input Ventilation (PIV) PIV
How does a whole-house ventilation system work?
Whole house ventilation systems can work by:
Drawing fresh air into the building to displace the moist or stale air (PIV)
Extracting air from multiple “wet” rooms to be replaced by clean air from outside (MEV, dMEV)
Or both combined (MVHR)
Mechanical Ventilation with Heat Recovery (MVHR)
Mechanical Ventilation with Heat Recovery (MVHR) systems offer whole-house ventilation systems with heat recovery.
They work by extracting air from wet rooms, like bathrooms and kitchens, while supplying fresh, filtered air into living spaces. Moist or stale air from the house is extracted via a heat exchanger, and the heat is transferred into the fresh air that’s introduced into the living spaces.
An effective MVHR system will recover up to 95% of the heat from the extracted air, minimising the energy needed to heat the building.
Air is extracted and supplied across the property via ducting whilst diffusers are fitted to the ceilings and can be adjusted to balance the system.
Benefits of MVHR
MVHR systems run continuously, extracting polluted air and introducing warm fresh air into the building.
They provide an excellent solution for meeting the Future Homes Standards around ventilation and energy efficiency.
MVHR systems provide the best Energy Performance Certificate (EPC) Ratings for serviced accommodation.
They can extract more polluted air when required - meeting the requirements of Part F, System 4 Building Regulations.
MVHR units can be installed in loft or cupboard spaces, so they are discrete and out of sight.
MVHR systems are ideal for
New build housing
Social housing
Full-house renovations
Single-room MVHR systems
Single-room MVHR systems can provide a solution in locations where it’s not practical or economical to install a whole-house system. As the name suggests, they operate in the same way as a whole-house heat recovery system. The only difference is that they're designed to work in individual rooms. A heat exchanger will extract the heat from the air and use this to warm clean air being drawn into the relevant room.
Benefits of single-room MVHR systems
Retain up to 93% of the heat that would normally be wasted by a conventional extractor fan, providing huge heating cost benefits.
Provide higher levels of Indoor Air Quality (IAQ) by filtering the air and removing pollutants.
Effective for preventing mould and condensation
Simple to install and silent to run.
Check out our range of single room heat recovery products.
Centralised Mechanical Extract Ventilation (MEV)
Whole-house Mechanical Extract Ventilation (MEV) systems use a central unit to extract moist air from wet rooms, providing continuous ventilation to the rest of the house. This means there’s no need for individual extractor fans in the wet rooms. MEV systems don’t recover heat from the moist air so don’t need a heat exchanger or ducts to supply replacement air.
Some MEV units include advanced features such as:
Humidity sensors: These increase fan speed in proportion to humidity levels, saving energy and reducing noise.
CO₂ sensors: These sensors increase ventilation when there are more people in the house to ensure the best indoor air quality.
Benefits of MEV
Improved indoor air quality
Prevents condensation and mould
Suitable for homes with high air leakage
Less ducting is required compared to MVHR
Quieter operation than extractor fans
MEV systems are ideal for
New build housing
Full house renovations
Decentralised Mechanical Extract Ventilation (dMEV)
A decentralised Mechanical Extract Ventilation (dMEV) system consists of a continuous mechanical extract ventilation system that removes moist or polluted air from each wet room in the property.
dMEV systems operate continuously so they are more energy efficient than on/off ventilation systems. They also provide quieter ventilation than standard extractor fans.
Many dMEV units come with variable-speed fans and sensors that monitor indoor air quality and improve airtightness. This also helps with energy saving.
Benefits of Decentralised Mechanical Extract Ventilation (dMEV)
Continuously extract moist and polluted air to improve indoor air quality
Simple to install and maintain
Existing extractor fan ducting can often be used, so they’re simple to retrofit
Quieter than standard extractor fans
dMEV systems are ideal for
Retrofit
Single room renovations
New build homes
Positive Input Ventilation (PIV) or PPV
Positive Input Ventilation (PIV), also known as Positive Pressure Ventilation (PPV) is another form of whole-house ventilation. PIV and PPV systems dilute and displace unhealthy air in buildings, replacing it with clean, fresh and filtered air.
They work by drawing fresh air in through a unit generally installed in the loft. This clean air is filtered and diffused at ceiling level, creating positive pressure that forces the stale and unhealthy air out of the home.
Benefits of Positive Input Ventilation (PIV) or Positive Pressure Ventilation (PPV)
Provides fresh filtered air into the home
Cost-effective way of removing condensation
Proven to prevent mould
PIV units can be installed in any residential property
Produce almost no noise, even when running at full speed
Low running costs
PIV/PPV systems are ideal for
Retrofitting in homes to improve indoor air quality.
Check out our range of PIV products.
Why have whole-house ventilation?
Reducing draughts and improving the airtightness of a home can make a huge difference to the amount of energy needed to keep it warm. But homes also need to be ventilated to reduce issues such as condensation, mould and poor air quality.
Traditional ventilation such as opening windows and using extractor fans can be energy inefficient and doesn’t offer any control over the quality of air that circulates around the home. Whole-house ventilation systems offer far more reliable control as clean air is more evenly distributed throughout.
Because they reduce indoor air pollutants, whole-house ventilation systems can offer some carbon monoxide protection. But they are not a substitute for proper carbon monoxide detectors.
For allergy sufferers, systems with good filtration, like MVHR, can help reduce airborne allergens including pollen, and so reduce the risk of allergic reactions or asthma.
What are the benefits of whole-house ventilation?
Improved indoor air quality
Reduced risk of condensation and mould
Energy efficiency, especially with heat recovery systems
Compliance with Future Homes Standard and Building Regulations
How much does a whole-house ventilation system cost?
The cost of whole-house ventilation systems depends on the type of system and the size of the property.
MVHR systems tend to be the most expensive but offer the highest energy savings
MEV and dMEV systems are generally less expensive but don't provide heat
PIV systems are often the most cost-effective, especially for retrofit projects
When to use whole-house ventilation
You should consider whole-house ventilation systems for:
New builds aiming to meet Future Homes Standard
Properties with a high level of air-tightness
Homes with persistent condensation or mould issues
Retrofit projects aiming to improve energy efficiency and indoor air quality
What to consider when installing whole-house ventilation
When installing a whole-house ventilation system you need to:
Choose the appropriate system based on the property type and client needs
Specify the correct size system for the property
Plan ducting routes carefully to maximise efficiency
Balance the system to ensure proper airflow in all rooms
Consider noise levels, especially for units installed near living spaces
Ensure compliance with Building Regulations, particularly Part F and L
Guide Summary
As construction demands more energy-efficient and airtight buildings, whole-house ventilation systems will become increasingly important. Understanding these systems and how they work will be crucial for meeting regulatory requirements and providing solutions for your customers.