Log Burner Ventilation: What Are The Requirements?

A log burner brings that warm, crackling glow to any space — but it’s important to enjoy this cosy treat safely.

Ventilation is an important aspect of log burner ownership that cannot be overlooked. An air vent keeps your home or business free from smoke and harmful gases, and also maintains the effectiveness and efficiency of your burner.

But not every home needs ventilation for a log burner — there are some exceptions.

In this article, we’ll explore why ventilation is important, and how to find out if your home requires ventilation for a log-burning stove.

Why is ventilation important for log burners?

Because log burners burn fossil fuel, they generate gases and fumes that need to escape. To prevent harmful gases from filling up inside your home, an air vent will sometimes be needed to help channel these harmful gases to the outside of your property through the chimney. 

Ventilation is also essential for the burning process, delivering fresh oxygen from the outdoors into the room the stove is in to help fuel the fire.

However, some homes have ventilation already present and won’t require a vent to be added, while others will not have enough ventilation and will require assistance. So how do you tell what your property needs?

Does my home need ventilation for a log burner?

Not every home requires a ventilation system to be installed. It all depends on the air permeability of your home which is a measure of how airtight your property is. 

Below are general guidelines for the requirements of the three main types of properties based on when they were built and whether they were modified.

• Houses constructed after 2008: The majority of homes constructed after 2008 are built to a different air tightness quality than prior to 2008. This means that less outside air can enter, which may require you to have ventilation installed when fitting a log-burning stove.
• Houses built before 2008 with no modifications: If your home was constructed before 2008 and you have not upgraded it, then you most likely will not require an in-built ventilation system, provided the log burner’s output remains below 5kW. If your chosen burner has an output above 5kW, then you might require a ventilator.
• Houses constructed prior to 2008 that have been upgraded: Some homes built prior to 2008 may have undergone upgrades to elevate them to contemporary standards of air tightness, such as extra window glazing or home insulation. If this is the case, your property will therefore likely require an air vent for a log burner.

Please note that the above advice is only a guideline and so you must seek advice based on your individual case. The best route is to get your house’s air permeability tested and go from there.

If your home does require a ventilation system installed, it will need to be completed by a HETAS-accredited installer such as Enviro-Flame.

How much ventilation will I need?

Once you’ve checked with a professional on how air-permeable your home is, and therefore whether you’ll need ventilation in the first place, it’s a good idea to seek advice on how much ventilation you will need. 

This will depend on the permeability rating of your home and the power output of your chosen log burner. Some properties will require a small opening while others will need a much larger air vent. 

Typically, a 5kW stove in an airtight home will require a vent 2750mm2, for each kW over, an additional 550mm2 of ventilation will be required.  If it is an older property of poor air tightness, most stoves up to 5kW do not normally require additional ventilation.

Always check with a professional

When purchasing a new log burner, always consult with your chosen log burner provider as they will be able to tell you whether you need ventilation at all, and then will recommend ventilation that’s right for your property depending on the burner you choose.

If you choose to work with an all-service company, such as Enviro-Flame, they will also be able to carry out the work to install an air vent too.

Even once ventilation is installed to allow your stove and flue to channel away any fumes, you will still need to install a carbon monoxide alarm for extra safety, which is a Building Regulation Requirement when burning solid fuel. This is a recommendation for all homes regardless of whether you have a log burner or not.

Here at Enviro-Flame, we’re a leading HETAS-accredited supplier and installer of log burners for London and Wimbledon. With a huge range of makes and models to choose from, our HETAS and Gas Safe fitters ensure that whatever you choose, it will be installed safely and with the correct ventilation for your needs. Simply get in touch to discover more, or book a visit to our impressive showroom to see our options first-hand.