Can You Install a Log Burner in a Passive House?

Transform your airtight haven into a warm retreat! Discover how to safely incorporate a traditional log burner into your energy-efficient home.

In the world of sustainable living, Passive Houses have gained immense popularity for their energy-efficient design and minimal environmental impact.

As more homeowners embrace the concept of green living, questions arise about the compatibility of traditional heating methods, such as log burners, with Passive Houses.

Estimated reading time: 7 minutes

Understanding Log Burners

Log burners, also known as wood-burning stoves, have been a traditional heating solution for centuries. These appliances burn wood logs to generate heat, providing warmth and a cosy atmosphere in homes.

However, the question arises: can they seamlessly integrate into the modern concept of Passive Houses?

Key Features of Passive Houses

A rising trend from PassivHaus to AECB Carbonlite sees a surge in the creation of ‘hermetically sealed’ houses.

Crafting a home with airtight qualities not only magnifies energy efficiency but also substantially augments property valuation.

Unveiling the Airtight Concept: For those unacquainted with avant-garde construction methodologies like PassivHaus and MVHR Systems, the notion of fabricating an airtight dwelling might seem eccentric, perhaps perilous.

The fundamental tenet of an airtight dwelling revolves around establishing an impermeable air barrier encompassing the entire structure, encompassing walls, ceilings, and floors.

Under frameworks like PassivHaus, a comprehensive strategy prevails, emphasising insulation maximisation through:

• Precision-oriented design modeling via the Passive House Planning Package (PHPP).
• Elevated levels of insulation.
• Windows of unparalleled performance, featuring insulated frames and robust construction replete with high-quality seals.
• Construction eliminating thermal bridges, those zones in a structure with heightened heat transfer compared to their surroundings.
• A mechanical ventilation system adept at recuperating substantial heat.

These components amalgamate to form a residence meticulously regulating the ebb and flow of heat within its confines.

Types of Airtight Homes

Divergent Standards for Airtight Homes: Two principal benchmarks delineate when a dwelling achieves airtight status:

1. PassivHaus: Originating in Germany, this standard epitomizes homes boasting minimal energy consumption. Meeting stringent building criteria defines a property as PassivHaus, making it clear that not every airtight home is a PassivHaus, but every PassivHaus qualifies as an airtight dwelling.
2. AECB Carbonlite: As the UK’s counterpart to PassivHaus, Carbonlite, established by the Association for Environment Conscious Building (AECB), outlines measures to establish and sustain structures characterized by exceptionally low energy consumption and CO2 emissions.

Can a log burner be used in an airtight house?

The short answer is yes! However, it has to be the right type of log burner, installed in the correct way.

Navigating Log Burner Installation in Airtight Dwellings: Installing a log burner in an airtight home markedly differs from the conventional process in a standard abode.

The primary divergence stems from the quandary of air permeability.

Existing UK Building Regulations mandate a maximum air permeability of 10 m3h-1m-2 for homes, facilitating adequate air intake for log burners to function.

Contrarily, airtight homes, by design, do not permit such airflow, necessitating specific measures during installation to guarantee optimal log burner performance.

Key Considerations

Key Considerations for Log Burner Installation in Airtight Homes:

Heat Output

The thermal output of the log burner assumes paramount significance. Higher output mandates increased oxygen consumption.

Fortunately, due to the high thermal efficiency of airtight homes, a log burner within a PassivHaus or AECB Carbonlite abode typically requires a modest 1 to 3kW output.

Naturally, exceptions arise, especially in larger airtight residences, contingent upon factors such as home orientation, sunlight exposure, and supplemental heat sources like solar panels.

Combustion Air Supply

For a log burner to burn properly it will require sufficient air supply. Drawing combustion air directly from the room is undesirable.

Instead, a log burner in an airtight home must access fresh air outside via a dedicated pipe or tube connected directly to its body, passing through an external wall – a setup known as direct air supply or external air.

This is known as a Direct Air Supply or External Air Kit which is a 80mm or 100mm pipe that is connected to the rear of the log burner.

These are generally available as an add-on with the majority of stoves on the market, however not all will be compatible.

DIBt Tested Log Burners

When selecting a log burner for an airtight home, consideration must be given to whether it has undergone the DIBt test.

Originating in Germany, this test assesses a log burner’s room seal effectiveness, especially the airtightness of the door.

A DIBt-tested log burner, equipped with direct air supply, attains almost complete room sealing.

While DIBt testing isn’t obligatory, it holds significance if the airtight home incorporates MVHR (Mechanical Ventilation Heat Recovery) technology.

The best Dibt tested Wood Burning Stove

The SCAN 83 stands out as one of Denmark’s most robust stove designs, spearheaded by the talented design team at Harrit & Sorensen.

The emphasis on aesthetics and functionality is evident in its simplistic design and efficient clean burn. Each aspect of the stove has been meticulously considered, showcasing features like the gracefully curved glass door equipped with a soft close and an automatic lock system.

Shop SCAN 83 Range here

Or speak to one of our professionals on 0118 970 1717 or email info@bonfire.co.uk and we’ll be able to find a log burner suitable for your property.

Pressure Testing

During the final stages of airtight home construction, a pressure test becomes likely. Depending on local regulations, log burner installation might precede this test.

Tip: Check with your nearby building control department to determine whether they require the installation of your log burner before conducting a pressure test.

Blocking all building ‘holes,’ including the direct air supply to the log burner, is standard. Occasional exceptions may allow minimal air leakage, generally deemed inconsequential to airtight home classification.

Local building control departments should be consulted regarding log burner installation timing in relation to pressure testing.

MVHR Impact

Mechanical Ventilation Heat Recovery (MVHR) technology, employed for fresh air infusion while conserving existing heating energy, is prevalent in airtight homes.

However, MVHR can induce negative pressure in a room, potentially impeding log burner functionality.

Opting for a log burner with direct air supply becomes imperative in MVHR-equipped airtight homes, ensuring consistent functionality irrespective of internal air pressure fluctuations.

DIBt-tested log burners might prove advantageous in MVHR-influenced properties.

Air Vents

Current Building Regulations necessitate the installation of a non-closable air vent in the external wall of a room housing solid fuel-burning appliances like log burners.

In airtight homes, this requirement challenges the very concept of airtightness. To address this, revisions to the BS 8303 standard acknowledge the surge in airtight dwellings.

According to HETAS, overseeing log burner installation regulations in the UK, BS 8303 permits log burner installation sans a non-closable vent under certain conditions:

1. Carbon Monoxide Detector: Irrespective of direct air supply and smoke venting, a carbon monoxide detector in the room with the log burner is imperative for safety.
2. HETAS-Qualified Installation: Consistent across these considerations is the vital aspect of proficient log burner installation in an airtight home. Ensuring the correct log burner size, direct air supply, and compliance with MVHR and BS 8303 specifics underscores the significance of engaging a HETAS-qualified installer. Many local authorities mandate this choice, as HETAS installers possess the expertise to navigate these complexities, garnering approval from local planning authorities.

Navigating the labyrinth of log burner integration in an airtight abode entails meticulous attention to detail. Leveraging the expertise of a HETAS-qualified installer becomes not just a suggestion but a prudent imperative for a seamless and approved log burner installation in an airtight home.

Prioritise log burners subjected to the DIBt test, evaluating room seal effectiveness and airtightness. DIBt tested burners, often 100% room sealed, can withstand air pressure changes associated with Mechanical Ventilation Heat Recovery (MVHR) technology in airtight homes.