Do you want chimney breast in your new build property?

Don’t worry, we can install a twin wall chimney system and a false chimney breast if required. Adding a false chimney breast to a new build property adds a lot of character to a room and also creates alcoves for shelves etc. Below is a simple guide on how we create false chimney breasts together with a twin wall chimney and wood burner installation.

What’s is a Twin wall Chimney?

A twin wall chimney is a double skinned insulated pipe used to create a chimney in properties without a traditional brick chimney. We can advise on wether to use a internal system through the ceilings of a house exiting through a roof or externally through the external wall up the side of a property.

A simple guide to creating a false chimney for a woodburner in a new build property.


Step One: Buying the right stove and positioning advice

Consider the position of the stove in your room. For chimney breast construction we commonly install in the center of a wall or for freestanding stoves we often install the corner. The corner is often a good option for free standing stoves as the space normally isn’t obstructing a walkway.

Important: You will need to consider combustible items near your wood burner including plug sockets, wooden or plastic window seals, curtains and also plasterboard walls. Many wood burners have a 300 mm plus distance to combustibles from the side and rear of the stove unless using a convection stove, which can have a mere 150mm to combustibles from sides and 100mm to rear. Click Here

False Chimney Breast Construction New Build

Note: Some cheaper cylinder free standing stoves require a 6″ diameter flue outlet as opposed to smaller 5″ system commonly used. You may save money on the stove but then pay a premium for a larger diameter chimney system.

Step Two: Installing twinwall chimney system

In this example we positioned the wood burner centrally on the slate hearth and calculated the position of the twin wall chimney pipe to exit through the wall. We prefer to use single skin vitreous pipe off the top of the wood burner for aesthetics and so replaced a section of plasterboard at rear of the recess with fire board together with sides of the chamber and front legs for the chimney breast in accordance with HETAS and building regulations.

We continued to install the twin wall chimney system up adjacent to the property, finishing the installation with an anti downdraft cowl, which helps to protect against wind.

Note: We always use a professional powder black chimney system, opposed to the stainless steel system that can stain and age quickly.

Twinwall chimney and chimney breast for new build property

Step Three: False chimney breast constuction in a new build property

Once the twin wall system is installed we remove the wood burner and focus on building the chimney breast using stainless steel stud work called U stud and C Stud which is available from most building merchants. I like a recess/chamber height of at least 900 mm x 800 mm width providing an overall width of the chimney breast to approximately 1400 mm.

The chamber is framed with fire board due to proximity to the wood burner, whilst the sides and top section of the chimney breast is plasterboard. The twin wall chimney system we used has a 5″ diameter inside with a 7″ diameter externally and only requires a 50 mm distance to combustibles. You must use twin wall chimney system and wall sleeve when exiting through a external wall.

Note: Consider supports areas within frame structure for hanging mantels, mirrors or pictures. We use ceramic fire potective mantels in order to be positioned close to the wood burner.

False Chimney Breast Constuction in New Build Property

Step Four:  Room Ventilation, Fire boarding and Plastering

HETAS and building regulations state we have to allow for additional ventilation in a room due to the property being built after 2008, even for a 5kw stove. Therefore, we cored a 4″ hole through the wall behind the stove directly in line with the stove air intake to reduce potential draft. A cover plate was used on the inside with a anti insect filter externally.

Fire board, plasterboard and scrim tape joins before plastering. Leave to dry for 4-5 days before painting.

We installed a Ecosy Panoramic multi fuel wood burner using this external twin wall chimney system.

Note: Some types of fire board require several coats of PVA glue before plastering as very porous material or the plaster will dry too quickly and crack.

Room Ventilation, Fire boarding and Plastering

Let us build a false chimney breast and install a wood burner for you,

Call us on 07715 104 420 for a free no-obligation survey and quote if you live in the Somerset Area.

Note: Always take advice from a HETAS wood burner installer before attempting to do this yourself.