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It can be easy and economical to build a new chimney during construction of a house or extension, or add one to the inside or outside of an existing property. Topstak offers a choice of high quality systems to suit traditional or modern appearances.

We also specialise in supplying chimney systems for barn conversions, where Planning Departments often demand a metal chimney above the roof.

Topstak are premier stockists for leading chimney manufacturers including Schiedel Rite Vent, Isokern, Hanson Red Bank, Pennine, Euro cowl, Brewer and many others. We hold large stocks and offer competitive prices with next day delivery.

As each installation can be very different we offer a TECHNICAL INFORMATION SERVICE for all our products and can provide typical layout drawings for installing new chimneys for use with stoves, boilers or open fires, including large inglenook fireplaces. {create link to Inglenook page}

We can help with ideas and answers for almost any situation, and are backed over 35 years practical experience of designing chimney installations. Our friendly technical sales team are also HETAS registered, so you can be sure of a professional and enthusiastic service.

The following systems are the most popular systems used for installing a new chimney are as follows, and the choice really depends on the type of appliance and fuel being used.

·       Metal chimney systems {create link to same heading below}, which is quick to fit and ideal for installation into an existing property or barn conversion for use a wood or multi-fuel burning stove, or inset fire. There are also specialised metal chimney systems for use with gas or oil fired appliances.

·       Chimney blocks {create link to same heading below}, are designed for quick block on block installation that incorporate a flue liner and are a great way to build a new chimney that can be rendered or clad to create a traditional look.

·       Flue liners {create link to same heading below}, are made from clay or concrete and then surrounded by brick, building block or stone to create what is usually called a “traditional chimney”. We always recommend the pumice concrete flue liners for use with wood burning stoves or open fires. We also supply a comprehensive range of clay chimney pots{create link to Red Bank Chimney pots brochure, rain caps and cowls.

More information about these systems is given below.

Metal Chimney Systems

Metal chimney systems provide a quick and economical way to install a chimney in a new or existing property. They feature a simple push fit or twist lock-jointing arrangement for rapid installation and have a comprehensive choice of pipe sections, bends and fittings.

Our ICS insulated metal chimney, often called “Class 1” is used for wood or multi-fuel burning stoves and open fires. It can also be used with oil or gas burning appliances. An insulated oil or K vent system is limited to use with certain types of oil-fired appliances and most gas appliances. A Twin wall or gas vent system is limited to use with gas fired appliances and certain types of oil burning appliances.

The ICS Insulated Metal Chimney System

This system made to a very high quality standard is considered to be one of the best and most robust CE marked systems available. It has passed stringent performance testing and is featured in the HETAS list of approved chimney systems

The chimney sections have simple “push fit” jointing for easy assembly. The high quality stainless steel inner liner is surrounded by insulation and a stainless steel outer casing to give maximum performance and durability.

It is suitable for use with solid fuel, coal or wood burning heating appliances, including open fires and there is a comprehensive choice of pipe sections, bends and fittings to suit almost any arrangement.

The ICS system is ideal for use in barn conversions and for installation with the wide range of modern and contemporary stoves distributed by Topstak.

The chimney sections and fittings have a standard “shiny” stainless steel appearance, and we can supply alternative finishes such as powder coated matt black, which is a good way to get the chimney above a roof to blend in with roof slates.

We carry large stocks of the standard diameters of 130mm (5 inch), 150mm (6 inch), 180mm (7 inch) and 200mm (8 inch). Other diameters up to 600mm (24 inch) are also available.

The ICS system can also be used above a standard brick built fireplace or with a precast concrete firechest to suit solid fuel and also decorative flame effect gas open fires.

We can help with ideas and answers for almost any situation, so please call us. Our friendly technical sales team are also HETAS registered, so you can be sure of a professional and enthusiastic service.

It is really important to make a good connection between a wood burning stove and chimney using a single wall “connecting flue pipe.

We stock the 1mm thick 316 grade Prima Plus stainless steel in the standard 130, 150, 180 and 200mm diameters.

It is made to a really high standard with a choice of straight and telescopic pipes as well as various bends. They have a generous push fit spigot and socket connection with an optional locking band.

The flue pipes can be easily sprayed on site with the same paint as the stove being fitted.
We also stock vitreous enamelled flue pipes.

Metal chimneys for oil or gas appliances

B Vent – Twin Wall Gas Vent
This system is specifically designed for use with gas fires and consists of aluminium inner liner surrounded by an insulating airspace and zalutite metal outer casing. It is cost effective answer for installing a chimney above a gas fire, this system is also suitable for connecting a gas flue block system to a ridge vent terminal.

K Vent
This is a twin wall insulated chimney system specifically designed for use with domestic oil (i.e. Kerosene or 28 sec. oil) burning appliances up to a maximum input rating of 60kW. The system is also suitable as a higher specification chimney for gas burning fires. The stainless steel inner liner is surrounded by insulation and a zalutite metal outer casing.

We can help with ideas and answers for almost any situation, so please call us. Our friendly technical sales team are also HETAS registered, so you can be sure of a professional and enthusiastic service.

Chimney Block System

We stock the Isokern DM chimney block systems, which is considered to be the best available and is covered by a CE mark proving that is has passed the tough European Standard requirements.

This is a double module chimney block system consisting of flue blocks and outer casings, which are designed for quick installation and easy handling.

Made from exceptionally heat resistant insulating pumice concrete, this system can be installed inside or outside a building and can be clad in masonry or rendered to create the appearances of a traditional chimney.

Pumice concrete flue block and liners are an ideal choice for use with wood burning stoves and open fires. They have a proven tack record of over 60 years use in the tough climate of Scandinavia.

A comprehensive choice of accessories is available with the Isokern DM system, including firechests, offsets and support components that are ideal for easy installation. The DM system is available with internal flue diameters of 150, 180, 200, 225, 300 or 345mm.

We also stock the range of Isokern pumice concrete flue liners that can be used for “traditional” chimney construction.

Firechests for open fires

If you want to build a standard or extra large open fireplace the Isokern firechest is the ideal solution. They are designed to create a complete system with the DM chimney blocks, avoiding many of the variable factors that lead to draught problems and smoky fireplaces. The range includes firechests with fire openings from 500 to 1250mm.

The lightweight pumice concrete components interlock to create a robust fireplace recess and gather to support the chimney above. The joints are sealed using lip glue jointing compound. Starting from a suitable foundation and constructional hearth, it would take two people less than an hour to assemble a complete firechest and gather.

The outside of the firechest can be clad in brick, stone or rendered block work to create the desired effect. Fired bricks are used to line the inside of the recess.

The built in flue damper is a real bonus available with the Delta 500 and larger fire chests from the 950 upwards. In multi-fuel and wood burning installations the flue damper can be used to control the draft in the flue and avoid excessive heat loss when the fireplace is not being used. This is reflected in the SAP calculation for Document L. The inclusion of the damper will halve the chimney ventilation rate in the SAP calculation. It must not be installed with gas fires.


Flue liners are used to build what is commonly called a “traditional chimney” and are usually made from clay or heat resistant concrete.

A typical chimney construction would start with the liners being supported on a suitable lintel or gather if being used above an open fire. The liners are jointed using a flue jointing mortar mix, then surrounded by a minimum thickness of 100mm brick, block or stone work. A minimum gap of 25mm must be kept between the outside of the liners and surrounding masonry, and backfilled with a standard insulating concrete mix.

A choice of gathers bends and chimney pots are available.

We stock the Red Bank concrete flue liners which are a good choice for use with open fires. They are available in a range of round, square and rectangular flue sizes. The 200, 250mm and 300mm square flue liners are popular for open fires and the larger rectangular liners can be used for inglenook type chimneys. {Create link to the Inglenook chimney page}.

We also stock the Isokern pumice concrete flue liners that are ideal for chimneys being built for use with wood burning stoves.

We can help with ideas and answers for almost any situation, so please call us. Our friendly technical sales team are also HETAS registered, so you can be sure of a professional and enthusiastic service.

A few words about Building Regulations It is a legal requirement that all chimney installations comply with the Building Regulations, which for England and Wales is explained in the Approved Document J. These are minimum requirements aimed at making sure installations are safe. There are also Planning Permission requirements, which are explained on the Regulations page.