Door Features
What Makes Our Doors Better Than Others?

Our Door Specifications

Our doors are manufactured to a 54- 70mm finish.

VariFold doors are usually 54-62mm thick allowing for a minimal of a 4:12:4 double glazed unit. These doors meet part L building regulations but are not as thermally insulative as our thicker doors.

InternaFold doors vary from 44mm to 64mm depending on the usage. 44mm thick doors are used if solid panels or single toughened safety glass is required. 54mm thick doors are used when standard double glazed units are required. 64mm thick doors are used when integrated blinds or triple glazing is specified.

CustomFold Doors are a minimum of 54mm thick but are approx 64mm thick when integrated blinds or triple glazing is specified.

Thicker doors mean thicker double glazed units which yield a better U Value for thermal efficiciency. See here for more information regarding double / triple glazed units and U Values.

The stiles and top rail are finished at approximately 100mm wide and the bottom rail is finished at approximately 160mm wide. The deeper bottom rail allows us to use a double mortice and tenon guaranteeing the joint will not spread or drop and keeps the door square with less chance of skewing over time.

Raw Materials

Starting out as rough sawn or engineered timber we plane and machine all our door sections to ensure each element is square, straight and to size. All our timber comes from FSC certified forests. FSC helps take care of forests and the people and wildlife who call them home and is recognised by WWF as the “hallmark of responsible forest management”. The FSC ensures that forests are responsibly managed and stay alive for future generations.

Joinery Method

We use only traditional, time tested joinery methods to ensure our doors stay perfect throughout their lifespan. Unlike many door manufacturers we use mortice and tenon joints with D4 waterproof glues. Many manufacturers use D3 weatherproof glue and dowel joints which can fail in severe weather conditions. 


All our door products are finished ready to take a paint system of your choice. We offer several finish stages. Bare, Preserver, Primed/Undercoated, Glossed as well as Stained/Varnished depending on the finish you require. Each stage is complete however the finish gloss coat will require a final coat after installation. This will cover any minor marks and scratched that will naturally occur during installation. If your system is stained or varnished we would recommend another coat after installation but it is not necessary for the paint manufacturers maintenance cycle as 2 coats will have been applied. However like the gloss system a final coat will cover any small marks made during installation. Sill section finishes can be seen below.

Hardware is supplied as set out in quotations and/or correspondence emails but will not always be fitted. I.e. Bi folding door hardware will have been pre morticed where applicable and hinge holes pre drilled but the hardware will not be fitted to the door. This is part of installation and will be supplied in individual boxes corresponding to the instructions. Door sets will not be hinged but will have multipoint lock mechanisms (where specified) prehoused ready for fitting on site. Mortice lock bodies will be pre morticed and require face plates cut in on site along with strike plates and multipoint receivers.

Protruding hardware such as tricklevents, handlesets and other items will be supplied where required but not fitted to avoid damage in transit.

Please contact us to confirm exact specifications.

Glazing will be supplied where required but will not be fitted to either doors or frames and require fitting on site after frame installation. This is due to weight and handing limitations and frame fixing reasons. All glazing tapes and silicones will be supplied. We are also happy for you to source your own glass if you have a preferred supplier.

Sill Choices

We offer 2 choices of sill for our bi folding door systems. The most common choice is our aluminium hybrid sill which incorporated a hardwood sill inlay and bottom stop. The aluminium outer sill section is self draining and comes in a choice of silver or bronze. The second option is a full hardwood sill and bottom stop with our unique drainage channel. Both sill choices come stained with an external stain/varnish. We do not recommend painting threshold timbers as the paint chips and scuffs extremely quickly. The varnish gives a lasting protection which does not show wear and damage as readily. If you do want a gloss or satin finish on the sill sections the applied stain can be overpainted after installation.

Door Set sills will come as either a solid hardwood sill for outward opening sets or a hardwood sill with aluminium threshold for inward opening sets. The style and colour of the aluminium threshold can be specified at time of order to abide by disabled access regulations. This must be confirmed via email or architectural drawings.

Rebates In Or Out

Many manufacturers glaze internally for a security point of view. The beads cannot be removed from the outside so are deemed more secure. We disagree. All our doors are beaded externally (Hodgson B6 system) and for good reason. Firstly it is almost impossible to remove a double glazed unit from the outside only. Our glazed units are bedded onto a butyl flexi tape which adheres to the unit and seals to form a watertight barrier. Then the perimeter of the unit is sealed with glazing silicone which seals and adheres the unit in place. Thirdly, the beads are fitted into a silicone bed which adheres to the glass and can not be removed without totally destroying the glazing bead. The bead is nailed every 200 mm. So the glazing beads are taped, siliconed and nailed, giving a neat and secure finish.

But why not glaze internally to be sure?

This is a simple question to answer.

If the perimeter seal does ever fail then water cannot ingress inwards. Water can only ever ingress up to our rebate and will find its way outwards. On internally beaded doors, once the perimeter seal has failed the only way water will go is inwards. Meaning leaks and unsightly water stains.

However. If you are still sure that internally beaded doors are your preferred choice, we are happy to bead internally.

We will also bead internally if hardwood glazing beads are not possible. I.e. when a softwood system is being stained. In these circumstances we will bead internally.


We are happy to work with architects and machine joinery to architectural specifications. If no architectural drawings are supplied then we will manufacture to our standard settings and designs. It is not our responsibity to check that the items ordered match your needs if no drawings are supplied, so we recommend the use of drawings with detailed specifications.

It is the customers responsibility to ensure that the product ordered meets relevant regulations with regards to security, disabled access and thermal values. As not all joinery is required to meet certain regulations it is up to the customer to ensure, locking, glazing and access regulations are met by corresponding with the relevant persons, I.e. architects, building control etc. Please see full terms and conditions of sale for further details.


54 - 70mm Thick Doors

Traditional Joinery Methods


FSC Certified Timber


10 Year Guarantee


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