As part of our commitment to provide a comprehensive choice for our Customers, Three Counties Steel Buildings offer an extensive selection of large, main access doors to meet precisely every need and eventuality commensurate with cost, aesthetics and long term performance.


Please click the option you require or scroll down the page to see our extensive range of main entrance doors.


Our offering of main entrance/access doors run from as narrow as 1.2m wide and as little as only 1.7m tall up to 20m+ wide and 10m+ high. This is achieved through a range of offerings and specifications including steel roller doors, sectional overhead doors, sliding doors, concertina doors, quick acting doors, strip curtain doors and hydraulically operated single panel swing doors. Each type of door has its own range of benefits however price very often has a large bearing on the selection process as these can vary significantly. Our fully trained Sales Team will advise on solutions for specific applications and you can rest assured that we never over specify and sell something our Customers don't need.





This is the traditional solution to many main entrance steel door requirements and can be supplied in a range of duties from light use (similar to domestic garage doors) through medium and up to heavy duty suitable for factory use. Steel roller doors can be un-insulated or moderately, but not highly, insulated.


The light duty steel door is formed from, effectively, a continuous single 'skin' which flexes to allow the door to be rolled. Heavy duty doors benefit from stronger 'laths' which typically slide together and each lath forms, in effect, a hinge allowing the door to roll. Should door leaf repair be required then on the lighter duty door the whole panel will need to be replaced whereas on the heavy duty door individual laths can be changed.

The decision as to which option is more suitable for a typical door of a 3m x 3m size is one of frequency of use and levels of abuse/security that is required.


Due to their nature we recommend that above 4m wide or 4m high doors should always be of the heavy duty nature due to their weight. The heavy duty door is available up to 8m wide and 10m high if required. Naturally these very large doors benefit from being power operated.

Typically the larger steel roller doors have a chain, or pole, manual override in the event of power failure.


Because of their very nature, roller doors require space above the opening for the door to roll. This varies dependant upon the type of door and the opening height but typically between 500mm to 600mm is required above the door 'head' to accommodate the door. This can have repercussions on the height of the building if the door is to be put in a side wall below the guttering as it can demand a taller building just to accommodate the door roll. There are options such as positioning the roller door in the gable end of the building or opting for an alternative type of door. Please talk to our Sales Team if you need any guidance on this matter as they will be pleased to oblige.


Of course should a door be positioned in the side wall then the bay length of the building ordinarily needs to be wide enough to accommodate the door width plus its associated mechanism and frame. If the bay length is insufficient then Three Counties Steel Buildings are expert at providing special frames to support the portal frame at that proposed door position. Of course, due to the nature of the undertaking there would be an extra cost for such work..

The entire steel roller door range from Three Counties Steel Buildings are available in a wide range of finishes including galvanised (typically the cheaper yet one of the most durable options), powder coated or Plasticol (a tough leather grain effect plastic finish) all in a wide range of colours.




The Three Counties Steel Buildings selection of steel sectional over head doors is constructed from horizontal panels (each panel typically in the region of 400mm wide) which slide on a track up into the roof in a gentle arc. The steel door therefore is not rolled up, as a steel roller door does, but moves into the roof space above the door entrance. Due to its construction therefore headroom requirements for this type of door are less than a typical steel roller door. This can be of significant benefit.


The panel construction used in our steel sectional overhead doors lends itself to insulation and low U values can readily be achieved thereby ensuring minimum energy consumption.

Vision panels are an option if required and our sectional steel door range is available in a wide range of finishes including powder coated or Plasticol (a tough leather grain effect plastic finish) all in a wide range of colours.




This option of door consists of one or more panels on a track that typically runs outboard of the building line. The fewer the panels the lower the cost however large panels often mean that the track system needs to extend past the side of the building. This can look unsightly and can take valuable spec from the allotted plot.


The door panels in such a system can be clad as insulated or un-insulated or any selected finish. However, generally due to their bulky nature, sliding doors are often made up on site which can make them costly.


Sealing such a door system can often be problematic so whilst it can offer a solution in certain circumstances 3CB would prefer to offer this type of door very much as a last resort.




Typically we offer this type of steel door when headroom, for a roller type of steel door, is unavailable or when widths are larger than the typical 7m that is towards the upper limit of a normal roller or sectional steel overhead door.


This type of steel door is usually supported from an overhead track and guided by a track in the ground. Alternatively the weight of the door can be carried at floor level with a guide system above.


Doors can be supplied by ourselves which can open and stack within the opening or 'nest' behind the opening.


Doors can be provided insulated or un-insulated, though having an insulated concertina steel door means the 'nesting' thickness is increased significantly.


Finishes are available as galvanised, powder coated or Plasticol finished in a range of colours and available with vision panels of required.




Generally offering very little in the way of security these flexible panels doors are used as a wind and rain exclusion door that also allows rapid operation for prompt and easy access and egress for forklift trucks etc. These doors, which are exclusively power operated, can be activated by remotes controls, panel boxes or induction loops set within the floor.


Typically this door is installed close to a main steel roller or concertina door such that security can be effected by closing the main door, whilst normal traffic can flow rapidly through the fast acting roller door during the normal working day when security is not an issue.




As a low cost semi transparent system for minimising rain and wind ingress, a strip curtain door is often the best choice. Requiring no power traffic can enter or leave the building by passing through the strips of the door. Dependant upon the strengths of prevailing winds etc Three Counties Steel Buildings offers a range of strip widths and overlaps together with strip thicknesses.


Typically this door is installed close to a main steel roller or concertina door such that security can be effected by closing the main door, whilst normal traffic can flow easily through the strip door during the normal working day when security is not an issue.




Three Counties Steel Buildings offer this type of door as they can be provided with huge widths of up to 40m wide and up to 10m high giving the ideal solution for aircraft and helicopter hangars and large equipment buildings.


Integrated within one of our steel buildings this system of door, which is typically hydraulically operated, is top hung and swings out to offer the very maximum of headroom without the need to accommodate head gear.


The panel itself is extremely robust and since the lower portion of the panel is away from the gear accidental damage is much less likely to affect the door operation. This can be of major benefit to operators with large plant and equipment being brought not the building as we have seen many doors damaged under such circumstances. Likewise the very robust nature of the product means ram raiding and forced entry are minimised.


The panel lends itself to a range of in-fills to assist with security, insulation and aesthetics as well as any number of options including the inclusion of personal access doors.


Since the door panel is top hung, when up, it offers a very useable canopy which can be of benefit to extent the effective floor area. Clearly such doors require a power supply so in the event of power failure we offer the option of a back up battery operation. If you are looking for a PA Door click to visit our PA DOOR PAGE


If you have any questions regarding the door specification of your building please contact our trained sales team at Three Counties Steel Buildings Ltd on 01531 822 251 or email .

A typical uninsulated hangar door of a concertina design. In this instance the door was un-insulated and sized at 14m x 5m​

The interior and exterior views of an attractive insulated hangar door sized at 17m wide x 5.5m high​

A tall roller door in one of our uninsulated building with louvered side walls. Sized at 6.5m high x 7m wide the door has to be motorised as the reduction gearing required for a manual lift would take a long time.​

Our show building with two 4.90m wide electrically operated domestic grade roller doors.​

Intyernal and external photographs of an insulated sectional overhead door. Noting the tracks run in and over the head of the door since the panel depths of the door are large and thus won’t ‘roll’. Such a door is well insulated, smooth and relatively quiet in operation.​

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