Roller Garage Door Glossary

A B C D E F G H I K L M O P R S T U V W

Article 4 direction: A decision by a local planning authority that removes certain permitted development rights in a defined area, often a conservation area. Where one applies, changing a door on the front of a house, including a garage door, may need planning permission, so check before ordering.
Auto-close: A control setting that closes an electric door automatically after it has been open for a set time. It's optional on some control systems and should only be used with suitable safety devices, such as photocells, fitted and working.
Barrel: The tube at the top of a roller door that the curtain coils around as the door opens. On electric doors the tubular motor sits inside the barrel; on spring-assisted manual doors the barrel holds the springs that balance the curtain.
Battery backup: A unit connected to the door's control system that stores power and runs an electric roller door for a limited number of cycles during a power cut. It recharges from the mains when power returns and doesn't replace a mains supply.
Behind-the-opening fitting: The most common way to fit a roller door. The box sits inside the garage behind the lintel and the guide rails are fixed to the inside face of the wall either side, so the full opening stays clear. It needs enough headroom and side room.
Between-reveals fitting: A fitting position where the guide rails are fixed inside the opening, against the reveals, rather than behind it. It's used when there isn't enough side room inside the garage, but the guides take up some of the width, so the clear opening is narrower.
Bottom rail: The rigid section along the bottom of the curtain that meets the floor when the door is closed. It carries the bottom seal and, on electric doors, often the safety edge. Manual doors can have a lock fitted in the bottom rail.
Bottom seal: A flexible seal fixed along the underside of the bottom rail. It closes the gap between the door and the floor to reduce draughts, rain, leaves and dust getting in, and it works best on a reasonably level floor.
Brush seal: A strip of bristles fitted inside the guide rails, and sometimes at the box, that closes the small gaps around the curtain. It helps reduce draughts, rain, dust and leaves getting in and helps the curtain run quietly in the guides.
BS EN 12453: The standard covering safety in use of power-operated doors, including the safety devices a door needs and the forces a closing door may exert. Powered roller doors are force tested to this standard when they're commissioned.
BS EN 13241: The product standard that applies to garage doors, including domestic roller garage doors. It sets out the performance and safety characteristics the manufacturer must meet and declare. Compliance belongs to the manufacturer's tested product, and we can show you the paperwork for the door you choose.
Building warrant: The approval needed in Scotland before certain building work starts, broadly comparable to building regulations approval in England and Wales. Replacing a garage door on its own isn't usually the trigger, but structural changes, such as widening an opening, may need one.
Clear opening: The usable width and height of the opening once the door is fitted and fully open. A box fitted under the lintel, or guides fitted between the reveals, reduce it, so we measure the clear opening for each fitting option at the survey.
Control box: The wall-mounted unit, usually fitted inside the garage near the door, that holds the electronics for an electric roller door. It takes power from the supply, receives signals from remotes and keypads, and connects to the motor and safety devices.
Crank handle (winding handle): A removable handle used to open or close an electric roller door by hand during a power cut or fault. It connects to the manual override, usually from inside the garage. Keep it somewhere you can find it easily.
Curtain: The whole moving part of a roller door: the laths linked together edge to edge, with the bottom rail along the lower edge. The curtain runs up and down in the guide rails and coils onto the barrel inside the box.
Declaration of Conformity: A document issued by the person who puts a powered door into service, stating that the door meets the relevant safety requirements. We commission every powered door we fit and hand over the Declaration of Conformity with the rest of the paperwork.
End plates: The two metal plates at either end of the roller box that support the barrel and, on electric doors, hold the motor head. They're fixed to the wall or lintel and carry the weight of the curtain, so they need solid fixings.
External override: A way of opening an electric roller door by hand from outside, useful where the garage has no other way in. It's an optional extra on some doors, usually a lockable point that lets the door be released or wound open during a power cut.
Face-fixed: A fitting position where the box and guide rails are fixed to the front face of the wall, outside the opening. It leaves the full opening clear and suits garages with no room inside, but the box is visible from outside.
Force limiting: The way an electric door's control system limits how hard the door can push when it meets an obstruction. Closing forces are measured against BS EN 12453 when the door is commissioned, and the door stops or reverses if resistance exceeds the set level.
Fused spur: A fixed electrical connection with its own fuse, usually with a switch, used to supply an appliance such as a garage door motor. An electric roller door needs a fused spur or socket near the box, fitted by a qualified electrician.
Guide rails (channels): The two vertical channels fixed either side of the opening that the edges of the curtain run in. They keep the door aligned, usually contain brush seals, and typically need around 75 to 100 mm of side room each side.
Headroom: The height between the top of the opening, usually the underside of the lintel, and the ceiling or nearest obstruction above it. A roller door needs enough headroom to fit its box behind the lintel; roughly 205 to 300 mm or more is common.
Hold-to-run: A control mode where an electric door only moves while you keep pressing the control and stops as soon as you let go. Because the person operating it has to be watching the door, it's treated differently from automatic operation under BS EN 12453.
Insulated lath (foam-filled lath): A lath made from two skins of aluminium with polyurethane foam between them. Insulated laths reduce heat loss, draughts and noise compared with single-skin laths, although the door still isn't part of the house's insulated envelope.
Key switch: A key-operated switch, usually mounted on the wall outside the garage, that opens or closes an electric roller door. It's an alternative to a remote or keypad and can be a useful backup way to operate the door from outside.
Lath (slat): One of the horizontal strips, usually aluminium or steel, that link together to form the curtain of a roller garage door. Laths are either single-skin or insulated and come in different heights to suit the width of the door.
Lath sizes (55 mm and 77 mm): Common heights for insulated roller door laths. 55 mm laths coil into a more compact box and suit narrower doors, while larger 77 mm laths add rigidity across wider openings but need a larger box and more headroom.
Limits (limit settings): The settings that tell an electric roller door's motor where to stop at the fully open and fully closed positions. Correctly set limits stop the door cleanly without straining, and they're checked when the door is commissioned or serviced.
Lintel: The beam across the top of a garage opening that carries the wall or structure above. The roller box is usually fixed behind it, so its condition is checked at the survey, and any lintel replacement is priced on survey.
Listed building consent: Permission from the local planning authority for works that affect the character of a listed building, which can include replacing a garage door. Carrying out such works without consent can be an offence, so speak to the conservation officer before ordering.
LPS 1175: A security standard for the burglary resistance of doors and other building products. Under Issue 8, a rating combines a threat level letter from A to H with a delay time in minutes, such as A1 or B3. Ratings belong to specific manufacturer models.
Manual override: A built-in way to open or close an electric roller door by hand when there's no power or the motor has a fault. Most electric roller doors have one, usually operated with a crank or winding handle from inside the garage.
Obstacle detection: The ability of an electric door's safety devices to sense something in the door's path, such as a car, a person or an object, and stop or reverse the door. On roller doors it comes from a safety edge, photocells or both.
Part P: The part of the Building Regulations in England and Wales covering electrical safety in homes. Some domestic electrical work is notifiable under Part P, and the qualified electrician carrying out the work deals with this.
Photocells: A pair of sensors fitted either side of the opening that send an invisible beam across it. If something breaks the beam while an electric door is closing, the door stops or reverses. Test them monthly and keep the lenses clean.
RAL colour: A colour from the RAL system, a standard range of numbered colours used for coatings on doors, windows and other building products. Quoting a RAL number helps match a garage door to your windows or front door.
Receiver: The radio unit, built into or connected to the control box, that picks up signals from remote fobs and wireless keypads and tells the motor to open or close the door. Remotes must be programmed to the receiver before they work.
Remote fob: A small handheld transmitter, often carried on a key ring, used to open and close an electric roller door. Domestic fobs typically use rolling codes for security, and they're meant to be used where you can see the door.
Reveal: The side face of the wall within a garage opening, running from the front of the wall to the inside. Guides may be fixed to the reveals in a between-reveals fitting, and reveals sometimes need building out to suit a new door.
Roller box (hood): The housing at the top of the opening that contains the barrel and the coiled curtain. Its size depends on door height and lath size, roughly 205 to 300 mm or more for domestic doors, and it can sit behind, under or in front of the lintel.
Rolling code: A security feature in which the remote and receiver change the code they use each time the door is operated. It makes it much harder for someone to copy the signal and reuse it to open the door.
Safety edge: A pressure-sensitive strip fitted along the bottom rail of an electric door. If it touches an obstruction while the door is closing, it signals the control box to stop or reverse the door. Test it monthly.
Sectional door: A garage door made of large horizontal panels that runs up on tracks and sits under the garage ceiling when open. It doesn't swing out over the drive, but unlike a roller door it needs clear ceiling space for its tracks.
Secured by Design: The official UK police security initiative. Its product approval is given to specific products that meet its requirements, so for garage doors it belongs to particular manufacturer models. Where a model holds approval, we'll show you the evidence for that exact model.
Side room: The space needed either side of the opening to fix the guide rails. For a behind-the-opening fitting this is typically around 75 to 100 mm each side inside the garage, and it's measured at the survey.
Single-skin lath: A lath roll-formed from a single layer of aluminium. Single-skin laths are lighter and cheaper than insulated laths but offer little insulation, so they suit garages used mainly for parking or storage.
Smart receiver: A receiver that connects an electric roller door to Wi-Fi, so you can open, close or check it from a phone app. It needs a reliable Wi-Fi signal in the garage and works alongside the door's existing remotes.
Spring-assisted (manual) roller door: A roller door opened by hand, with springs inside the barrel that balance the weight of the curtain so it lifts easily. It needs no power supply and suits narrower, lighter doors, and it can be secured with a bottom-rail lock.
STS 202: A security standard used to test and certificate the burglary resistance of building products, including doors. Like other security ratings, it belongs to specific manufacturer models, and where a model holds it we'll show you the certificate for that exact model.
Supply of Machinery (Safety) Regulations: The 2008 regulations, as amended, that apply to powered doors in the UK. The person who puts a powered door into service is responsible for the risk assessment, force testing, Declaration of Conformity and UKCA or CE marking.
Tubular motor: The motor used in most domestic electric roller doors. It's a long cylindrical motor that fits inside the barrel and turns it to raise and lower the curtain, controlled by the control box on the wall.
UKCA and CE marking: Conformity marks applied when a powered door is put into service, showing it meets the relevant safety requirements. In Great Britain a powered door carries UKCA or CE marking, while in Northern Ireland CE marking applies.
Up-and-over door: A one-piece garage door that tilts outwards and up into the garage roof space on a frame with springs or counterweights. Its swinging movement needs clear space on the drive, and it can be replaced with a roller door.
VAT (standard rate on garage doors): Value Added Tax. Garage doors are standard-rated, so VAT is charged at 20%, and there's no reduced rate for garage doors. Home prices are shown inc VAT, and prices for business customers are quoted plus VAT.
Vent lath: A lath with small openings that let air pass through the door when it's closed. Vent laths help ventilation in garages used as workshops or for storage, though they also let in cold air and some dust.
Vision lath: A lath with small clear panels that let daylight into the garage when the door is closed. You choose which rows of the curtain they go in, and they're available as an extra when ordering a new door.
Wireless keypad: A battery-powered keypad fixed outside the garage that opens an electric roller door when the correct code is entered. It sends a radio signal to the receiver, so no cable needs to run through the wall.
Woodgrain foil: A printed film applied to the laths to give a timber-effect finish. It gives a roller door a wood-like look, although the horizontal lath profile means it won't look exactly like a boarded timber door.

Roller garage door glossary