Garage Door Sizes And Measuring

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Garage Door Measuring

Up and Over Garage Doors When taking measurements for a new garage door or to replace an existing one it is important to realise that different garage door types use very different criteria to specify, order or price the actual door. Also remember many headline prices you see may not include the fixing sub frame or other essential items to make the door actually operate. You always need much more than just the door panel itself.

If you are looking for a new garage door then the most basic measurements to take to begin discussions are:

  • Width and Height of existing brickwork opening

  • Internal Headroom (measure clear space from under the lintel to the ceiling)

  • Internal Reveals (the width of the face showing either side when you stand in your garage looking out)

Most of you will contact us with the actual door panel size, which is fine, but only gives us half the information we need. We have to know the structural size to make sure any new door will either fit to the existing frame or take a whole new door, gear and new frame.

Then make a note of any obvious obstructions in the garage and you can then begin looking for an appropriate garage door with your measurements at hand - most handy if you are speaking to us rather than the favourite phrase 'it's just a standard one'.

You could also download our survey form and fill in the details before talking to us.

Find the form here

Up and over measuringBelow are some basic tips and facts:

Up and Over Garage Doors

Important first fact:  All up and over garage doors require a fixing sub frame for installation and this must be taken into consideration when measuring, ordering or installing. 

Up and over garage doors are always ordered by their internal fixing sub frame dimensions in the U.K.. In other words the internal width and height of the sub frame opening which is either timber or steel box section.

Measure your existing up and over garage door inbetween the sub frame (open the door) and for example you may get a measurement of 7'0" (2134mm) for the width and then 7'0" (2134mm) from the floor to the frame head. This is then a 7' x 7' garage door (7070) and the door panel measurement itself is irrelevant as different manufacturers always allow different tolerances in the panel depending on other factors.

By all means measure the existing garage door panel itself but we do need the other measurments as well.
(Surprisingly standard stock up and over garage doors are still ordered in imperial even though the imperial size may not be exactly the measurements of the internal frame)

When a garage door is fitted inbetween a brickwork opening the measurements are much more critical than when fitted behind (inside) the garage opening as operating gear and springs will vary from one manufacturer to another meaning you cannot always just replace an old up and over with a new one with new gear as it may require a wider frame than the old door has.

More information on up and over doors here


Sectional Overhead Garage Doors

Sectional measuringImportant first fact:  All sectional garage doors are ordered by the internal dimensions of the steel frame opening and all sectional doors have a steel framework for installation. 

Most sectional garage doors are installed behind (inside) the garage opening to maximise drivethrough dimensions and most have quite large space requirements for the frame legs and the height required for the curved part of the track the door panels move in. However because a sectional garage door does not go through the opening it is possible to install sizes larger and smaller than your actual opening on the width and height. Very rarely will a standard size sectional door be the exact size when replacing an old door.

A sectional door will also come into the garage a lot further on the horizontal rails so it is essential you have clear room at least the height of the door plus 350 - 600mm (on average) into the garage.
(Strangely, most sectional garage doors are ordered in either imperial or metric measurements but quite often the imperial measurement is not quite the actual size of the door, but a near reference size)

more info on sectional doors here


Roller Shutter Garage Doors

Important first fact: Roller shutter doors are ordered by different dimension depending on different manufacturers. BEWARE, some use the daylight opening size and others the overall size, some also order the width by the curtain width.

Generally for a roller door you install the tracks and the support brackets for the curtain roll inside the garage opening for maximum use and in many cases because the average roll size for a roller door is between 300 and 450mm it needs to go behind the lintel to maintain drive through height.

Modern roller shutters do not require a sub frame as the tracks fit directly to the garage structure. Insulated roller doors can fit inbetween a structural opening where as most non insulated steel roller doors must fit behind a structure as the track guides are very different.

(Most roller door manufacturers now produce doors to exact sizes and you only ever tend to see standard sizes shown in special offers and the like)

More info on side hinged doors here

Side Hinged Garage Doors

Important first fact: Side hinged garage doors need a timber or steel sub frame and with a timber sub frame need 'hanging' correctly, usually by a skilled carpenter. Steel framed side hinged doors usually come pre assembled.
It is possible now to order timber garage doors with a prefitted steel sub frame, ask for details.

Measurements for side hinged doors for ordering are like up and over doors where the frame internal opening size is the order reference, NOT the actual door leaves which have a tolerance built in depending on panel thickness, etc.

Most side hinged garage doors are installed inbetween the structural opening but can be installed in front (with appropriate weather sealing to frame head) of a garage to maximise length, width and height.

(Side hinged garage doors in timber are very versatile in out of square openings although timber framework is equally versatile enabling steel, GRP, ABS or timber side hinged doors to be installed)

More information on side hinged doors here

You can find a lot more information and technical specifications from manufacturers own brochures in our downloads section. Some of the files are very large so be prepared to wait if your broadband speed is a bit slow.

Better still is to pick up the phone and speak to us, it is always the best way to get the right information.

Some basic terminology usd when measuring for a garage door:

garage door measuring references for sizes


If you're unsure about how to measure for a new garage door, don't hesitate in giving our expert team a call on 01933 229135! Or, of course, we carry out professional surveys, which we will be happy to arrange with you over the phone.

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