Parts, boxes, rails and mounting · Rolling Shutter Guide
How big is a rolling shutter box? Box, end cap and hood sizes
Roll-A-Shield shutter boxes (also called hoods or housings) come in six sizes, 6.5 to 12 in (165 to 300 mm). Each is roughly square in section, so it sticks out from the wall roughly as far as it is tall, and a cast-aluminum end cap closes each end. The curtain height and slat type decide the size.
Key facts
- Nominal box sizes are 6.5, 7, 8, 9, 10 and 12 in, or 165, 180, 205, 230, 254 and 300 mm; the actual heights run from 6.575 to 12.008 in. Roll-A-Shield data
- The boxes and end caps are roughly square in section, so a box projects from the wall roughly as far as it is tall; treat that as approximate and confirm the depth when space is tight. Roll-A-Shield data
- The box is chosen by curtain height, which is the clear opening height plus 2 in: a 38 mm shutter over a 58 in opening fits the 6.5 in box, and over a 59 in opening needs the 7 in box. Roll-A-Shield data
- End caps come as a left and right pair, in short-leg and large-leg versions; 55 mm insulated shutters in 8 and 9 in boxes use large-leg caps and flared rails. Roll-A-Shield data
- A box and its end caps must come from the same box line; caps from one line are slightly thicker than another's, so they do not suit its box. Roll-A-Shield data
Applies to: Rolling shutters with a head box (hood) and end caps, any make; Roll-A-Shield 6.5 to 12 in boxes on 38 mm and 55 mm insulated and 63 mm single-wall shutters.
The box is the enclosure across the top of a rolling shutter. It holds the axle, the operator and the curtain when it is rolled up. People call it the box, housing, hood, headbox or cassette. This page gives Roll-A-Shield's box sizes in both units, how far each one sticks out, and what the end caps and cover are.
What sizes do rolling shutter boxes come in?
Roll-A-Shield builds six box sizes, named by their nominal height.
| Nominal box | Metric | Actual height |
|---|---|---|
| 6.5 in | 165 mm | 6.575 in |
| 7 in | 180 mm | 7.204 in |
| 8 in | 205 mm | 8.15 in |
| 9 in | 230 mm | 9.055 in |
| 10 in | 254 mm | 10.039 in |
| 12 in | 300 mm | 12.008 in |
How far does a shutter box stick out from the wall?
Roughly as far as it is tall. The boxes are roughly square in section with the front-bottom corner bevelled, and the end caps are about as wide as they are tall: a 165 mm cap measures about 164 × 164 mm. Treat that as an approximation, not a dimension: one Roll-A-Shield job note gives a box about 7-1/4 in tall and 6-1/2 in deep. Where depth is tight, ask for the figure for your box size before you build around it. The guide rails stick out much less than the box.
Which box size will my shutter need?
The smallest box that holds the rolled-up curtain, so it depends on the curtain height and the slat. Read the chart against the curtain height, which is the clear opening height plus 2 in. For example, a 38 mm shutter over a 58 in tall opening has a 60 in curtain and fits the 6.5 in box; over a 59 in opening it needs the 7 in box.
| Slat | Boxes used |
|---|---|
| 38 mm insulated | 6.5 to 9 in, and 10 in for curtains taller than 134 in |
| 55 mm insulated | 8 to 10 in, and 12 in for curtains taller than the chart |
| 63 mm single-wall | All six, 6.5 to 12 in |
A very wide shutter can step up one size so the axle does not sag. The full height-by-box chart is on Do taller shutters need bigger boxes?, and What size box do I need? covers headroom.
What is the box made of?
An aluminum enclosure made as two halves, a front-bottom piece and a top-back piece, closed by an end cap at each end. The front is a removable cover held by four screws; take it off to reach the axle, the motor or the entry guides. Some boxes have a small 1/4 in lip along the bottom edge, which slides behind the guide rails when the box is seated. Inside each end, a metal safety plate keeps the slats from catching as they move.
What do the end caps do?
The end caps close the box, carry the axle and the operator, and locate the box on the rails.
- They come in pairs. Each shutter has one left and one right cap, shaped to the box profile.
- The ears drop into the rails. The bottom of each cap (the ear) slides down into the top of a guide rail. Caps and ears are cast aluminum and can break if forced in or put under undue stress or weight.
- They hold the axle. One cap carries the motor or drive; the other carries the axle bearing.
- They come in short-leg and large-leg versions. A 55 mm insulated shutter in an 8 or 9 in box uses large-leg caps, and its rails are flared 1 in to clear the larger ear. See flared rails and entry rollers.
- They may be drilled. A motor cord or a manual-override wand can leave the box through a hole drilled in the end cap.
Each cap is fixed to the box with rivets or self-drilling screws at the corners. A box and its caps must come from the same box line; caps from one line are slightly thicker than another's, which changes how long the box is cut.
How is the box fixed to the wall?
With one screw in each corner of the box near the safety plates, and a third in the middle on shutters over 8 ft wide. Do not overtighten them: a box pulled hard against the wall distorts and rubs on the curtain. The box must be fastened to a strong, stable structure.
Safety: A box with the curtain inside is heavy. Have a helper lift and hold it in place, and keep weight off the cast ears.
What next
For a box hidden in a soffit or wall pocket, see Planning a hidden shutter box. To replace a box, cover or end cap, call Roll-A-Shield at (480) 921-0200 with the box size, color and a photo of the end cap; for a new shutter, request a quote.
Frequently asked questions
Is a shutter box the same as a hood or cassette?
Yes. Box, housing, hood, headbox and cassette all mean the aluminum enclosure above the opening that holds the axle, the operator and the rolled-up curtain.
How much room do I need above the window for the box?
On a surface mount, the box's height plus about 2 in, because the bottom slat stays below the box when the shutter is fully open. For a 6.5 in box that is about 8-5/8 in of wall.
Can I get a smaller box than the chart gives?
Not for the same curtain. The box must hold the whole rolled-up curtain, and a very wide shutter can even step up one size to limit axle sag. A shorter curtain or a thinner slat is what gets a smaller box.
Can I buy a replacement end cap?
Yes. End caps are sold by size, side and leg, and must match the box line. Call (480) 921-0200 with the box size, color and a photo of the end cap.
Parts and next step
Need a part or a hand?
Replacement motors, remotes, straps, slats and hardware ship from our Tempe, Arizona factory. Phoenix-area owners can book a service visit; everywhere else, our technicians help by phone. Call (480) 921-0200; the factory answers technical questions for any rolling shutter, not only ours.