Slats, materials and performance · Rolling Shutter Guide
What is end retention on a rolling shutter, and when do you need it?
End retention puts a screw at the slat joints whose head runs in its own channel inside a special guide rail, so high wind, storm debris or a break-in attempt cannot easily push the curtain out of its tracks. It suits wide, exposed or high-security openings; Roll-A-Shield fits it on every 63 mm single-wall extruded shutter.
Key facts
- Two levels: every other slat (long and short screws alternate) for high security, or every slat (a long screw on every slat) for maximum security and the widest spans. Roll-A-Shield data
- A Roll-A-Shield 63 mm single-wall curtain always runs in an end-retention rail, with retention in at least every other slat. Roll-A-Shield data
- The end-retention rail takes up 2.944 in on each side of the opening. Roll-A-Shield data
- Retention in every slat needs a slightly bigger box for the same curtain height: an 8 in box holds up to 97 in of curtain with every-slat retention against 105 in with every-other-slat retention. Roll-A-Shield data
Applies to: Rolling shutters with extruded slats and end-retention guide rails; Roll-A-Shield's 63 mm single-wall shutters, solid and perforated. Roll-A-Shield's 38 mm insulated slat cannot take end retention.
On an ordinary rolling shutter, the curtain is held only by its slat ends sitting in the guide rails. Push hard enough against the middle of the curtain, with wind, debris or a tool, and a slat can pop out of the rail and free the curtain. End retention locks the slat ends into the rails to prevent that.
How does end retention work?
A retention screw is fitted at the slat joints, and its head runs in a dedicated channel inside an end-retention guide rail. The teeth of that channel block the screw heads, so the curtain cannot be pushed out of the rail.
An end-retention rail has three channels instead of the usual two: a channel the slats run in (lined with felt weather strip), a channel for the retention screws, and a channel for fixing the rail to the building, which is hidden by a snap-in cover. On Roll-A-Shield's single-wall shutters, each retention bolt carries a grommet; a bolt that is taken out and refitted is snugged up but left loose enough for the grommet to roll.
Combined with the strength of solid extruded aluminum, end retention is a major source of a single-wall shutter's extra storm and security strength.
Every slat or every other slat?
End retention comes in two levels, and the choice is made when the shutter is ordered.
| Every other slat | Every slat | |
|---|---|---|
| How it is built | Long and short screws alternate | A long screw on every slat |
| Use for | High security; most jobs | Maximum security |
| Running | Less friction, quieter, lower cost | More friction, higher cost |
| Box size for the same curtain | Smaller | Slightly larger |
Roll-A-Shield generally recommends every other slat: it gives the right security for most openings with a smoother, quieter, more affordable shutter. Every slat is for the widest spans and maximum-security jobs.
Which shutters can have end retention?
On Roll-A-Shield shutters, end retention goes with the extruded slat.
| Slat | End retention |
|---|---|
| 38 mm insulated | Not available |
| 55 mm insulated | Not a standard option; ask before ordering |
| 63 mm single-wall, solid | Always; every other slat or every slat |
| 63 mm single-wall, perforated | Always; same rail as the solid slat |
Because single-wall curtains always run in the end-retention rail, switching an opening from an insulated slat to single-wall means new guide rails as well as a new curtain.
When do I need end retention?
There is no width rule for it. End retention comes with choosing a single-wall shutter, and the level, every slat or every other slat, is chosen for the opening. Consider it when:
- The shutter has open air behind it, such as a patio, carport or porch enclosure, or stands in a high-wind spot. Wind can push an insulated curtain out of its rails there; the choice is a single-wall shutter with end retention, or an insulated shutter with a storm bar.
- Security matters most, as on many storefronts and other high-value openings.
- The opening is very wide; the widest spans need retention in every slat.
A shutter mounted directly against a wall, window or door, with no open air behind it, usually does not need it.
Does end retention change the size of the shutter?
Slightly. The end-retention rail takes up 2.944 in on each side of the opening, against 3.346 in for a standard rail. Retention in every slat also needs a slightly larger box for the same curtain height:
| Box size | Curtain height, every slat | Curtain height, every other slat |
|---|---|---|
| 6.5 in | Up to 48.5 in | Up to 57.5 in |
| 7 in | Up to 77 in | Up to 82 in |
| 8 in | Up to 97 in | Up to 105 in |
| 9 in | Up to 122 in | Up to 132.5 in |
| 10 in | Up to 150 in | Up to 162 in |
| 12 in | Up to 215 in | Up to 252 in |
The chart runs past the tallest shutter Roll-A-Shield builds, which is 216 in.
Stop: If a curtain has come out of its rail, do not keep running the shutter. Have it inspected; see Shutter came out of the guide rail or, in metro Phoenix, book a repair.
To order single-wall shutters or ask which level of retention an opening needs, call (480) 921-0200.
Watch it done
Product Overview – Guide Rails
The written steps on this page are the reference; the video shows the same job.
Frequently asked questions
Can I add end retention to my existing foam-filled shutter?
Not as an add-on. On Roll-A-Shield shutters, end retention comes with the 63 mm single-wall extruded slat and its end-retention guide rails, so it means a new curtain and new rails. On a foam-filled shutter in an exposed spot, a storm bar is the usual alternative.
Does a shutter with end retention still need a storm bar?
A single-wall shutter with end retention is normally not fitted with a storm bar, because the retention keeps the curtain in its rails. On very large, exposed commercial openings the two can be specified together; ask when you order.
Parts and next step
Need a part or a hand?
Ordering single-wall shutters and not sure whether to choose every slat or every other slat? Send the opening sizes and location and we will advise. Call (480) 921-0200; the factory answers technical questions for any rolling shutter, not only ours.