Shrink Wrap Doors and Access Points: Which Type Do You Need?

Once your shrink wrap enclosure is in place, you need a way in and out. On a small single-visit job that might mean cutting a flap and resealing it. On anything more involved — a scaffold enclosure used by multiple trades, an industrial containment structure, a modular building wrap, or a vessel under refit — you need a proper access solution from the start.

There are three main options: the step-through zipper door, the roll-up door, and the inspection hatch. Each suits different situations. This guide explains how they work, where each one is the right call, and what to consider before you install.

Step-Through Zipper Door (U-Shaped Zipper Door)

The step-through door is the most widely used access solution in shrink wrap. It consists of a U-shaped zipper sewn into a rectangle of polythene sheeting, which is taped directly onto the shrink wrap surface. When the zipper is unzipped and the flap rolled back, it creates a clear opening. When zipped shut, it provides a weather-tight, dust-tight seal.

The name comes from the design: the bottom of the U sits a short distance above the ground, leaving a lip or threshold that the user steps over to pass through. It is not a trip hazard on a well-managed site, but it is worth considering for high-traffic routes or situations where operatives are carrying heavy materials.

When to use a step-through zipper door

The step-through door is the right choice when:

• The enclosure will be accessed frequently by personnel but not by vehicles or large machinery
• A tight seal around the full perimeter of the door is needed — for dust containment, weather protection, or regulated environments
• The access point is a designated entry/exit rather than a general-purpose opening

It is used across scaffold enclosures, industrial containment structures, modular building wraps, and marine applications where an enclosed vessel or dry dock structure needs regular pedestrian access.

Installation overview

The shrink wrap sheeting must be fully applied and heat shrunk drum tight before the door is installed. The area where the door will sit needs to be clean and dry — dust or moisture will prevent the tape adhesive from bonding properly.

The door is positioned using small pieces of tape to hold it temporarily, then secured with wide tape, minimum 100mm, overlapping both the door edge and the surrounding shrink wrap. Half the tape width bonds to the door, half to the sheeting. Once fully taped, the flap is unzipped and rolled back, the shrink wrap beneath is cut away following the line of the zipper, and the cutout is discarded.

One important point: do not apply heat from the gun to the zipper door itself. Heat will damage the polythene and the zipper mechanism. 

Roll-Up Door (Straight Zippers)

The roll-up door works differently. Instead of a single U-shaped zipper unit, it uses a pair of straight self-adhesive zippers applied directly to the shrink wrap sheeting. The zippers are spaced apart at whatever width suits the opening, and the panel between them rolls upward from the bottom when unzipped — like a roller blind.

Because the bottom edge of the door is not fixed, the roll-up door does not create the same seal as a step-through door. There is no threshold to step over, which makes it easier to move materials through, but it also means it cannot match the containment performance of the U-shaped option.

When to use a roll-up door

The roll-up door is the right choice when:

• The opening needs to be wider or taller than a standard step-through door unit allows — because the zippers are applied separately, the width is adjustable
• Operatives are frequently moving materials, equipment, or tools through the opening and a threshold would create a practical problem
• The containment and weather-sealing requirement is lower — for example, a ventilated structure or a temporary working shelter where a perfect seal is not critical

It is also a useful option where a timber door frame has been constructed, as the zippers can be positioned to suit the frame dimensions precisely.

Installation overview

The shrink wrap is hung and welded in the normal way, but the area where the door will be installed must not be heat shrunk. The backing paper is peeled from each self-adhesive zipper and the two zippers are applied vertically to the sheeting, parallel to each other, spaced at the required door width. Getting them straight and evenly spaced at this stage saves problems later.

Once both zippers are applied and firmly pressed in, each one is unzipped from the bottom. A Stanley knife is used to cut vertically between the zipper teeth, cutting through the zipper backing and the shrink wrap sheeting beneath. Once both cuts are complete, the panel between the zippers rolls upward from the bottom to open.

Inspection Hatch

The inspection hatch is the smallest of the three access options. It uses the same U-shaped zipper mechanism as the step-through door but in a much smaller format — typically sized to allow a person's arm and head through, or to access a specific point such as a lifting eye, a valve, or a survey point on the structure beneath.

It is most commonly used in industrial and marine applications where the shrink wrap enclosure needs to remain fully intact but occasional access to a specific location is required without opening a full door.

When to use an inspection hatch

• Access to a single point on the enclosure is needed — a lifting eye, a connection point, a monitoring sensor
• The enclosure must remain sealed except at that specific location
• A full door would create unnecessary disruption to the structural integrity of the wrap at that point

In industrial containment work, inspection hatches are often used to allow monitoring of the work inside without breaking the containment seal. In marine refit projects, they provide access to deck fittings or rigging points without opening a full panel.

Installation overview

Installation follows the same process as the step-through door. The sheeting must be drum tight and clean at the hatch location. The hatch is taped into position with the zipper closed, then the shrink wrap beneath is cut away carefully to create the opening. The hatch zips shut to restore the seal.

Choosing the Right Option: A Quick Summary

The right access solution depends on three things: how often the opening will be used, what needs to pass through it, and what level of seal is required.

For high-frequency pedestrian access with a full weather or containment seal, the step-through zipper door is the standard choice. For wide openings or situations where materials need to move through freely and a perfect seal is secondary, the roll-up door gives more flexibility. For single-point access without breaking the main enclosure, the inspection hatch is the correct tool.

On larger projects it is common to use more than one type — a step-through door as the main daily access point, with one or more inspection hatches positioned elsewhere on the enclosure for monitoring or occasional access.

If you are unsure which option suits your project, contact the Rhino Shrink Wrap team for advice before ordering.

What You Will Need

All three door types require shrink wrap tape for installation. As a minimum, use 100mm tape — wider tape gives a stronger bond, particularly in exposed or wet conditions. On critical containment or weather-exposed installations, consider using tape on both the front and the back face of the door for additional security.

A sharp cutting knife is essential for trimming the shrink wrap cleanly around the door opening. A heat gun should be on hand to activate tape adhesive in cold conditions, but must not be directed at the zipper mechanism itself.

All zipper doors, roll-up doors, and inspection hatches are available from Rhino Shrink Wrap. See the accessories collection for current stock and sizes.