Norseal DF1212 Double Flipper Perimeter Seal – 12 × 12mm × 2100mm

Norseal DF1212 Double Flipper Perimeter Seal – 12 × 12mm × 2100mm Technical Specifications

Norseal DF1212 Double Flipper Perimeter Seal is a self-adhesive corner profile incorporating rigid and flexible PVC components for acoustic and smoke sealing around door heads and jambs.

Product Specification

Available Colours and Product Codes

Product-Code Structure

The stocked product codes use the following format:

DF1212 / Length / Colour

The colour suffixes are:

• BLK — Black
• BRN — Brown
• WHT — White

Current Stocked Range

Typical Quantity for a Single Door

A single-leaf doorset normally requires separate sections for:

• One hinge-side jamb
• One closing-side jamb
• One frame head

A common requirement will therefore be approximately three 2100mm lengths:

• One length for the hinge jamb
• One length for the closing jamb
• One length cut to suit the frame head

This is general quantity guidance only.

Measure the complete door frame before ordering, particularly where the door exceeds standard internal dimensions.

Double-Leaf Doors

For a double-leaf doorset, additional components may be required for:

• The wider frame head
• Additional frame jambs
• The meeting stile
• The threshold beneath both leaves

The DF1212 should only be installed at the meeting stile where that use is supported by the complete doorset evidence.

Acoustic Performance Note

The DF1212 has acoustic-performance evidence in accordance with BS EN ISO 10140-2:2010.

No universal standalone decibel rating should be assigned to one seal.

Final sound reduction depends on:

• The construction and mass of the door leaf
• The door frame and stops
• The operating gaps
• The position of the corner profile
• The contact and continuity of both flippers
• The door-bottom and threshold seal
• The meeting-stile arrangement
• The glazing and ironmongery
• The frame-to-wall junction
• The quality of installation

Smoke Performance Note

The DF1212 technical sheet lists smoke performance in accordance with BS EN 1634-3:2004.

Effective smoke sealing requires:

• Continuous flipper contact
• Closely fitted corner joints
• A door that closes completely
• A compatible threshold seal
• Correct treatment of double-door meeting stiles
• Correctly sealed glazing and hardware preparations
• Installation matching the tested arrangement

Fire-Door Performance Note

The DF1212 is not an intumescent strip and does not independently provide fire resistance.

Where it is installed on a fire-resisting doorset:

• Confirm that the profile is permitted by the doorset evidence.
• Do not remove or conceal required intumescent products.
• Do not prevent an intumescent seal from expanding.
• Maintain the specified perimeter and threshold gaps.
• Do not obstruct fire-rated hinges, locks or latches.
• Confirm that the door continues to self-close and latch.

Surface Requirements

The self-adhesive mounting surfaces should be:

• Clean
• Dry
• Sound and stable
• Smooth enough for continuous adhesive contact
• Free from dust
• Free from grease and oil
• Free from loose paint or varnish
• Free from silicone, wax and polish

Adhesion may be reduced on damp, contaminated, rough, porous or unstable surfaces.

Handling and Storage

Store the DF1212:

• Flat or fully supported
• In a clean and dry location
• With the adhesive release liner intact
• With both flippers protected from crushing
• Away from direct heat and moisture
• Protected from paint, adhesive and construction debris
• Without sharp folds or permanent bends

Inspection and Maintenance

Inspect the installed profiles regularly.

Replace the specified seal where it is:

• Missing
• Loose or lifting from the frame
• Cut or torn
• Permanently flattened
• Painted over
• Contaminated with adhesive or debris
• Open at a corner joint
• No longer contacting the closed door
• Preventing the door from closing or latching

Do not replace the DF1212 with the smaller DF1010 or another profile without checking the doorset specification.

How to Install the Norseal DF1212 Double Flipper Perimeter Seal – 12 × 12mm × 2100mm

Norseal DF1212 Double Flipper Perimeter Seal is self-adhesive and fitted as a corner seal against the door stop and frame.

The two flexible flippers must face the moving door and make suitable contact when it closes.

Trial fit a short section before removing the adhesive backing from the full-length seals.

What You’ll Need

• Norseal DF1212 in the required colour and quantity
• The applicable acoustic, smoke or doorset specification
• A short DF1212 sample for trial positioning
• Tape measure
• Pencil or suitable marker
• Straight edge
• Square or mitre guide where required by the doorset detail
• Sharp utility knife or suitable PVC profile cutter
• Fine-tooth saw where required for the rigid PVC section
• Clean, dry lint-free cloth
• Suitable non-residue surface cleaner where required
• Plastic application tool or firm hand pressure
• Protective gloves suitable for cutting work

Before You Start

Inspect the complete doorset.

Confirm that:

• The door opens freely.
• The door closes completely.
• The latch engages correctly.
• The hinges and frame are secure.
• The door leaf is not significantly warped.
• The door stop is straight and stable.
• The perimeter gaps are reasonably consistent.
• The 12 × 12mm corner profile can be accommodated.
• The mounting surfaces are suitable for adhesive fixing.
• The profile will not obstruct hinges, locks or latches.
• A compatible threshold seal is provided where required.
• The installation is permitted by any applicable fire-door evidence.

Repair substantial alignment, gap or frame defects before fitting the profile.

Step 1: Identify the Corner Profile

Inspect the DF1212 cross-section.

Identify:

• The rigid 12 × 12mm corner section
• The self-adhesive mounting surfaces
• The two flexible sealing flippers
• The surfaces that sit against the frame and stop
• The direction in which the flippers must face

Do not remove the release liner until the orientation has been confirmed.

Step 2: Establish the Mounting Position

Hold a short section against the junction between the frame and door stop.

Position the rigid corner section so that:

• It sits firmly against the frame and stop.
• Both adhesive faces can make continuous contact.
• The two flippers project towards the door leaf.
• The profile remains clear of hinges and strike plates.
• The door can close against the flippers.

Mark the proposed installation line.

Step 3: Trial the Flipper Contact

Close the door slowly against the short trial section.

Both flippers should:

• Contact the door leaf
• Deflect smoothly
• Remain correctly orientated
• Remain free from folds and twists
• Recover when the door opens
• Not become completely flattened
• Not prevent the latch from engaging

Reposition the sample where the contact is excessive or insufficient.

Do not install all three sides until a satisfactory position has been established.

Step 4: Mark the Installation Lines

Use a straight edge to extend the selected position along:

• The hinge-side jamb
• The closing-side jamb
• The frame head

Maintain the same relative corner position around all three sides.

Check the marked lines with the door both open and closed.

Step 5: Check Ironmongery Clearance

Inspect the profile route around:

• Hinges
• Strike plates
• Locks and latches
• Door coordinators
• Concealed closers
• Flush bolts on double doors
• Other frame-mounted hardware

Do not cover, obstruct or alter hardware required for correct door operation.

Any interruption in the seal should follow the applicable acoustic, smoke or fire-door detail.

Step 6: Clean the Mounting Surfaces

Remove dirt, dust, grease and loose material from both surfaces of the corner.

The frame and stop must be:

• Clean
• Completely dry
• Stable
• Free from grease and oil
• Free from sanding dust
• Free from loose paint or varnish
• Free from silicone, wax and polish
• Free from old adhesive residue

Allow any cleaning product to evaporate fully.

Step 7: Measure the First Jamb

Measure the first vertical jamb from the intended upper joint to the required lower finishing point.

The lower end should:

• Finish neatly above the threshold
• Meet the door-bottom sealing zone
• Remain clear of an automatic drop seal
• Not leave a substantial open corner gap

Record the measurement accurately.

Step 8: Transfer the Measurement

Transfer the jamb measurement onto the DF1212.

Do not stretch the profile while measuring.

Mark the piece according to its intended position, such as:

• Hinge jamb
• Closing jamb
• Head

Maintain the correct corner and flipper orientation while marking.

Step 9: Cut the First Profile

Cut the DF1212 cleanly using a tool appropriate for the rigid and flexible PVC components.

Support the rigid corner section during cutting.

Avoid:

• Crushing either flipper
• Tearing the flexible PVC
• Creating an uneven end
• Stretching the profile
• Separating the adhesive backing

Form the corner-joint geometry required by the doorset detail.

Do not assume that a mitred or square butt joint is universally required.

Step 10: Dry Fit the First Jamb

Position the cut profile without removing the complete adhesive liner.

Check that:

• The length is correct.
• The rigid corner fits against the frame and stop.
• Both flippers face the door.
• The profile follows the marked line.
• The upper end aligns with the proposed head seal.
• The lower end finishes correctly.
• The profile remains clear of ironmongery.

Close the door carefully and reconfirm the flipper contact.

Step 11: Expose the Adhesive Progressively

Peel back a short section of the release liner.

Do not remove the complete liner at once.

Progressive removal helps:

• Maintain corner alignment
• Prevent accidental adhesion
• Avoid stretching the profile
• Allow minor correction during application
• Achieve continuous contact on both mounting faces

Step 12: Install the First Jamb Seal

Begin at the upper end.

Press the rigid corner section firmly against both the frame and stop while progressively removing the release liner.

Work down the jamb in a controlled manner.

Apply firm, even pressure along both adhesive surfaces.

Do not:

• Stretch the profile
• Twist the rigid corner
• Trap either flipper beneath the mounting section
• Bond the seal over dust or loose coatings
• Pull the profile away repeatedly after initial adhesion

Step 13: Install the Opposite Jamb

Repeat the measuring, cutting, trial-fitting and application process on the second jamb.

Maintain:

• The same corner position
• The same flipper orientation
• Consistent contact
• Closely aligned upper joints
• Clearance from hinges, locks and latches

Step 14: Measure the Frame Head

Measure the distance across the frame head between the installed jamb pieces.

Allow for the selected corner-joint arrangement.

Transfer the measurement onto a new DF1212 length without stretching the profile.

Step 15: Cut and Dry Fit the Head Seal

Cut the head profile accurately.

Dry fit it against the head stop and frame.

Check that:

• The ends meet the jamb profiles closely.
• Both flippers face the door.
• The rigid corner follows the frame and stop.
• The profile remains clear of closers and coordinators.
• The door can close normally.

Step 16: Install the Head Seal

Expose the adhesive progressively.

Press both mounting faces firmly against the frame and stop while working across the head.

Maintain a straight and consistent position.

Do not overlap the rigid corner sections unless the doorset detail specifically permits that arrangement.

Step 17: Inspect the Head-to-Jamb Joints

Check both upper corners.

The joints should:

• Meet closely
• Maintain flipper continuity
• Contain no substantial open gaps
• Remain free from bulky overlaps
• Not cause either profile to lift
• Not interfere with door movement

Re-cut an inaccurate section rather than forcing it into position.

Step 18: Apply Final Adhesive Pressure

Press along both adhesive faces of all three profiles.

Pay particular attention to:

• The profile ends
• The head-to-jamb joints
• Painted surfaces
• Areas close to ironmongery
• Any slight frame irregularities

Confirm that no part of the rigid corner is lifting.

Step 19: Close the Door Slowly

Close the door while observing both flexible flippers.

They should:

• Make continuous contact
• Deflect smoothly
• Remain correctly orientated
• Remain free from folds and twists
• Return towards their original shape when the door opens

Stop and correct any section that becomes trapped or folds backwards.

Step 20: Check Final Door Operation

Open and close the door several times.

Confirm that:

• The door opens freely.
• The door closes completely.
• The latch engages correctly.
• The self-closing device remains effective where fitted.
• Both flippers maintain continuous contact.
• The rigid profiles remain securely bonded.
• The door does not require excessive closing force.

Do not leave the doorset in service where the seal prevents correct closing or latching.

Step 21: Check the Threshold Seal

The DF1212 treats the head and jambs only.

Where acoustic or smoke sealing is required, confirm that the gap beneath the door is treated using a suitable:

• Automatic drop seal
• Surface-mounted door-bottom seal
• Threshold seal
• Other tested sealing arrangement

The lower jamb ends should meet the threshold-sealing zone without leaving substantial open gaps.

Double-Leaf Door Installation

Where the DF1212 is installed around a double-leaf doorset:

• Confirm the seal arrangement for the active and inactive leaves.
• Keep the profile clear of flush bolts and coordinators.
• Use the specified meeting-stile seals.
• Confirm the correct leaf-closing sequence.
• Ensure both leaves close and secure correctly.
• Treat the threshold beneath both leaves.

Do not use the DF1212 at the meeting stile unless the doorset evidence permits it.

Installation Tips

• Inspect the corner profile before removing the release liner.
• Trial fit a short section before installing the complete perimeter.
• Fit the rigid corner against the door stop and frame.
• Position both flexible flippers towards the door leaf.
• Clean and dry both adhesive surfaces thoroughly.
• Use a straight guide to maintain alignment.
• Remove the adhesive liner progressively.
• Do not stretch the PVC profile.
• Do not completely flatten either flipper.
• Keep head-to-jamb joints closely fitted.
• Keep the profile clear of hinges, locks and latches.
• Do not paint or varnish the flexible flippers.
• Do not obstruct required intumescent seals.
• Check that the door continues to self-close and latch.
• Use a compatible threshold seal where required.

Maintenance Advice

Inspect the DF1212 regularly as part of the doorset-maintenance programme.

Check for:

• Loose or lifting adhesive sections
• Separation from the frame or stop
• Cuts or tears in either flipper
• Permanently flattened flippers
• Paint or varnish contamination
• Missing profile sections
• Open head-to-jamb joints
• Accumulated dust and debris
• Loss of contact with the closed door
• Changes in door alignment
• Failure of the door to close or latch

Clean the profile using a soft cloth and a mild cleaning product compatible with PVC.

Avoid:

• Strong solvents
• Abrasive pads
• Sharp scraping tools
• Paint or varnish over the flippers
• Applying additional adhesive over a contaminated surface

Replace damaged sections using the same specified DF1212 profile and colour.

Important Performance Note

Correct surface preparation, corner alignment, flipper orientation and door-gap control are essential to the performance of the DF1212.

The profile does not independently create an acoustically rated, smoke-control or fire-resisting door.

Final performance depends on:

• The construction of the door leaf
• The door frame and stops
• The perimeter gaps
• The contact and continuity of both flippers
• The door-bottom and threshold seal
• The meeting-stile arrangement where applicable
• The glazing and ironmongery
• The frame-to-wall junction
• The quality of installation and maintenance

For certified or performance-rated doorsets, install the DF1212 only in accordance with the applicable test evidence, assessment, third-party certification and door-manufacturer instructions.