MFM Building Products Flex Clad 400, Flex Clad 250 Installation Manual

INSTALLATION INSTRUCTIONS

AND

READ COMPLETE INSTRUCTIONS BEFORE INSTALLATION!

• Ducts must be sealed and airtight; insulation secured properly with seams taped and corners reinforced.

• Substrate must be clean & dry. Installation works best at temperatures above 40° F (4° C).

• To improve adhesion in cold weather and on the duct bottoms, use MFM Spray Adhesive.

• For FlexClad-400, duct bottoms over 24” (60 cm) wide require use of pins.

• Top of duct must be sloped for drainage to prevent standing water.

• Use over metal duct or on rigid insulation only!

• Pressure sensitive adhesive: always roll firmly with a hand roller, especially on seams and duct bottoms.

STEP 1: Prepare the Surface

• Clean, primed metal ductwork, and rigid foil-faced insulation (polyiso-board

or FSK) are preferred substrates. FlexClad may also be installed over rigid,
foil-faced EPS and extruded polystyrene (XPS) insulation. Do not use over

non-rigid insulation!

• Surface must be free of dust, dirt, oil, dew, moisture, frost and other foreign

material that will prevent proper adhesion. Wipe surface with acetone to
remove oils, grease, hand prints, and processing lubricants.

• Insulation without a foil-facing, such as extruded polystyrene, requires the

use of MFM Spray Adhesive.

• Prime bare metal surfaces with MFM Prime-A-Seal or asphalt primer.

• HINT: Use metal reinforcing strips on insulation corners to maintain shape

for a neat appearance.

• HINT: Tape gaps between insulation boards.

STEP 2: Measure & Cut

• Measure the length of FlexClad needed and cut with utility knife or scissors.

STEP 3: Use MFM Spray Adhesive (optional)

• MFM Spray Adhesive improves adhesion in cold weather, on shaded

surfaces, and in hard-to-reach areas.

• Apply a light coat of MFM Spray adhesive and let dry for a minimum

of 30 seconds or until no longer wet.

STEP 4: Apply FlexClad

• Position pre-cut piece of FlexClad into place.

• Remove release paper from one end of FlexClad and stick membrane into

position and align.

• Pull release paper from behind the membrane and continue to press FlexClad

into place.

• Roll entire surface firmly with a hand roller.

Remove release paper, align membrane

and press to stick.

Pull release film from behind membrane

and continue to press into place.

STEP 5: Applying More FlexClad

• Overlap FlexClad 3” (8 cm) on side laps and 6” (16 cm) on end laps.

• HINT: Use a tape measure to mark overlaps. Measure and press end of tape into

membrane to leave an overlap mark. (see photo at right)

• Firmly roll all seams and edges with a hand roller to ensure good adhesion!

Position FlexClad into place.

Roll entire surface firmly with a hand

roller to ensure good adhesion.

• COLD WEATHER HINTS: Keep rolls of FlexClad in a warm place until ready to

apply. Use MFM Spray Adhesive before applying FlexClad.