Muntin / H Section Fitting Instructions
Before you start make sure that all sections that are to be joined are cleaned of dust
and oil and that they are dry.
Ensure that your sealed units are not taped as this may undermine the seal and cause a
failure in the sealant resulting in a leak at a later date.
If need be use a “Stanley” blade and remove the tape from the unit edge on the faces to
be sealed.
Use only the correct sealant for your glazing material.
First apply a generous bead of sealant along the inner faces of the “H” between where
it is grooved and the outer lip, only do the two faces on the side you are fitting first.
Next apply a generous bead of sealant onto both outer faces (upper and lower face) of
the panel/glazing you are inserting into the “H” section.
Put the sealant onto the very edge of the outer faces so that it is the first thing the “H”
comes into contact with and don’t be stingy with your sealer.
The reason you have put sealant onto these four faces is because when you insert your
panel/glazing into the “H” some of the sealant is pushed into the open mouth of the
“H” whilst the sealant on the panel is smeared onto the panel itself so that sealant is
now completely covering the internal faces of the joint.
Now insert your glazing panel into the “H” and slowly push the two together until the
panel is fully inserted, do this slowly to allow the sealant to be drawn along all faces.
Next using something like a 1mm glazing packer carefully remove the excess sealer
from the outer surfaces…
Important … do not use any solvent as this will weaken your
seal. …
Only use a dry cloth to clean this joint
Now with your sealant still wet using a fine nozzle make a neat joint along the
intersection of the “H” and your glazing … Job done!
Please do not try and take a short cut because you may cause a leak.
If you fit the “H” dry and just seal the edge you will get a leak!

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