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Undersill flashings
Extends your sill
past the insulation system below.
Undersills fit beneath existing window sills to extend them past an EWI insulated system — keeping water clear of the build-up and maintaining a clean drip edge.
If interested in our Undersill flashings, please see Undersill Sheet and then click 'Get a Quote'
Where they're used
Where an existing sill doesn't project far enough past an insulated system.
When external wall insulation is added to a building, the existing window sills are often left sitting flush with — or even behind — the new facade face. An undersill extends the sill projection to clear the system and direct water away from the wall below.
Accessories
Available with
Welded end caps
Full depth, permanently fixed
Push-in end caps
(full depth)
Full depth push-in fit
Push-in end caps
(50mm)
Shallow push-in option
Joint clips
For joining lengths neatly
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