Tiles and slates make your roof weather proof. When you install a roof window you have to remove some of these, greatly compromising the roofs protection from the elements.
A flashing kit adds weatherproofing back to area around the window where tiles had to be removed and helps to blend the window seamlessly into the tiles or slates. The flashing kit you need depends on what tiles you have and how you would like the window to sit on the roof.
Here are some examples of the types of flashings on their respective tiles.
Flashing kit for profiled tiles
Profiled tiles are common in the UK, this apron of this flashing kit is formed around the grooves of the tiles to ensure that rainfall travels straight down the roof as it would normally.
Flashing kit for slate
Flashing kits for slate work in a similar way, they are the same profile as the slates themselves meaning that the runoff of water continues as it would if there wasn't a window there. The side flashings for slates come in pieces that sit between each slate instead of one single length, this means the water always runs back onto the tile below and cannot flow through the side of the window onto the felt below.
Flashing kit for plain tiles
Plain tiles, these work in a similar way to the slates but are thicker and overlap at more regular intervals meaning the flashing has to be slightly different. Again this flashing kit is designed to allow water to run down the roof freely.
What do I need to know when buying a flashing kit with a roof window?
Provided you already have a window size in mind. All you need to know is what kind of tiles you have on your roof, this is more than enough information to get started. Another option to consider is if you how you want your window to sit on the roof, you have the option to have the window recessed so it blends into the roof shape.
List of Velux flashing kits and the roofs they are used with
EDZ
For standard installation of a roof window into flat or profiled roofing material
Minimum profile of 15mm and maximum profile of 45mm
Suitable for 20°-90° roof pitches
EDW/EBW/EKW
For standard installation of roof windows in flat or profiled roofing material up to 120mm in profile
Also for interlocking slate, thatch and profiled sheeting
Suitable for 15°-90° roof pitches
EDP/EBP/EKP
For standard installation of roof windows in plain tiles (max length 340mm)
Maximum tile thickness of 15mm
Suitable for 25°-90° roof pitches
EDJ/EKJ
For recessed installation of roof windows into flat or profiled roofing material up to 90mm in profile
EDJ 2000 version includes BDX insulation collar as standard
Suitable for 20°-90°
EDL/EBL/EKL
For standard installation of roof windows into slate up to 8mm thick
Not for interlocking slate
Suitable for 15°-90° roof pitches
EDN/EKN
For recessed installation into slate up to 8mm thick
EDN 2000 includes BDX insulation collar as standard
Not for interlocking slate
Suitable for 20°-90° roof pitches
List of Duratech flashing kits and the roofs they are used with
TFX
For standard installation on tiles
SFX
For standard installation on slate
UFX
For universal installation on all roof surfaces
KFP
For standard installation on plain tiles
KFF
For recessed installation on slate
Usually used for conservation windows
List of Fakro flashing kits and the roofs they are used with
EZ_
For profiled roof coverings up to 45mm depth
EH_
For deeply profiled roof coverings up to 90mm depth
EL_
For natural man-made slates up to 10mm thickness
EP_
For slates and concrete/slate plain tiles up to 16mm thickness
List of Roto flashing kits and the roofs they are used with
ZIE
For standard or profiled installation on profiled tiles 15-45mm height
SNH
For standard installation into plain tiles
Maximum thickness of 15mm
MUN
For installation into flat or profiled roofing material up to 120mm
For tile materials above 45mm height
SNO
For installation into slate up to 15mm thick
Coupled versions also available
SDS
For standard installation into interlocking slate.
