Installing ThermaDura products is simple. A 4/12mm groove is machined into the outside of the frame to accommodate a side flashing.
The head flashing is similar to flashings used in conventional joinery. We have two differing sill details which we choose depending on your cladding. We also provide 2D and 3D flashing details for customers, architects and builders.
The sashes can be removed during installation to reduce the weight. The flashing details are available on request. Please contact us if you cannot find a design you are looking for.

There are two options for the concealed fixing of ThermaDura joinery.
Our joinery is fixed with a fastener then a reveal or Gib Board is attached to conceal the fasteners. We can also fix the joinery with screws but we prefer not to as this requires pre-drilling of the frames.


We recommend the concealed fixing method. The fasteners can be
supplied with the joinery from ThermaDura. Please inquire.

Tack first fastener 100mm from corner

Fix with 1 screw 5x40mm to joinery

Fix next fasteners at 400mm centers

Same distances for the top frame rail

Fix with (2x) 4.5x40mm screws into wall framing