Using 6mm thick flat aluminum bar, we made four brackets which were attached to the chimneys either side of the house and between these, two lengths of 25mm x 4.2m square aluminum bar were fitted to act as supports for the solar panels.
The photo below shows the brackets fitted to the western end of the house.
The photo below shows the brackets fitted to the eastern end of the house.
The photo below shows the pair of mounting bars fitted between the sides of the roof.
The bars are held approx 15mm off the slates to allow the solar panel brackets to slot into place and allow rain water to flow under the panels.