I am about to have solar panels fitted for hot water and have found a good installer who will install them. However, what is the position involving planning permission? What would be the delay on that?

The position on planning permission for such relatively new technologies as solar panels has been confused and frustrating with local authorities giving out conflicting information on whether planning permission is needed or not.

The under the new regulations, for the installation of solar panels up to 12 sq m aperture area, or 50 per cent of total roof area, whichever is less, will be exempted development subject to the following conditions:

A 15cm maximum distance between the plane of a pitched roof and the solar panel.

A 50cm maximum distance between the plane of a flat roof and the solar panels, and that panels should be at least 50cm from the edge of the roof.

The move to clarify the planning situation is hugely welcomed given the interest in these new sustainable technologies.

You don't say what size your proposed panels are - you may have to reconsider the size based on these new regulations. So you need to go back to the supplier and work out the effectiveness in terms of water heating of the size of the panels that you will be able to install.