One isolating valve on both loft tanks inputs?
There may be (or have been in the past) rules or conventions about the F&amp;E tank especially on solid fuel systems, to ensure they can't accidentally run dry. 

However in the past some F&amp;E tanks for gas central heating were installed without any cold supply at all, were initially topped up with a jug, and then left to get on with it. It was assumed there would be negligible evaporation loss, and the advantage of a very limited quantity of water to escape in the event of a leak. This was often on housing scheme work where hundreds of houses were done in one job and the saving of hundreds of ballvalves would mount up. 

I believe current regulations require a service valve for every outlet. 

It may also be useful to fit a drain tap at the base of that riser to the loft, so that pipe can be drained down if necessary.