Do I need Letchworth Garden City Heritage Foundation consent for solar panels?

In most of the town, yes, and it is a separate decision from planning. The Foundation's Solar Panel Design Principles, revised May 2026, say Letchworth Garden City has a Scheme of Management under which most dwellings require its prior written consent for external alterations, and the Foundation lists solar and PV panels among the alterations covered. Permitted development makes no difference: its own FAQ says any external alteration to your property will also require its Consent. You apply through its online portal, it aims to decide within four to six weeks, and an approval then lasts three years. Advice beforehand is free, and only work carried out without consent attracts a fee.