Uninsulated solid walls in St Albans' conservation areas stand at 37.1%, less than across England's conservation areas (48.7%). What is stricter here is something else: in 9 areas, including the largest, Harpenden, an Article 4 direction removes permitted development rights for windows, the roof, panels or heat pumps, and you need to apply for planning permission. That also covers Holywell Hill / Sopwell Lane, Verulam Road and others. 30 areas have no directions; there the general rules are enough.
Villages, the station and old quarters
12 of the 45 areas have fewer than 30 houses with an energy certificate (EPC) and no page of their own. Midland and GNR Railways (710 houses) has no solid walls at all, gas at 16%, 32 heat pumps. In Folly Lane, Garden Fields and the Old Hospital solid walls account for 78% of 722 houses, gas for 97%. Harpenden has 24 heat pumps across 2,395 houses; the total across the areas per the EPC register in November 2026 is 100.
Check your own street against the area page or with the council. The national rules are those of 21 October 2026; a disputed case is decided by St Albans Council.