Ealing Council does not publish its Article 4 directions on planning.data.gov.uk, so for extra restrictions in your conservation area you have to ask the council itself. Until an answer comes, the general rules for England's conservation areas give you a benchmark.
Garden suburbs and the other conservation areas
In Brentham Garden Estate, 92% of the 434 houses have solid walls without insulation; in Bedford Park it is 82% of 431, and there are also 132 listed buildings there. External wall insulation on such a wall requires planning permission; internal wall insulation can be done without it. In Cuckoo Estate, solid walls account for 4% of 1,252 houses, and 79% are on gas. Across Ealing as a whole the figure is 49.4%, close to the 48.7% for England's conservation areas.
Heat pumps in conservation areas
According to the EPC register for November 2026 there are 89 of them, 25 of which sit in the largest conservation area, Ealing Town Centre (1,883 houses). If your street lies on the edge of a conservation area, check it against that area's page or with the council. The rules here are the national ones as at 21 October 2026; the planning decision rests with Ealing Council.