Yes, and with rather less resistance than a town with a castle above it and a protected old quarter beside the water might suggest. The heritage constraint here is real, small, and drawn tightly around a handful of streets. Two conservation areas. A short register of listed buildings. A couple of ancient monuments that matter only if you are buying next to one. Most people extending a house in Saltash are dealing with an ordinary post-war home on an ordinary plot, and the only thing standing in their way is the ordinary planning system everyone else in England deals with.
Historic England lists 59 buildings in the area, of which 4 are grade one, 3 are grade two star and 52 are grade two. Listing attaches to the whole building rather than the pretty parts, which means internal alterations, window replacements, rooflights and anything structural need listed building consent as well as any planning permission, and doing the work first and asking afterwards is a criminal matter rather than a paperwork problem. That said, 59 buildings across a town of this size is not a blanket, it is a list, and the overwhelming majority of homes here are not on it.
There are two conservation areas covering the town, at Lower Fore Street and at Forder and Antony Passage. Inside those boundaries the council gains extra control over things that would be nobody's business elsewhere: demolition, work to trees, and the details of what a change looks like from the street. Permitted development rights can also be tightened inside a conservation area, so the extension your friend built without permission three streets away is not evidence of anything about your house.
Two scheduled monuments sit within the area as well. That is the strictest protection tier in the system, and it matters almost entirely for land immediately around them rather than for a semi-detached house half a mile away.
The live evidence is that people alter their homes here constantly. The planning register records 498 applications across the area between April 2024 and June 2026, including 208 in the last twelve months. That is a town where somebody is applying for something most weeks of the year, which is a better guide to what is realistic than any amount of speculation about how strict the council might be.
Practically, the split runs along the age and location of the stock rather than any town-wide policy. Only about 16% of dwellings on the council tax valuation list predate 1930, so the typical Saltash house is a post-war build with room at the side or back, where rear extensions and loft conversions frequently fall under permitted development rights and need only a lawful development certificate to prove it. Buy inside a conservation area or on the listed register and the calculation changes completely, and the sensible order is to check the constraints on the specific address before you commit rather than after your architect has drawn something lovely.
Freedom to alter a home here sits in the middle: not the free-for-all of a purely modern estate, not the straitjacket of a historic town centre where every window is somebody else's decision. Check which side of a conservation area line your address falls on before you exchange, because that single fact changes the answer more than anything else in this town.