Extending in Leamington divides on one question: is the building listed, in a conservation area, or neither. The three answers lead to three completely different projects and there is no point pricing until you know which you have.
On the later housing out through Lillington, Sydenham and Whitnash this is straightforward work. A single storey rear extension of up to four metres on a detached house or three on a semi can fall within permitted development, there is usually side access, and a skip stands on the drive. These are the most predictable extensions we price anywhere in the district.
In the four Leamington conservation areas the permitted development limits reduce and a side extension loses its rights altogether. On a Regency terrace there is rarely anywhere to put a side extension anyway, so the conversation is usually about the rear, about a lower ground floor, or about making better use of what is already there.
If the building is listed, an extension needs listed building consent as well as planning permission, and consent covers the inside as much as the outside. That is not a reason not to proceed. It is a reason to design with the constraint from the first sketch rather than trying to bolt approval onto a drawing that was never going to get it.
There is one route worth knowing on the unlisted stock. A deeper single storey rear extension, up to eight metres on a detached house or six on any other, can sometimes go through the larger home extension procedure. It is prior approval rather than full permission: neighbours are notified, they can object, and an answer comes back in about six weeks.
Our extensions work is described in more detail there, including how the inspections fit around the build.