There is no meaningful average cost for listed building renovation, because two outwardly similar houses can need completely different work. What can be explained is what drives the figure.
Condition, not floor area
In new build, cost tracks area fairly predictably. In heritage work it tracks condition: structural movement, decayed timber, failed roofs & previous inappropriate repairs are the items that move a budget.
Underpinning, masonry stabilisation & roof structure work are substantial pieces of construction in their own right, & they happen before anything visible is achieved.
Materials & craft time
Matched stone, lime mortars & hand-made joinery cost more than their modern equivalents & take longer to source & install. Bespoke windows are individually measured & made rather than ordered from a range.
That craft time is usually the difference between work that reads as authentic & work that does not.
Access, protection & sequencing
Scaffolding to awkward elevations, protecting surviving features during the works & phasing so the building stays weathertight all carry real cost that is easy to overlook at concept stage.
The unknowns
Every heritage project has them. The sensible response is investigation before pricing - opening up, surveys & engineer's input - so that fewer items have to be priced as assumptions.
A contingency is not pessimism; on a historic building it is part of the plan.
Getting a price you can rely on
We place a strong emphasis on clear & transparent costing: you should understand exactly what scope is being priced, what is included & excluded, & how changes during the build would affect cost.
The commercial approach itself varies by project & is agreed with the client. You can read more about our process in how we work.
Benjamin Henry Ltd provides heritage & listed building services across Somerset & the South West, from traditional masonry & structural repair to bespoke joinery made in our own workshop.