Which roof types suit conversion best
A trussed roof (common in newer builds, using W-shaped truss supports) is generally harder and more expensive to convert than a traditional cut roof (older properties, using purlins and rafters) because trusses can't simply be removed without replacement structural support — worth having this assessed early, since it significantly affects feasibility and cost.
Background checks and insurance
Given the structural nature of loft conversion work, checking a company's trading history, completed project examples, and confirming appropriate insurance (including for structural work) matters more here than for smaller, less structurally involved jobs.
How long does a loft conversion take?
Simple boarding and insulation can be done in a day or two. A full loft conversion, including structural work, staircase, and fitting out, commonly takes 6-10 weeks depending on conversion type and complexity — dormer and mansard conversions typically take longer than a rooflight-only conversion.
Red flags in a cheap loft conversion quote
A quote significantly below others is worth real scrutiny — check it includes Building Regulations coverage, proper structural floor joists (not just boarding over existing joists), and fire safety measures. Skipping any of these to hit a lower price is a serious, not cosmetic, shortcut.
Loft conversions in period properties
Older roof structures sometimes use different timber sizing and construction methods than modern roofs, which affects structural assessment, and listed properties or conservation areas have tighter restrictions on visible changes like dormers. A specialist experienced with period properties will assess these factors early, not after design is finalised.
Three steps to hiring the right loft specialist
First, ask to see photos and, ideally, visit a similar completed conversion. Second, confirm who handles the Building Regulations application and structural engineer input — directly or coordinated separately. Third, get a written quote covering the full scope, not just the headline conversion price.
What affects the cost
Cost depends heavily on conversion type (rooflight/Velux conversion is cheapest, dormer adds more space and cost, a full mansard is the most involved), whether a new staircase needs significant space reconfiguration below, and whether the existing roof structure needs strengthening. A simple boarding-and-insulation job is a fraction of a full conversion's cost.
If planning permission is refused
A refused planning application for a loft conversion (usually for conversions exceeding permitted development limits) can sometimes be appealed or resubmitted with design changes addressing the specific objection — worth discussing with your specialist or a planning consultant rather than assuming refusal is final.