Jonathan Blewitt

Jonathan Blewitt is the founder of Mayfair Studio, a London design studio specialising in home extensions, loft conversions and planning permission. He founded Mayfair Studio to make architectural services more accessible to London homeowners, after seeing good extension projects stall at the planning stage because the process felt opaque or costs spiralled beyond what was quoted.

Mayfair Studio combines architectural design with planning expertise, covering rear extensions, loft conversions, side returns and basement projects across all London boroughs. The studio has completed 80+ projects, from straightforward permitted development extensions in outer boroughs to complex listed building applications in conservation areas.

Jonathan built the free planning permission checker on the Mayfair Studio homepage, so homeowners can find out in minutes whether their project needs planning permission, instead of spending hours on council websites or paying for a consultation just to get a straight answer. He writes publicly about planning permission, permitted development and London borough policy, drawing on the studio's project data.

Products

• Free instant planning permission check
• Site Planning Report - £395, 24-hour turnaround
• Fixed-fee architectural drawings from £1,295

Writing

Jonathan writes detailed guides on London extensions, planning rules and construction costs, based on real project data - giving homeowners the same information their design team has, so they can make better decisions earlier in the process.

Get in touch

If you have a project in mind, the fastest way to get started is the free planning check.