Building services · Plymouth & Devon
Plymouth Builders for Extensions, Conversions & New Builds
MAG Developments SW are full-service Plymouth building contractors. From a single-storey rear extension in Plymstock to a barn conversion in the South Hams — we handle design, planning, build and handover, with one accountable project manager from start to finish.
- Fully Insured
- Building Regs Approved
- 30+ Yrs Combined Experience
- 12-Month Workmanship Warranty
- Same-Day Reply
Our services
Every trade covered, by one local team.
House Extensions Plymouth
Single-storey, two-storey and wrap-around extensions designed to add real living space and value.
View serviceLoft Conversions Plymouth
Dormer, hip-to-gable and Velux conversions. Add bedrooms, en-suites or a home office.
View serviceGarage Conversions Plymouth
Insulated, Building-Regs garage conversions for offices, gyms, snugs and annexes.
View serviceBarn Conversions Devon
Class Q, listed and rural barn conversions across the South Hams and West Devon.
View serviceGarden Rooms Plymouth
Insulated, mains-wired garden offices, studios and gyms — used 365 days a year.
View serviceRoofing Plymouth
Full re-roofs, slate and tile repairs, flat roofs and lead work — coastal-grade detailing.
View servicePatios & Driveways Plymouth
Block paving, resin-bound, porcelain and natural stone — built to depth, properly drained.
View serviceRenovations Plymouth
Whole-house refurbishments and period restoration managed end-to-end by one team.
View serviceNew Builds Plymouth
Bespoke new build homes — self-builds, replacement dwellings and small developments.
View serviceAreas we cover
Building across Plymouth, the South Hams & Devon
Not sure which service you need?
Tell us about your project and we'll guide you through the options — no pressure, no obligation.