About us
A trusted Plymouth building company.
MAG Developments SW Ltd is a Plymouth-based building contractor delivering extensions, conversions, renovations and new builds across the South West. We pair traditional craftsmanship with modern project management to give homeowners a build experience they actually enjoy.
Built on 30 years of combined experience.
Our directly-employed core team has been building, extending and renovating homes throughout Plymouth and the South Hams for decades. We've grown by reputation — most of our work comes from previous clients and their recommendations.
From a single-storey kitchen extension in Plympton to a bespoke new build in Saltash, we approach every project the same way: clear scope, fixed price, careful execution.
We're fully insured, work hand-in-hand with trusted local architects and structural engineers, and manage Building Control sign-off so you don't have to.
Craftsmanship
Every detail finished to a standard we'd accept in our own homes.
Honesty
Transparent pricing, clear timelines, no surprises.
Reliability
We turn up, we communicate, and we deliver.
Local
Proudly Plymouth — building for Plymouth families and businesses.
Dig deeper
More about how we work.
Meet the team
Profiles, experience and qualifications of every MAG team member.
View team →Our process
An 8-step build journey from first call to 12-month aftercare.
See process →Guarantees
10-year structural cover, 24-month workmanship, full insurance.
See cover →Accreditations
FMB, TrustMark, CHAS, NICEIC and Gas Safe approved.
View badges →Let's talk about your project.
Free consultation, honest advice, fixed-price quote.