10-year structural warranty
Insurance-backedAll extensions, loft conversions and new builds are covered by a 10-year insurance-backed structural warranty via our TrustMark / FMB scheme. Cover transfers to new owners if you sell.
Guarantees & warranties
Built to last. Backed in writing.
Every MAG Developments SW project comes with the kind of cover you'd want for your own home — insurance-backed structural warranty, workmanship guarantee and full public liability.
24-month workmanship guarantee
Direct coverAny defect in our workmanship reported within 24 months of handover is rectified free of charge — no excess, no quibble. We'll be back on site within 14 days of your call.
£5m public liability insurance
Aviva-backedEvery project is covered by £5m public liability and £10m employer's liability insurance. Certificates available before any work starts — just ask.
Building Control sign-off
Council certifiedWe manage Plymouth City Council Building Control inspections and supply the final completion certificate at handover. Required for re-mortgage and resale.
Fixed-price contract
Written contractYour quote is the price you pay. Any genuine variations are documented, costed and signed off in writing before work proceeds — no end-of-job invoice surprises.
Manufacturer-backed guarantees
10-25 yearsRoof tiles, windows, doors, boilers and structural steels all carry their own manufacturer warranties — typically 10-25 years. We register every one in your name.
FAQs
Cover questions, answered.
Want to see our certificates? Request copies here — we'll send them by email within the working day.
What's actually covered by the workmanship guarantee?+
Anything that fails because of how we built it — cracking plaster, leaking joints, poor finish, doors that don't close. We don't cover wear and tear, accidental damage or work altered by a third party.
How does the structural warranty work if I sell?+
It's an insurance-backed warranty registered to the property, not to you personally. New owners benefit from the remaining cover at no extra cost — a real selling point.
What if MAG Developments SW ceased trading?+
The structural warranty is insurance-backed by an FCA-regulated underwriter, so cover continues independently of us. Workmanship items are also covered under our FMB membership.
Is my deposit protected?+
Yes. Deposits are held to the FMB code of practice and kept in a separate client account until milestones are signed off. We never take more than 10% upfront.
How quickly do you respond to a warranty call?+
We aim to assess within 48 hours and, where it's a defect we're responsible for, return to fix within 14 days. Emergencies (e.g. water ingress) are same-day.
Build with confidence.
See our accreditations or start your project today.