If you’re planning to make changes to your home’s layout or structure, our St Albans structural alteration specialists are here to help. From converting two single garage doors into a double garage door conversion to installing RSJ steel lintels for new windows, doors, or open-plan layouts, we carry out all work safely, efficiently, and in full compliance with building regulations.
Our experienced team handles every aspect of the project — from the initial survey and structural calculations to steel installation, brickwork, and finishing touches — ensuring your home remains strong, secure, and visually stunning.
Many homeowners in St Albans find that their double garages with two single doors can feel narrow and awkward to use. If you’re tired of squeezing your car through, we can remove the central pier and install a robust RSJ lintel to create a single, wider double-width opening.
This upgrade not only improves accessibility but also transforms the look of your property. Once complete, we’ll fit a brand-new, fully insulated double garage door that complements your home’s design.
Benefits of Converting Two Single Garage Doors into One Double Door:
Better Access & Usability: A wider entrance makes parking larger vehicles much easier.
Modernised Appearance: Creates a cleaner, more cohesive front-of-house look.
More Usable Space: Removing the centre column gives you greater flexibility for storage or workspace.
Added Property Value: Professionally executed conversions are a smart investment for resale potential.
It’s not just garage conversions — we also undertake a full range of structural opening projects across St Albans.
Whether you’re replacing an old timber door or window frame that supports brickwork, or you want to enlarge or relocate an opening entirely, we can handle it from start to finish. We install steel or concrete lintels where required and ensure all building work complies with structural and safety standards.
If you’re planning to install new patio doors, bifolds, or a feature window, we’ll carry out the necessary calculations and modifications to make your vision a reality.
All work is completed by our own in-house team — we never subcontract — and we remove all waste responsibly once the job is done.
Double garage door conversions
Wall removals for open-plan living
RSJ installations for new openings
Lintel replacements above windows or doors
Widening or altering existing openings
Structural repairs and reinforcements
Local & Experienced – Trusted across St Albans and Hertfordshire for quality workmanship.
Qualified & Insured – All RSJ and load-bearing work carried out to building control standards.
End-to-End Service – From design and calculations to completion and disposal.
Transparent Pricing – Clear quotations and no hidden extras.
Minimal Disruption – Clean, efficient, and respectful service in every home.
If you’re based in St Albans or the surrounding areas then get in touch for a free, no-obligation site survey. We’ll assess your structure, discuss your plans, and provide a clear quotation tailored to your property.
Contact Us Today
Transform your space with trusted structural alteration specialists in St Albans. Call 01442 388955, email info@sdmdoors.co.uk, or book your free survey online.
Yes. Any work that affects a load-bearing wall, structural beam, or changes the use of a space (like converting a garage into a room) must comply with building regulations. We handle all building-control liaison, ensuring your project meets safety and structural standards.
An RSJ (Rolled Steel Joist) is a steel beam installed to support the load above an opening once a supporting wall or pier is removed. It provides crucial strength and stability for structural alterations such as garage conversions or creating open-plan layouts.
Absolutely. Our qualified structural engineers calculate the correct beam size and load distribution before any work begins. We use acrow props, strongboys, and precise installation methods to guarantee structural integrity throughout the project.
Yes, in most cases it will. A wider, modern double garage is more practical, visually appealing, and desirable to buyers. It can also improve kerb appeal and make everyday use of your property more convenient.
Timeframes vary depending on the project size, but a standard double garage conversion usually takes 5–10 working days from structural work to final finish. Smaller alterations like a new lintel or wall removal can often be completed in 2–4 days.
Yes. We provide free, no-obligation site surveys across St Albans and nearby areas. We’ll assess your existing structure, discuss your goals, and provide a detailed written quotation with all costs clearly outlined.
Yes, we remove and responsibly dispose of all debris, brickwork, and waste generated during the project — leaving your property clean, tidy, and ready to enjoy.
Yes. We carry comprehensive public liability and structural works insurance, giving you complete peace of mind throughout your project.
We’re based near St Albans and cover the surrounding areas including Sandridge, Wheathampstead, London Colney, Watford, Hemel Hempstead, Hatfield and further afield.
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