An L shaped loft conversion joins two dormers together: one on the main roof and another on the roof of the rear extension, often called the outrigger. Together they form an L shape that creates a large, flexible space, often big enough for two bedrooms or a bedroom with a generous en-suite.
At ST Lofts, L shaped conversions start from around £39,600 for a smaller loft. Because they usually create a lot of floor space, most finish well above that, so the best way to see a figure for your own home is our loft conversion cost calculator.
The cost calculator gives you a guide price in minutes. For an exact price, book a free survey. We’ll come out, look at your loft, talk through what you’d like and then send you a full, itemised quote.
There’s no obligation, and if you’d rather talk it through first, give us a call or send us a WhatsApp.
Our L shaped price covers the complete build. That typically includes building both dormers, the structural steelwork and floor joists, roofing and cladding, windows, insulation, a new staircase, electrics, plastering and building control sign-off.
It’s one of the larger loft conversions we carry out, and most take around nine to twelve weeks on site.
The main things that affect the cost of an L shaped conversion are:
L shaped conversions suit Victorian and Edwardian terraces with a rear outrigger, which are found right across Bristol in areas like Bishopston, Southville, Bedminster and Totterdown. If your house has a two-storey back addition, an L shaped loft can make the most of it.
They often fall under permitted development, but planning permission is usually needed in conservation areas. Read our guide to party walls and loft conversions if you live in a terrace.
Velux Loft Conversion Cost
From around £30,000
Dormer Loft Conversion Cost
From around £40,300
Hip to Gable Loft Conversion Cost
From around £42,000
Mansard Loft Conversion Cost
From around £37,400
Not sure which type suits your home? Our cost calculator lets you compare all five side by side.
Our free online calculator gives you an instant price for a l shaped loft conversion based on the size of your loft, with options for an en-suite, extra windows and more.
When you’re ready, we’ll arrange a free, no-obligation survey and give you a full, itemised quote.
Common questions about the cost of a l shaped loft conversion.
L shaped conversions with ST Lofts start from around £39,600 for a smaller loft, with most finishing higher because of the extra floor space they create. Use our cost calculator for an instant price for your loft.
It’s two dormers joined together, one on the main roof and one on the rear extension roof, creating an L shaped room or rooms with full head height.
Mainly terraced and some semi-detached houses with a rear outrigger, which are very common in Bristol.
Most take around nine to twelve weeks on site, depending on the size and layout.
