An open plan ground floor means taking out one or more internal walls and carrying what they held on a beam. GS Renovation does that work in Potters Bar to a structural engineer's calculations, then handles the making good, the flooring and the finishes. A full knock through, including the wall removal, the engineer's fee and making good, is put at £2,500 to £6,500 and above by indicative London ranges, MyBuilder and Checkatrade, 2026.
Does opening up a ground floor need planning permission
Internal changes do not. The Royds design guide lists internal changes, along with new windows, front doors, repainting and like for like small scale repairs or maintenance, as alterations that do not require planning permission in the Royds Conservation Area. Building regulations approval is the requirement instead, and that is where the beam design is examined.
The answer changes as soon as the footprint changes. If the plan involves extending, or altering anything visible from the road, the planning position is checked before the structural design is commissioned.
Opening up a Royds bungalow
It starts with knowing which house type you have. The original Hicks brochure records five principal house types on the Royds estate. They run from semi detached two bedroom bungalows and semi detached three bedroom bungalows, through detached two and three bedroom bungalows, to detached semi bungalows with two or three rooms upstairs.
That distinction decides the beam. A single storey roof and a storey and a half roof load the ground floor walls in different ways, and the temporary support has to suit whichever you have. We open up, have the engineer look at what is actually there, and price against the calculations rather than the floor plan.
What building control looks at, and where an extension changes it
Structural beams and openings are on the list. Hertfordshire Building Control lists the matters its inspectors examine as foundations, ground and floors, damp proofing, roof structure, drainage, structural beams and openings, fireproofing and thermal insulation. An open plan conversion touches several of those at once when it is combined with a rear extension.
In a conservation area the extension thresholds bite first. The Royds design guide sets out the conservation area position. In any conservation area, planning permission is required for a single storey rear extension over 3 metres deep on a semi detached or terraced house. On a detached house the depth trigger is over 4 metres. In either case the extension also has to be more than 4 metres in height for that to apply.
- Heat loss and acoustic considerations before the wall comes out
- Lighting, heating and electrical reconfiguration
- Flush beam detailing where a downstand would look wrong
- Utility and boot room space carved out of the new layout
- Steel beam installation to remove the dividing wall
The GS Renovation Difference in Potters Bar
Open plan work runs across every trade in the house, so we keep it under one contract. The structural engineer we appoint sizes the beam, we build to the calculations, and the same team carries on through the plastering, the flooring and the decorating. There is no handover in the middle where a job stalls. You have one point of contact throughout, and GS Renovation Ltd is fully insured and rated 4.9 from 31 reviews on MyBuilder.
- Photographs kept at each stage for your records
- Dust screens and floor protection in occupied homes
- One point of contact on the phone, not a call centre
- The layout planned around how you actually use the ground floor
- Cooking smells and extraction planned into an open kitchen
- Lighting circuits zoned rather than one pendant in the middle