Do you need planning permission for a knock-through?
Internal knock-throughs rarely need planning permission — but building regs apply to structural walls, and listed buildings and flats differ.
Service
Knock-throughs & structural openings
A knock-through joins two rooms into one — most often the kitchen and dining room, or the front and back rooms of a terrace or semi. We also form new doorways and widen existing openings, including large openings in rear walls for bifold or sliding doors.
Every opening is designed by an engineer and signed off by building control, whether it is a 900 mm doorway or a 5 m opening into an extension.
What’s included
- Kitchen-diner and through-lounge knock-throughs
- New doorways and serving hatches
- Widening existing openings
- Rear wall openings for bifolds, sliders and French doors
- Openings into new extensions
- Blocking up old doorways and openings
Worth knowing before you book anyone
Planning permission
Internal knock-throughs rarely need planning permission. Listed buildings need listed building consent, and flats may need the freeholder's approval.
Pipes and cables
Pipes, cables and gas runs in the wall need rerouting before it comes out. We identify them at the survey so the right trades are booked.
Knock-throughs & new openings: your questions answered
Do I need planning permission for a knock-through?
Usually not for internal walls in a house. You do need Building Regulations approval if the wall is load-bearing, and listed building consent if the property is listed.
Can you form an opening for bifold doors?
Yes. We install the steel lintel or goalpost frame the engineer specifies and leave the structural opening sized to your door supplier's dimensions.
Will a knock-through make a lot of dust?
Cutting masonry is dusty, so the work area is sheeted off, dust extraction is used on cutting tools and the site is cleaned at the end of each day.
Related guides
How much does it cost to remove a load-bearing wall? (2026 UK prices)
Typical 2026 UK prices for removing a load-bearing wall: steel, labour, engineer and building control — and what makes the price move.
Is my wall load-bearing? How to tell (and how to be sure)
How to tell if a wall is load-bearing: joist direction, walls above, spine walls, and the checks a structural engineer makes. When in doubt, get it confirmed.
Where we do this
Knock-throughs & new openings across Knutsford, Wilmslow, Macclesfield, Altrincham, Sale, Stockport, Didsbury & South Manchester, Stretford & Urmston, Warrington, Northwich, Chester, Crewe & Nantwich, Congleton.
Need knock-throughs & new openings?
Send photos or your engineer's drawings for a same-day budget price, or book a free survey.