Design & Build
Basement Conversions in North London & Enfield
On a tight London plot, the space under your house can be the cheapest room you never knew you had. We convert cellars and dig out full basements, waterproofed and structurally sound, into rooms you would never guess were below ground.
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Cellar conversion or full dig-out
If you already have a cellar, converting it is the quickest win: tank it against water, improve the head height where we can, and finish it as a room. Where there is no usable void, a full dig-out with underpinning creates a whole new floor, ideal on the terraces and semis where you cannot extend out or up any further.
Waterproofing done properly
A basement lives or dies by its waterproofing. We design to the right standard with tanking, cavity drainage and a sump where needed, so the space stays dry for good, not just for the first winter.
Light, air and a real room
Lightwells, sun pipes and proper ventilation turn a basement from a dark store into a genuine living space, a media room, gym, office, utility or guest suite.
Basement Conversions by area
Helpful guides
Frequently asked questions
How much does a basement conversion cost?+
Converting an existing cellar in our area typically runs from around £1,500 to £2,500 per square metre, while a full dig-out with underpinning costs considerably more. Our estimator gives a tailored figure in about a minute.
Do I need planning permission for a basement?+
Converting an existing cellar is often permitted development, but lowering the floor or a full dig usually needs building control, and sometimes planning and party wall agreements. We check and handle all of it.
Will a basement stay dry?+
Yes, when it is waterproofed properly. We design tanking and cavity drainage to the correct standard with a sump and pump where needed, so it stays dry long term.
Which areas do you cover?+
We cover Cheshunt, Cuffley, Goffs Oak, Enfield, Hoddesdon, Broxbourne, Waltham Cross and across Hertfordshire and North London.
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