Convert an existing cellar, or create genuinely new space below ground.

Very different. Converting an existing cellar with no external alteration is generally internal work, which isn't development and doesn't need planning permission - though Building Regulations still apply. Excavating a new basement where none exists commonly needs planning permission, often because of its effect on the external appearance of the property or on neighbouring structures. We'll be clear from the outset about which situation applies to you.

Waterproofing to BS 8102, ceiling height, ventilation, and a means of escape in a fire (Part B) are the main areas, and they apply whether you're converting an existing cellar or building new - the planning answer and the Building Regulations answer are separate questions.

Genuinely usable below-ground space can add both floor area and value, but the uplift depends on your local market, how the space is finished, and whether it's counted as habitable accommodation. It's not something we'll put a specific figure on without knowing the property and area.

Yes, subject to planning permission where it applies, Building Regulations approval, and (for terraced or semi-detached properties in particular) a party wall agreement with any adjoining owners, since excavation work is very likely to affect a shared structure.

We currently work across the North West.

The business was created from an existing property development background, so the trades, supplier relationships, construction experience and project management infrastructure already exist. That's what allows a project to be properly organised before it starts, rather than assembled on the fly.

It depends entirely on the type and scale of project. We publish industry cost ranges with visible sources on our cost guides for extensions, loft conversions, garden rooms, garage and basement conversions, kitchens and bathrooms - a genuine starting point for budgeting, not a quote for your specific property.

It depends on your local property market, the size of the move you'd otherwise need to make, and moving costs (stamp duty, agent fees, legal fees) versus construction costs. Extending is often - though not always - the more cost-effective way to gain space if you're happy with your current location.

Get in touch and tell us about your project - we'll talk through what's realistic for your property before any commitment is made.

Use our project finder or contact form to tell us what you're thinking, or try one of our free tools - the project matcher, the permitted development checker, the extension size visualiser or the cost estimator - to get a first steer before we talk.