As-built drawings of a London house or flat cost £395 with us, plus £150 for the laser survey they are drawn from. That gives you floor plans, elevations and sections of the building as it actually stands, at a stated scale with a north point. There is no separate "as-built" product because that is exactly what our existing drawings are: a record of what is there today, not of what was meant to be built.
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What changes from job to job is what the drawings are for. Tell us that first, because a lease plan, a set for a buyer's solicitor and a base for the next extension each need slightly different sheets.
What is an as-built drawing?
A drawing of the building after the work, made by measuring it. Builders rarely follow approved drawings to the millimetre. A beam is moved, a window is widened, a partition shifts to fit a boiler. The approved drawings then describe a house that does not quite exist. As-built drawings close that gap.
They are not a check that the work complied with anything. They record dimensions, not quality, and they do not replace a completion certificate or a planning decision.
Who asks for them, and why?
Building control at completion. Under the Building Regulations, a completion certificate is given within eight weeks of the completion notice once the authority is satisfied the work complies (regulation 17). Where the finished work differs from the full plans that were checked, the inspector may ask for amended drawings. As-built drawings answer that.
A buyer's solicitor or lender. When you sell, the buyer's solicitor compares the house with its planning and building control history. A clear as-built set showing the extension as it stands helps them match it to the approved drawings. It does not cure a missing approval.
A lease plan for a flat. If you are granting or extending a lease, HM Land Registry has its own rules for the plan. Its guidance asks that a plan shows a north point, is based on a metric scale with a bar scale, and identifies the floor levels included (HM Land Registry). It also asks that the plan is not endorsed "Do not scale" and ideally is not marked "for identification only". We draw to those rules when you tell us it is for a lease. The red edging around the demise is for your solicitor to confirm.
The next project. Anyone planning a loft after a rear extension needs the house as it now is. Planning drawings must be at an identified scale and show north (MHCLG), and the proposed set is drawn on the existing one. An as-built set from this year saves a second survey later.
A landlord's licence. Selective and HMO licences need floor plans to each council's own rules. That is a different service, covered in our selective licence floor plans post.
What do I get for the fee?
The existing drawings service produces floor plans of each level, elevations of each side, and sections where heights matter, all at a stated scale with a north point and a scale bar. They are issued as PDF. If you need CAD files for a builder or a later designer, ask when you book and we confirm at the quote stage.
The measured survey is the visit itself: laser measurements inside and out, usually done within five working days. See what a measured survey costs for what it records.
If you send us the approved drawings, we can note on the as-built set where the building differs. Whether that difference needs any action is a separate question, covered below.
What if the work was never signed off?
Then as-built drawings on their own are not the answer. If building control never issued a completion certificate, the route is usually a regularisation application to the council. That needs a survey of the work, drawings and a specification, and often some opening up so the inspector can see hidden work. Our regularisation drawings service covers it and costs from £615 drawings + £150 survey (£765 total). The council's regularisation fee is paid to the council.
If the problem is planning, not building control (an extension built larger than approved, or without permission), the route is a retrospective planning application or a certificate of lawfulness. As-built drawings are part of either, but the application is the product.
It is worth knowing which case you are in before you pay for anything. Send us what paperwork you have and we tell you which service fits.
How do I get the right set first time?
Three things decide what goes on the drawings, and each saves a revision later:
- The purpose. A lease plan needs each floor level identified and the demise clear. A set for building control needs the sections where the work was done. A base for the next project needs the roof and the garden levels.
- The approved drawings. If planning or building control drawings exist, send them. We draw the same sheets at the same scale, so anyone comparing the two can lay one over the other.
- Access. The survey records only what we can reach. A locked loft or a shed full of furniture becomes a gap on the drawing, so clear what you can before the visit.
Does a flat cost less than a house?
Our published prices are fixed, not per square metre. A one-bedroom flat and a three-storey terrace are both £395 for the drawings and £150 for the survey. If a property is unusually large or complex, we tell you before the visit. For a lease plan of a flat, we survey what you control and record shared parts as far as they can be seen.
Frequently asked questions
Can you draw as-built plans from the approved drawings without visiting? No. The point of an as-built set is that it records what was built. Copying the approved drawings would repeat any changes the builder made without showing them.
Will as-built drawings help me sell? They can help a buyer's solicitor understand the house. They do not replace planning permission, a completion certificate or a lawful development certificate if one of those is missing.
Do estate agents need as-built drawings? An agent usually commissions its own marketing floor plan. That is a different thing, as our post on estate agent floor plans explains, and it is not drawn to a stated scale.
How long does it take? The survey is usually within five working days. We give the drawing time with the quote, because it depends on the size of the building.
