Quick answer
At minimum, send the site address, a description of what you want built, drawings if they exist, and photographs of the site and its access. The more of the checklist below you can include, the more accurate and firm the resulting quotation is likely to be.
This article is the practical 'what to send' list — for the fuller picture of preparing for a quotation and what makes prices comparable, see How to Prepare for a Groundworks Quotation.
The essentials
Without a location, almost nothing else about a site can be properly assessed — access, ground conditions and nearby designations all depend on knowing exactly where the site is.
The minimum to send with any enquiry
- Full site address and postcode
- A short description of what you want built or done
- Your intended timescale, even approximately
- Whether planning permission is already granted
Documents
Send whatever exists rather than waiting until everything is complete — a partial set of documents with a note on what is still outstanding is more useful than nothing at all.
Documents to attach if you have them
- Architectural drawings (PDF is ideal)
- Planning decision notice and any conditions
- Structural engineer's details, if available
- Drainage layout or strategy
- Any specification document
- Survey reports — topographical, ground investigation, drainage CCTV survey
Photographs
Photographs of the site itself, the access route from the road, gateways and any pinch points, and existing structures are genuinely valuable — often more so than drawings, because they show real conditions that no drawing records: the actual width of a gateway, an overhanging tree, the state of the lane surface, or a visible drainage outlet.
A short video walking the access route and the site is even more useful where access is complicated — it lets a contractor assess turning space and pinch points without needing a separate visit purely to check whether the job is even feasible.
Constraints
Every item on this list can change the method a contractor plans to use, and therefore the price. Flagging them at enquiry stage, rather than letting them surface at the site visit or on day one, saves time for everyone and produces a more reliable quotation.
Constraints worth flagging up front
- Shared access with neighbours or other properties
- Known weight limits on the approach route
- Overhead cables or other overhead obstructions
- Protected trees (subject to a Tree Preservation Order) near the working area
- Neighbouring sensitivities — a shared boundary, overlooking, or a recent dispute
- Livestock on or near the site
- Times of year, or times of day, when work cannot practically happen
What not to worry about
You do not need professionally drawn plans to make an initial enquiry — a sketch, a set of measurements, or even a clear description alongside photographs is enough to start a conversation and arrange a site visit. Formal drawings and engineer's details matter more as a project moves from enquiry towards a firm quotation.
Site-specific information that is easy to forget
Beyond the general checklist, a handful of details are specific to the site rather than the project, and are easy to overlook because they seem obvious to whoever lives there but are invisible to anyone who has not visited.
Site-specific details worth including
- Location of existing underground services, or where the service providers' plans can be obtained
- Whether the site has mains water, electricity and drainage already connected, or needs new connections
- Any known history of flooding, standing water or a high water table on the site
- Presence of septic tanks, soakaways, wells or other buried structures not shown on any drawing
- Whether a topographical survey or ground investigation has already been carried out, even if informally
- Parking and turning arrangements available for a contractor's vehicle during a site visit
Information for extension and renovation projects specifically
An extension or renovation enquiry benefits from a slightly different set of information than a new build, because the existing building constrains almost everything below ground. Sending the existing floor level, damp proof course height and any known drainage runs beneath or near the new footprint, alongside whether the household will remain living in the property during the works, helps a contractor picture how the new work has to tie in rather than treating it as a standalone structure on a clean plot.
For more on how these existing constraints shape the groundworks scope itself, see our guide on what groundworks are required for an extension.
Information for a self-build or new house plot
For a new build on a bare or partly cleared plot, information about the plot's history is as useful as information about the design: whether it was previously built on, farmed, used for storage, or has had any structures demolished on it. Any existing site investigation, even an old one carried out for a previous planning application, is worth sending even if it looks out of date, since it still gives an indication of ground conditions that is better than nothing.
Confirmation of where mains services are proposed to connect, and whether that has already been agreed with the relevant utility companies, also helps a contractor assess how the groundworks package interacts with the wider site strategy.
How the information you send affects the type of quotation you get back
A sparse enquiry — an address and a one-line description — will usually get a response, but it is more likely to come back as a provisional or indicative figure with a site visit needed before anything firmer can follow. A well-documented enquiry, with drawings, survey information, photographs and constraints all set out, allows a contractor to price with fewer assumptions and fewer provisional sums, which generally means fewer surprises once work is under way.
This does not mean every enquiry needs to be perfect before it is sent — it means that the more genuine information is included, the more the resulting figure reflects the real site rather than a set of working assumptions that may or may not hold once the ground is opened up.
Sending information for multiple quotations
Where more than one contractor is being asked to quote, sending exactly the same information to each of them, at the same time, is what actually makes the resulting prices comparable. Sending a fuller set of drawings to one contractor and a shorter description to another means differences between the quotations may reflect differences in the information supplied rather than differences in price for the same job.
Our guide on how to prepare for a groundworks quotation covers this comparison process in more depth, including how to read and compare the prices once they come back.