Site survey: 8 measurements to take so you don't come back

You've already driven 40 minutes. The client "has the measurements": 12'6" by 13'9", written on a pizza box. On site, the 12'6" is skirting to skirting, the floor isn't level, and nobody measured the window sill: yet they want a cabinet under the window. You go home, you price it, and you come back "just for the sill height." That's the second unpaid visit.

A site survey is not an architect's drawing. It is a list of 8 measurements homeowners almost never take, plus the assumptions to put on the quote. Without that, you are pricing photos. With it, you only return if the job signs.

Amounts cited are indicative ballparks. Download the PDF checklist to run the same process on every visit.

Why the client's survey is never enough

Even a careful client measures their room: wall to wall if they read a guide, often skirting to skirting otherwise. They almost never measure:

• partition thickness and type;
• floor level change;
• window sill height;
• real waste-pipe axes (not "the sink is on the left");
• access for debris.

That isn't bad faith. It's your job. The homeowner brief (see the mirror Measure your room: 8 dimensions) is for qualifying the project. The site survey is for locking the price. They complement each other; one does not replace the other.

Example: 48 sq ft bathroom, client says "6'11" × 7'1"." You measure 6'10" × 7'0" internal faces, ½ inch fall towards the door, sill at 42". The 32" tray they planned no longer fits with a door swinging in. Found after the order, that's a change order and an angry client. Found on the visit, that's one sentence on the quote.

The 8 measurements to take on site

Keep the same order on every job: the sheet is built for that.

1. Confirm the client's sizes, then write yours as assumptions. Don't throw their notebook away: measure over it, note your internal faces, and put on the quote: "surfaces used: 47 sq ft floor, ceiling 8'3"." If it moves, it's a change order, not a fuzzy memory.
2. Partition thickness and type. Plasterboard, brick, unknown. A 2" stud wall does not take the same water feed as a 6" masonry wall. If you don't know, write "type not verified: assumed plasterboard."
3. Floor level change and flatness. Especially bathrooms and kitchens. A laser or a 6-foot level. More than 3/16" per 3 feet: levelling compound or extra-low tray to decide now.
4. Sill height of every window. The dimension that decides cabinets, radiators, worktops. Clients almost never take it: that's reason #1 for "I'll pop back."
5. Services, from a reference corner. Water, waste, electrics, gas, ventilation. Distances to the inch from a marked corner. Photo of the meter and the riser. Moving a waste 6 feet is often £300-600: either it's in the quote, or it's excluded in writing.
6. Access for debris and materials. Floor, landing, hoist, parking, permitted hours. A 4th floor with no lift is not "as usual": it's 10-15% extra labour on heavy items, or a skip + handling as a separate line.
7. Substrate condition. Moisture, cracks, tile on plaster, leak stains. Photo + one assumption line: "sound substrate assumed; moisture found → waterproofing change order."
8. Meters, risers, common areas to protect. What the client doesn't photograph because "that's not the room." That's a £250-400 "protection + clean" line… or a silence the competitor didn't price either, which blows up mid-job.

What goes on the quote, not just in the notebook

A survey that stays on your phone does not protect you. Four lines at the top of the quote are enough:

• surfaces and ceiling height used;
• assumed substrate condition;
• access conditions;
• discoveries (moisture, non-compliant pipework) → written change order before work starts.

Same reflex as framing a client with no brief: what isn't written will be decided against you. See also how to handle a client without a brief.

How Kodarch can help

The guided survey is built for this: each wall's dimensions, openings, constraints, tagged photos, and a plan you can send back instead of a WhatsApp sketch. Fewer "I'll come back for the sill," fewer forgotten assumptions. If the prospect is too early, point them to the simulator and the homeowner sheet; the ones who return arrive with dimensions. See Kodarch for contractors.

Common mistakes to avoid

• Trusting the client's notebook without remeasuring internal faces.
• Keeping the sill height "in your head" to copy at the office: it won't still be right.
• Photographing details (tap, crack) without a full wall to recover scale.
• Pricing access "as usual" on a 5th floor with no lift.
• Leaving partition type implicit: the client's plumber will ask too late.

Frequently asked questions

The client already has a Kodarch plan: do I still remeasure? Yes, internal faces and sills. The plan is the shared baseline; the visit confirms. Write the gap if there is one.

Laser or tape? Laser for ceiling height and long spans, tape for sills, thicknesses and nearby axes. The tool matters less than writing it down.

How long for the 8 measurements? On a simple room, 15-20 minutes once the habit is in. Cheaper than a second trip.

What if I find a level problem too late? That's too late. That's why the assumption line exists: without it, levelling becomes a fight; with it, a planned change order.

In short

The client brief qualifies; the site survey locks the price. Eight measurements (confirmed sizes, partitions, floor, sills, services, access, substrate, common areas) and four assumption lines on the quote. You price once. You only come back to sign.