Technical

What Happens During a Site Survey? | Homeowner Guide

By John · 24 March 2026

Types of Site Survey

What Happens During a Site Survey? | Homeowner Guide matters most when a homeowner is close to making a decision and does not want a vague quote, soft assumption, or missing line item to become an expensive problem later.

Builder's Survey (For Quoting)

Duration: 30-60 minutes

What they'll do:

Measure the existing property.
Assess access for materials/equipment.
Look at ground conditions.
Check for obstructions (drains, trees).
Note existing construction.
Discuss your requirements.

What to have ready:

Any existing drawings.
Your design ideas/sketches.
List of must-haves.
Access to all relevant areas.

Professional Survey (Pre-Design)

Duration: 1-2 hours

What they'll do:

Full measured survey.
Drainage investigation.
Note construction details.
Photograph everything.
Record levels.

What They're Looking For

Access issues:

How will materials get in?
Space for skip?
Scaffolding positions?

Ground conditions:

Slope of garden?
Signs of drainage issues?
Trees near boundary?

Existing structure:

How is current extension attached?
Cavity or solid wall?
Roof construction?

Hidden problems:

Damp signs?
Structural cracks?
Asbestos materials?

Prepare for the Visit

1. Clear access to all areas. 2. Know where your drains are. 3. Have your drawings/ideas ready. 4. Note any known issues. 5. Ask questions!

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Want a professional assessment? [Get an independent review](/#get-started) from The Building Guys.

Next Step

If you want help applying this to your own project, use the right route below.

Start with [Quick Review](/quick-review) if you want a fast first check.
Use [Builder Quote Review](/builder-quote-review) if you already have a quote in hand.
See the [Sample Report](/sample-report) if you want proof before you buy.

Frequently Asked Questions

Why does site survey extension matter so much?

Because site survey extension often sits right at the point where money, scope, and risk meet. If the paperwork is vague here, homeowners usually discover the problem after they have already committed.

Should I ask the builder more questions before I agree?

Yes. Clear builders should be able to explain what is included, what is excluded, and what assumptions sit behind the price.

Is a quick review enough?

Sometimes, yes. If you only need a first sense-check, start with [Quick Review](/quick-review). If you already have a proper quote or more serious concern, use [Builder Quote Review](/builder-quote-review).

What if I want proof before I buy?

Look at the [Sample Report](/sample-report). It shows the kind of clear, practical output we are aiming to give homeowners before they sign anything.

Practical Questions to Ask Before You Commit

When homeowners are dealing with site survey extension, the safest move is usually to slow the decision down and ask a few direct questions in writing.

What exactly is included in the current price?
What assumptions are being made that could change later?
Which items are still provisional, estimated, or allowance-based?
What would trigger a variation or extra cost?
What needs clarifying before any deposit or approval is given?

Short questions like these often reveal whether the paperwork is genuinely solid or simply looks tidy at first glance.

The Safer Way to Use This Advice

Use this article as a filter, not as a substitute for proper review. If the issue still feels unclear after reading, that is usually the sign that a real second opinion is worth getting.

A Final Word on Site Survey Extension

Site Survey Extension is worth checking before you commit.
A weak decision around site survey extension usually gets more expensive later.
Clear paperwork around site survey extension protects the homeowner, not just the builder.
If site survey extension still feels vague, get a second opinion before money moves.