What Is a WiFi Site Survey and Do You Need One?

Short answer: a WiFi site survey is a professional assessment of a building's wireless environment. It measures signal coverage, finds interference, tests roaming and validates capacity — so you know how your network really performs, and exactly what to change if it doesn't.

Key takeaways

• A survey measures what your users actually experience, not what access point specifications promise.
• Predictive surveys model a building before hardware is installed; on-site surveys measure a live environment.
• Surveying before deployment is almost always cheaper than fixing coverage problems afterwards.

What a WiFi site survey measures

• Signal strength: how strong the signal from each access point is at every location.
• Signal-to-noise ratio: how much clearer the signal is than the background noise. A strong signal in a noisy area still performs poorly.
• Interference: overlap between your own access points on the same channel, neighbouring networks, and non-WiFi sources such as other radio equipment, found using spectrum analysis.
• Roaming: whether devices move between access points smoothly as people walk through the building.
• Capacity: whether there is enough airtime and throughput for the number and type of devices in each area.

The three types of survey

• Predictive: a software model built from floor plans and building materials, used before installation.
• Passive: walking the site and listening to the wireless environment without joining the network.
• Active: walking the site while connected to the network, to measure real throughput, latency and roaming.

Not sure which you need? Read our comparison of predictive vs on-site surveys.

Signs you need a survey

• Dead zones or inconsistent coverage in parts of your building
• Slow speeds or dropped connections during peak usage
• Devices failing to roam cleanly between access points
• Planning a new wireless deployment, fit-out, or building move

Why survey before you build

A survey before deployment prevents expensive rework — it is always cheaper to design correctly than to fix later. For new builds, a predictive survey models coverage from your floor plans and building materials before a single access point is installed, so you can settle the access point layout and a budgetary bill of materials early.

How long does a survey take?

A typical on-site survey takes 1-3 days depending on site size and complexity. A small office (under 1,000 sqm) can be surveyed in a single day, while a multi-floor building or campus may take 2-3 days. A predictive survey typically takes 2-3 business days after floor plans are received.

What you get back

A proper engineering report includes coverage and signal strength heat maps, interference analysis, capacity planning recommendations, AP placement diagrams with mounting details, channel and power settings, and a prioritized remediation plan with estimated costs. See what to expect from your survey report for a walkthrough.

Titan Grid provides WiFi site surveys in Melbourne and wireless site surveys across Australia, using Ekahau tools.