Fire Door Gap Gauge - Door Tolerance Check

Accurately checking fire door gaps is one of the most common parts of a fire door inspection.

This Fire Door Gap Gauge is a simple tool used to measure the gap between the door leaf and frame, helping you identify whether gaps fall within commonly expected tolerances.

Fire Risk Assessments (FRA) frequently identify excessive or inconsistent gaps as defects. Using a gauge removes guesswork and allows checks to be carried out consistently.

What it helps you check

• side and head gaps
• threshold gaps
• consistency around the door

Why a gap gauge is useful

Gap size is difficult to assess visually.

A gauge allows you to:

• check gaps quickly during routine inspections
• identify doors that may require adjustment
• support consistent inspection records
• avoid relying on subjective judgement

Typical use

• routine fire door checks
• inspection programmes
• pre-FRA internal checks
• confirming remedial works

Application

Insert the gauge between the door leaf and frame at multiple points to check for consistency.

Note

Gap tolerances may vary depending on the door design, seals and installation. Always consider the Fire Risk Assessment and door specification when interpreting results.