Guides
How openings actually perform.
Short, practical explanations of the parts of a Division 8 opening that decide whether it works — written for the questions we get asked most often on real projects.
These explain the mechanism — what a component does and why it matters — rather than reproducing performance figures. Certified data belongs with the manufacturer who tests and maintains it, so every guide ends by linking to the factory's current documentation. That way the reasoning here stays true and the numbers you use stay live.
- For specifiers, estimators and project managers
Sealing a fire-rated opening
“The door is rated — so why does the perimeter matter?”
A fire door is certified as an assembly, not as a leaf. What happens at the gap around it decides whether the assembly behaves the way it was tested to, and it is the part most often changed in the field.
- For specifiers and project managers
What actually drives acoustic performance
“We specified an acoustic door. Why is the room still noisy?”
Sound follows air. A door leaf chosen for its acoustic construction will still underperform if the perimeter leaks, and the gap under the door is usually the largest leak in the assembly.
- For specifiers, estimators and project managers
Solid core wood or hollow metal?
“Which one belongs in this opening?”
The two dominate commercial work for different reasons. The choice usually comes down to what the opening has to survive, what it has to look like, and which decisions you can afford to leave until site.
Not covered here?
Ask the question directly.
If the opening you are working on raises something these do not answer, that is the more useful conversation — and it is the one worth having before the schedule is fixed rather than after.
Specifying a Division 8 opening? Talk to a specialist.
Technical support for specifiers, fast accurate quoting for estimators, and factory-direct training for your team.