In order to achieve the designed acoustic performance on site, any air gaps must be eliminated and all components should fit as intended, as any leakage of air will reduce effectiveness– sound is like water – any gaps, even those not visible, and it will leak. The best way to achieve this is with fully engineered, factory finished performance doorsets.

These are supplied with all the necessary seals fitted to either door or frame, and where necessary including astragals for pairs. Test results are generally for single leaf doorsets and a reduction of some 2-3 RwdB can be expected for pairs. It is not practicable to seek useful sound reduction levels from double action doors as these are difficult to seal at the foot of the door.

With acoustic doors the gap between door and floor must also be sealed with contact or wiping seals.

Thresholds will also be needed and these must be level with the door. They must be bedded on mastic and screw-fixed direct to hard surfaces, whilst carpet and textured flooring should stop either side of the threshold. Low profile aluminium thresholds may be fixed on a hardwood packer which should be located on the slab, splitting any carpet or textured flooring, this will ensure the threshold is above the floor finish again ensuring that there is a mastic seal between each element.

Gaps between back of frame and wall should be completely packed with mineral wool and sealed both sides with mastic to a depth of at least 10mm. Special care is needed to check that doors close correctly all around, noting a slight resistance when the door closes against its seals.