ᐅ Seal the joint in the masonry

Created on: 23 Aug 2012 03:00
-
-
H
HerrNolte-1
23 Aug 2012 03:00
Hello,

how is a masonry joint properly sealed? Does the width matter? Are there alternatives to mortar? I’m unsure how to fill a deep but very narrow joint with mortar. Specifically, it concerns the joints between the reinforced hollow core partition walls and the exterior walls. The joints extend over the full room height.

Good luck HerrNolte
M
MODERATOR
31 Aug 2012 23:02
This type of joint is usually left open—at least not filled with mortar—because that would weaken the sound insulation between the two buildings. Mortar, being a relatively rigid material, would transmit structure-borne sound from one partition wall to the other.

A partition wall joint can be professionally sealed using a special silicone sealant applied over a backing material (not recommended for amateurs), or a panel material can be installed on one façade covering the entire height of the joint evenly (do not fix it to both façades, as this would again cause sound transmission). A metal sheet about 10cm (4 inches) wide, fiber cement board, or plaster carrier board (which can be plastered over) would be suitable for this purpose.