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SIDERISE MI Mullion and Transom Inserts for Curtain Walling (formerly Lamaphon Mullion / Transom Inserts)

Siderise Group

SIDERISE MI consists of a range of specialist mullion and transom inserts designed to improve the sound insulation performance of lightweight hollow framed facades or glazed areas.

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+44 (0)1656 730833 www.siderise.com

SIDERISE Mullion and Transom Inserts comprise a range of specialist material components intended to improve the sound insulation performance of lightweight hollow framed facades or glazed areas. Whilst the inserts may be employed for the purpose of improving the sound transmission characteristics of the building envelope (e.g. outside to inside performance), more commonly they are used to assist in reducing flanking transmission between adjacent internal areas. This includes ‘room to room’ and ‘floor to floor’ flanking sound transmission. Specific optimal solutions have been developed for each of the common conditions encountered in curtain wall constructions. The design of the appropriate insert considers not only acoustic performance but also ease and practicality of installation. In-house manufacturing techniques such as CNC/ die cutting or routing permits an accurate tailored fit within the particular hollow frame element.

SIDERISE AVC Mullion Closures:

Die-cut parts in a dense resilient foam material with a central flexible heavy membrane. Usually die-cut to the exact internal profile of the hollow frame section. Depending on the sound insulation performance required they may be deployed singly or in pairs.


Shaped composite high mass layer and acoustic foam inserts. Comprises a layer of V Foam with a 10 kg/m² limp elastomeric barrier membrane to one side. Fitted in pairs in a back-to-back arrangement with the barrier layers to the outside.


Shaped resin bonded rock fibre absorptive inserts.

SIDERISE V Foam Baffles:

Shaped impregnated acoustic foam absorptive insert baffles, typically in 300–600 mm lengths and are usually installed centred on the midpoint of the compartment line.

SIDERISE V Foam Inserts:

Shaped impregnated acoustic foam absorptive inserts. Robust, flexible and dust free.

Features and benefits:

  • Excellent acoustic performance.
  • Custom dimensions and shapes.
  • Simple to install.
  • Wide range of base materials.

General information

Carbon Impregnated Foam & Polymeric Barrier


Carbon Impregnated Foam

Foil Faced Polymeric Barrier and Carbon Impregnated Foam


Made to specification

Uniclass 2015
Pr_35_93_13_80 Sound attenuator infill unitsPrimary
Specification data - Sound attenuator infill units
Product Reference

AVC Mullion Closures

'Along' frame section treatment.

HB Inserts

'Through' frame section treatment.

MF Inserts

'Through' frame section treatment.

V Foam Baffles

'Along' frame section treatment.

V Foam Inserts

'Through' frame section treatment.

Digital objects
PlatformCompatibleVersionCertified to
IFC2X3 2 1.3
Revit 2016 3 2.0
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