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Call us on 0208 123 9710 | Email us at info@soundstop.co.uk
Call us on 0208 123 9710 | Email us at info@soundstop.co.uk

Monarfloor Tri-Deck - 10 Boards minimum


  • Superior performance

  • 2400mm x 600mm Flame retardant boards

  • Direct to Joist Application

Reduces sound transmission when existing timber floors will be removed but access to work on the ceilings below is restricted.

For further information, stock availabilty and to place your order, please contact our team.

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Monarfloor Tri-Deck reduces sound transmission through timber party floors where the existing timber deck will be removed but access to work on the ceilings below is restricted.


Given enough mass on the ceiling below ( eg lath and plaster) the use of Trideck alone can be enough to achieve regulation E. This is of particular interest if access to the underlying ceiling is restricted or the underlying ceiling has ornate cornicing or coving which is preferred left untouched.



If you are looking for a product to fit on top of an existing floor without having to remove it, then consider our slimline Monarfloor Deck 9 solution, or our high-performance Monarfloor Deck 18 solution.

Product Application

Unlike the other monarfloor decking systems this can be applied direct to joist so reducing the floor height build up. The product is normally used in conjunction with 45 or 60kg/m3 mineral wool. (100mm) between the joists, meaning no need for an acoustic ceiling.

Features & Benefits:
  • Direct to Joist Application
  • Applications for existing timber floors
  • No need for an acoustic ceiling
  • Supports floor loadings as defined in BS EN 1991-1-1:2002 +A1 2010 (Eurocode 1) which stipulates floor loading of 2 kN
  • BBA Certified
  • Flame retardant
  • Superior performance – the recycled Low Resonance Acoustic Chip (LRAC) foam used has excellent impact improvement characteristics and superior stability within a single layer
  • Dimensions: 35mm x 600mm x 2400mm
  • Weight: 30.5kg per sheet (21.2kg per m2)

Tiling on Top of Overlay Systems

We advise you follow the guidance issued by the Tile Association in dealing with floating floors, which is:

  • Adhesives and grouts must be suitable for floating floors. There are various systems depending on the individual manufacturers detailing.
  • Proprietary tile boards or ply, can be overlaid to provide additional water tightness, and or stiffen the floating floor. These must be bonded.
  • Tiles should ideally be porcelain. We do not advise thick heavy tiles, such as marble, as they are more susceptible to fracture.
  • Tile format must be kept as small as possible (600 x 600mm max). We would advise 450mm x 450mm.

You should also speak to the adhesive manufacturer that is being used as they all have specific detailing to their own products.


Here are the main details for this product:

Dimensions: 2400mm x 600mm

Thickness: 35mm

Pack Size: 10 Board Minimum

Weight: 30.5kg per Board

Density: TBC

Coverage: 1.44 sqm

Fire rating: Flame retardant

Visit our Fitting Instructions section for more detailed instructions relating to your specific application.

Please contact our team if you have any questions on this product.

Looking for a complete soundproofing solution?

If your looking for soundproofing for a particular situation or application, then the best place to start is with our soundproofing solutions that cover walls, floors, ceilings and reducing echo. Select the relevant application below to find out more.

Wall Solutions

Floor Solutions

Ceiling Solutions

Echo Solutions

Instructions for use

Monarfloor Tri-Deck should be laid directly onto the joists in a broken bond pattern with all joints glued and  perimeters flanked.


Diagram Key:

1. Acoustic Flanking Band – reduces impact vibration transmission via party and flanking walls and assists in reducing airborne sound paths

2. 100mm 45kg/m³ insulation

3. 22kg/m² double boarded ceiling on resilient bars perpendicular to joist direction

4. Monarfloor Tri-Deck system

Installation at a glance

  • Flank all perimeter with Monarfloor Flanking Band
  • Level the sub-floor to the required tolerance
  • Lay Monarfloor Tri-Deck platform floor / floating floor system directly over the floor joists in a broken bond pattern with all joints supported and glued
  • Install skirting and trim off excess Flanking Band


Tools & equipment required

  • 1 litre of Monarfloor® Acoustics Adhesive for every 21.5m2 of deck (approx). Note: Adhesive should be applied in well ventilated rooms
  • 1 linear metre of Monarfloor Flanking Band for every 1m2 of flooring
  • Utility knife and straight edge
  • Joinery hand/power tools

Check sub-floor is suitably prepared

  • Ensure the surfaces are structurally sound, clean and dry
  • All internal partitions should be installed and built of the joists
  • Kitchens and bathrooms should also be built of the joists (see Monarfloor Generic Kitchen & Bathroom Detail Drawings)
  • Ensure the correct mineral wool insulation has been packed tightly between the floor joists
  • Support the ends of boards with noggins if required

Tiling on top of Monarfloor

We advise you follow the guidance issued by the Tile Association in dealing with floating floors, which is:

  • Adhesives and grouts must be suitable for floating floors. There are various systems depending on the individual manufacturers detailing.
  • Proprietary tile boards or ply, can be overlaid to provide additional water tightness, and or stiffen the floating floor. These must be bonded.
  • Tiles should ideally be porcelain. We do not advise thick heavy tiles such as marble etc as they are more susceptible to fracture.
  • Tile format must be kept as small as possible (600 x 600mm max). We would advise 450mm x 450mm.

You should also speak to the adhesive manufacturer that is being used as they all have specific detailing to their own products.

Care of materials

Materials must be kept in a dry storage area at all times.

Working Safely

  • Working on any building site can be a hazardous activity. Only suitable persons having appropriate competence, training and physical fitness should be allowed onsite.
  • Personal Protective Equipment (PPE) must be worn at all times.


Visit our Fitting Instructions section for more detailed instructions relating to your specific application.

Check out our Soundproofing Guides for more information, advice and tips on all aspects of soundproofing.