Preventing unwanted noise transfer between attached dwellings is one of the most critical design considerations in new-build housing and apartment developments. Regulation 41 of the Building Regulations allows sound performance compliance to be demonstrated in one of two ways:

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1. Pre-completion sound testing, or

2. Using registered design details published by Robust Details Ltd (RDL).

 

For developers who want certainty, speed and reduced risk of remedial work, Robust Details (RDs) offer a proven, fully approved alternative. Cellecta provides a range of acoustic floor solutions designed for use within approved Robust Detail constructions.

Robust Details are pre-tested, high-performance separating wall and floor constructions that exceed the minimum acoustic performance standards required under Part E – Resistance to the Passage of Sound.
 
When you register your plot(s) with RDL and construct strictly to the chosen RD specification, you do not need to complete pre-completion sound testing.

Key Features

• Only applicable to new-build houses and purpose-built flats.

• Must be registered before work begins on site.

• Building Control bodies accept RD documentation as proof of compliance.

• Construction must follow the RD Handbook exactly, including correct materials.

 
Guaranteed Approach
With pre-approved designs, acoustic performance is assured as long as construction follows the RD specification.
 
Avoid Costly Delays
Pre-completion testing introduces risk: if a wall or floor fails, remedial work and retesting can halt handovers and disrupt construction programmes.
 
Clear Construction Guidance
The RD Handbook and site checklists provide practical, buildable detail guidance designed to achieve consistent performance.

Accepted by All Building Control Bodies
Local authorities and Approved Inspectors recognise RD documentation as an approved compliance route.

Robust Details do not apply to:

• Conversions and material change of use projects

• Renovations, extensions, or buildings where existing external walls form part of the separating structure

• Dwellings where construction has already commenced before registration

For these scenarios, early agreement with Building Control is essential and pre-completion testing may be required.

To use Robust Details, the following actions must be completed before any building work starts:

 

STEP 1 – Confirm the Appropriate Robust Detail

Using the RD Handbook, identify the separating wall or floor type suitable for your design. Ensuring compatibility with the substructure (including foundation type) is essential.

 

STEP 2 – Complete a Plot Registration (RD110 Form)

Submit an online application or RD110 form for each plot where a Robust Detail will be used.

 

STEP 3 – Receive RDL Registration Documentation

RDL will issue:

• Purchase Statement (with unique reference numbers for each plot)

• RD checklists for site verification

• Compliance Certificates

• Invoice and covering letter

 

STEP 4 – Notify Building Control

Before commencing work, submit the Purchase Statement to the local authority or Approved Inspector.

 

STEP 5 – Confirm Acceptance

Ensure Building Control has formally acknowledged the notification before construction starts.

Your notification must clearly state:

• The part(s) of the building where the RD will be used

• The specific Robust Detail reference selected

• The unique RD reference number from your Purchase Statement

Incomplete notifications may invalidate your use of Robust Details and require mandatory sound testing.

Once registered, the responsibility lies with the developer and contractor to:

• Build to the exact RD specification

• Use only the materials listed in the RD Handbook

• Avoid common installation errors (e.g., bridging resilient layers, incorrect block densities)

• Follow RDL checklists during each build stage

• Invite Building Control for agreed inspection points

Failing to meet RD requirements during construction can revoke the RD exemption and trigger required sound testing.

RDL monitors the performance of RD constructions through:

• Feedback from Building Control bodies

• Input from new home warranty providers

• Independent acoustic spot checks (testing and visual inspections)

This ensures the RD scheme continues to meet and exceed acoustic performance standards.