What this covers, and how it differs from a new stud wall
This service is for upgrading the acoustic performance of walls, ceilings and floors that already exist, adding resilient bar, acoustic quilt and additional plasterboard layers to a party wall, decoupling and boarding out a ceiling, or building up a floor with a resilient layer beneath a floating floor deck or between joists. It's distinct from building a brand new stud partition with acoustic performance designed in from the start, which is a smaller, cheaper job because you're choosing the build-up rather than retrofitting one onto an existing wall with skirting, sockets and a finished ceiling already in place. If you're dividing a room or adding a partition and want it acoustically rated from day one, that's covered under our <a href='/partitions-london'>partitions and stud walls London</a> service, which already treats new acoustic stud walls as standard. This page is for the more common and more awkward job: your wall, ceiling or floor already exists, is already decorated, and the noise problem only became apparent after you or a neighbour moved in.
Airborne noise and impact noise are different problems
Airborne noise is sound travelling through the air and then through a wall or ceiling structure, conversation, television, music. Impact noise is sound generated by something physically striking a structure, footsteps, dropped objects, dragged furniture, and it travels through the building fabric itself rather than the air. A resilient bar and acoustic quilt wall system is excellent at reducing airborne noise between two rooms. It does very little for impact noise coming through a floor from the flat above, because that requires decoupling the floor structure itself, typically a resilient layer beneath a floating floor deck, or an independently hung ceiling below the joists that isn't screwed directly to them. Homeowners frequently pay for a wall treatment when their actual complaint is footsteps from upstairs, which no wall system will ever fix because the noise isn't coming through the wall at all. Getting this distinction right before quoting is the difference between a £900 job that solves the problem and a £900 job that doesn't touch it.
Why London's housing stock fails this way
Victorian and Edwardian terraces built roughly 1850-1910 were never designed with acoustic separation in mind because they were built as single-family houses. When these are converted into two or three flats, which describes a large share of London's rental stock, the wall between the front and back flat on each floor is very often a lightweight stud partition added during conversion, not the original solid masonry, and it can be as thin as a single layer of plasterboard on timber studs with no insulation at all. The floor between flats is usually the original suspended timber joist structure with lath-and-plaster or plasterboard ceiling below, which transmits footfall impact noise extremely efficiently and was never intended to separate two households. Ex-council conversions and purpose-built blocks from the 1960s-80s often have concrete floors, which handle airborne noise better than timber but still transmit impact noise through the slab and, critically, often have poor detailing at the floor-wall junction where flanking transmission bypasses whatever treatment is in the floor itself. 1930s semis split into upper and lower flats sit somewhere in between, generally timber floors with better mass than a stud partition but still no acoustic layer.
What drives the cost
Wall area and number of walls is the starting point, a single 3m x 2.4m party wall runs £700–£1,500 fitted with resilient bar, quilt and double-boarding, while a full room treatment across four walls climbs quickly toward £2,500–£6,000. Ceiling work costs more per square metre than wall work, typically £80–£180 per m2 depending on whether it's a resilient bar overlay or a fully independent ceiling hung on acoustic hangers, because we're often working overhead and sometimes have to take an existing ceiling down first. Floor systems price at roughly £62.50–£87.50 per m2 for a standard resilient-layer-and-floating-floor build in a typical room, but rise to £120–£180 per m2 for a high-spec system with resilient hangers and a fully independent ceiling below, which is often what's needed to genuinely resolve a between-flats noise dispute. Access and disruption add cost, floor and ceiling work in an occupied flat below usually means displacing the room's contents and sometimes arranging alternative access if the flat below is also affected. Electrical work to relocate sockets and switches clear of the new acoustic layer, skirting and architrave replacement once the wall gains 35-50mm of depth, and door and frame adjustment where a wall thickens enough to affect the reveal, are all line items that a vague quote often omits and a proper one itemises.
How long the work takes
A single wall treatment in an occupied room typically takes 2-3 days: first fix (moving sockets, stripping the existing surface), fitting resilient bar and acoustic quilt, boarding with two layers of acoustic plasterboard, then taping and jointing, which needs to dry before decoration. A ceiling treatment adds a day or two depending on whether it's an overlay or a full independent hang, and if the existing ceiling needs to come down first because it's damaged or the room height won't tolerate a second layer, add another day for strip-out and disposal. Floor systems are the slowest, typically 3-5 days for a standard room once you include lifting the existing floor covering, fitting the resilient layer, laying the new floating deck or floorboards, and allowing any adhesive or leveling compound to cure before the finish floor goes down. A full room treatment across walls, ceiling and floor in a home cinema or between-flats dispute commonly runs 1.5-3 weeks. None of these timelines include decoration, which we sequence separately once the acoustic work and any associated plastering has fully dried out.
Regulations and sign-off most homeowners don't expect
Building Regulations Part E, resistance to the passage of sound, only becomes a statutory requirement with mandatory pre-completion sound testing when work creates a material change of use, most commonly converting a house into two or more flats. In that scenario, an approved testing body carries out airborne and impact sound tests on the new separating walls and floors before completion, typically costing £400–£450 plus VAT per pair of tests, with discounts if multiple flats on one site are tested in the same visit. If you're simply upgrading an existing party wall or floor voluntarily, because you can hear your neighbour or you're building a home cinema, there's no legal requirement to test and no Building Control sign-off is triggered by the acoustic work itself, though any structural alteration involved still needs to comply with the relevant Building Regulations Approved Documents. Where a new-build separating wall or floor is being constructed as part of a conversion, using a Robust Details registered construction can sometimes avoid the need for on-site pre-completion testing altogether, provided the build is executed exactly to the registered specification, though it's worth confirming with your Building Control body whether that route is available for your specific project before assuming it applies.
The most common mistakes we find in other people's soundproofing
The single most common failure is rigid fixings bridging the decoupling layer, a resilient bar screwed too tightly, or fixed directly through into the joist at both ends, defeats the entire point of the system because sound simply travels through the metal fixing instead of being absorbed. We regularly find single-layer plasterboard sold and fitted as 'soundproof board' with no resilient layer behind it at all, which adds a small amount of mass but no meaningful acoustic improvement over the original wall. Gaps left around socket boxes, pipework penetrations and the wall-ceiling-floor junction are flanking paths that let sound bypass an otherwise well-built system entirely, and acoustic sealant at these junctions is frequently skipped to save an hour's work. On floors, we've seen resilient layers fitted but then the floating floor deck nailed or screwed straight down through it into the joists below, again bridging the very isolation the material was there to provide. And we've seen ceiling systems fitted without addressing the wall-to-ceiling junction, so airborne noise happily travels around the treated ceiling via the party wall instead of through it.
Overlay treatment vs full independent construction
For airborne noise on a wall where you want a meaningful improvement without losing much room depth, a resilient bar, quilt and double-board overlay on the existing wall face, costing £700–£1,500, is usually the right first step and the least invasive option. For a stubborn noise complaint between flats, particularly impact noise through a floor, an overlay often isn't enough because the structure itself is transmitting the noise and no amount of surface treatment on one side fixes that. In that situation the more invasive option, a genuinely independent floor deck on resilient supports, or a ceiling hung on acoustic hangers below the existing joists rather than fixed to them, is usually necessary, and it costs proportionately more, £5,000–£12,000 for a full floor-and-ceiling treatment in one room, because it involves more disruption and sometimes structural input. We'll always recommend starting with the overlay where the noise type and structure suggest it will work, but we won't sell it as a fix for a problem it can't solve just because it's the cheaper option to quote.
How this differs from thermal insulation and retrofit work
Acoustic soundproofing and thermal insulation solve different problems and use overlapping but not identical materials, mineral wool acoustic quilt is chosen for its density and sound-absorbing properties rather than its thermal U-value, and a wall system built for acoustic performance isn't automatically improving your EPC rating or reducing heat loss. If your goal is reducing energy bills, addressing solid-wall heat loss, or improving an EPC rating ahead of MEES requirements for a rented property, that's a different scope covered by our <a href='/eco-retrofit-refurbishment-london'>eco retrofit and refurbishment London</a> service, and there's genuine value in planning the two together if you're stripping a wall back to the studs or joists anyway, since doing acoustic and thermal work in the same pass avoids opening the same wall twice. We'll flag where a project would benefit from combining both scopes, but we won't quote a purely acoustic job as if it were a thermal upgrade, or vice versa, because the specifications and the products that satisfy each requirement aren't interchangeable.
Leasehold, shared buildings and the Party Wall Act
Where the wall, ceiling or floor being treated is actually shared structure with a neighbouring property, most commonly the party wall between two converted flats or two adjoining terraces, the Party Wall etc. Act 1996 requires notice to be served on the affected neighbour before work that cuts into or fixes to that structure begins, and we handle that notice and any resulting party wall award as part of the job rather than leaving it for you to navigate. In leasehold flats, floor and ceiling work frequently requires freeholder or managing agent consent under the terms of the lease, particularly where floor coverings are specified in the lease to control noise transmission to the flat below, replacing carpet with engineered wood without an acoustic underlay can itself breach the lease terms regardless of how well it's fitted. HMO conversions bring their own complication, local licensing conditions sometimes specify minimum sound insulation standards between let rooms, and it's worth checking your HMO licence conditions before assuming a voluntary upgrade satisfies them.
Why the order of work matters
Soundproofing has to happen in a specific sequence or you end up undoing finished work to fix something that should have been addressed earlier. Electrical first fix, relocating sockets and switches so they sit within the new deeper wall build-up rather than being extended awkwardly afterwards, comes before any resilient bar goes up. The resilient layer and quilt are fitted and checked for continuity, no gaps, no bridging fixings, before boarding begins, because faults are far cheaper to fix before two layers of plasterboard are screwed over them. Acoustic sealant at every edge, floor, ceiling, adjoining walls, goes in during boarding, not as an afterthought once the room is decorated. On floors, the resilient layer and floating deck are completed and allowed to settle before skirting is refitted, since skirting fixed too early can itself bridge the isolation gap between floor and wall. Decoration is always the last stage, once any wet trades, plastering, jointing compound, have fully dried, because painting over damp jointing compound is a common cause of cracking that then gets blamed on the acoustic work underneath it.