Sound insulation testing: passed, handed over.

Approved Document E requires at least one set of tests for every ten dwellings in each group or sub-group of constructions, roughly a 10% sample. For houses, a set is normally two airborne wall tests; for flats it can be up to six tests, covering airborne wall, airborne floor and impact floor performance in pairs. Send us your plot schedule and construction types and we'll confirm the exact count. No over-testing.

For new-build dwellings, separating walls and floors must achieve at least 45 dB DnT,w + Ctr airborne, and separating floors no more than 62 dB L'nT,w impact. For conversions (a material change of use), the standards are 43 dB airborne and 64 dB impact. Higher targets can apply where a planning condition or BREEAM sets them.

Near completion but before handover, and crucially before carpets go down. The rooms either side of the element need to be complete: doors and windows fitted and closable, sockets and switches in, ventilators fitted, and bare floors where impact tests are due. Testing too early risks a fail that the finished building would have passed; we'll run through readiness with your site manager when we book.

You get a clear diagnosis of the likely cause (flanking paths, missing or bridged isolation, gaps and penetrations are the usual suspects) and practical remedial advice targeted at it. Once the fix is in, we retest the element. Building control needs the pass, so the sooner a failure is found and fixed, the less it disrupts handover.

Every project is a fixed fee agreed up front, so we don't publish a price list. Send a postcode, the number of plots and the construction type and we'll come straight back with a figure. No day rates, no surprises.

Most jobs are a single site visit, and we offer flexible scheduling including short-notice slots. Tell us your handover date and we'll work to it. Certificates suitable for building control land within five working days of the test.

The rooms need to be finished and quiet: mains power live, windows and external doors fitted and closable, internal doors hung, trickle vents installed, sockets and light fittings fitted, and no trades working in the test areas during the visit. We send a short readiness checklist when the test is booked. Sites that follow it pass the visit off in one go.

Airborne testing measures how much sound a wall or floor blocks: a loudspeaker one side, measurement the other. Impact testing measures footfall through floors using a standard tapping machine. Separating walls need airborne tests only; separating floors need both. Approved Document E sets the pass values for each.