Essentially, for part floors you need to carry out two types of sound insulation test which is airborne sound testing and impact sound testing. The airborne sound insulation test is carried out by means of a loudspeaker emitting a steady source of noise on one side of the partition (wall or floor) to be measured.
The two types of tests are as follows:
Airborne Sound Tests – These tests are carried out to the floors/ceilings between dwellings. An airborne test measures levels of sound transmitted through the air. We use a loudspeaker that produces white noise on one side of the partition, and measure with a decibel meter on the other side how much sound is lost through the partition. Airborne noise is usually associated with televisions, radios and people talking.
Impact Sound Tests – These are only carried out on separating floor/ceiling divides between dwellings. An impact test measures the levels of noise transmitted directly through a separating construction as a result of impact. We use a tapping machine, which drops metal hammers onto the floor to create impact noise. We then measure the amount of sound that passes through the partition with a decibel meter on the other side of the divide.
Sound testing should be carried out on ‘habitable’ rooms. Habitable rooms can be bedrooms, lounges, living rooms and open plan kitchen/ living spaces.
Preparing for Sound Testing Floors in Flats
1. The whole building envelope and internal walls and floors should be fully completed
2. All electrical fittings must be completely in-place, and fully functional. Poor electrical installation can lead to excess noise.
3. 240 volt power should be in-place and available in every room. Our testing equipment can be damaged by the voltage fluctuations of on-site power generators, so it’s essential to have 240V mains supply on-site on the day of the test
4. No carpets or laminated flooring should be fitted on the 1st floor levels or above. These materials can affect the movement of noise, and as a result could impact on whether a building passes the sound check test.
5. The building skirting should not touch the floating floor.
6. All gaps in the walls and floors should be sealed. Again, noise can leak out through any gaps, affecting the movement of sound and impacting on the space’s performance.
7. Access to all of the rooms on all levels should be granted to our technicians, with all noise sources (radios, alarms, building work) ceasing for the duration of the test.
8. The above points are all essential if we are to achieve accurate sound test readings. If any of them are ignored, there is a risk of you either failing your test or – at worst – not being able to complete it, at which point you may still be charged 75% of the test fee.
Acoustic Floor upgrade for passing sound testing on Existing Flats
To reduce airborne and impact sound transmission this usually means adding density and isolation to the floor construction. This can be as simple as adding a drop ceiling consisting of 125mm timber frame. The top of the frame must be a minimum of 25mm below the existing ceiling finish – such as lathe and plaster. Then, to the inside of the timber frame add 100mm of Acoustic Wool and two layers of sound-board tacked to the bottom of the timber frame – all boards to be lapped. This should improve your sound test results by approx. 15dB depending on the existing site conditions and quality of the installation.
The main design considerations for sound testing floors in Flats
To improve the chance of a successful sound test and reduce the chance of noise flanking you will need to ensure that you allow for the following five acoustic design considerations, when upgrading an existing floors and walls in flats they are:
Reasons for sound testing floor failures in Flats
- Shared Structural Building Components – Floor Boards, Floor Joists, Continuous Drywall Partitions, Continuous Concrete Floors, and Cement Block Walls.
- Through Structural Steel (structural steel beams are often a major cause of noise transmission as plasterboard is often fixed directly to the steel without sound breaks)
- Plumbing Chases – Junctures between the Walls & Floor Slab Above or at the Exterior Wall Juncture (this should be filed with mortar etc. to add mass to this weakened areas.
- Through Windows (if they are no double glazed or have secondary glazing as a minimum)
- Fixtures & Outlets – Light Switches, Telephone Outlets, and Recessed Lighting Fixtures (if penetrations have been cut back to back with the opposite dwelling under test)
- Structural Joints – Perimeter Joints at Wall & Floor, Through Wall & Ceiling Junctures (these should be filled with acoustic mastic.
- Around the End of the Partition Through the Adjacent Wall (acoustic mastic should be used to seal this junction)
We can advise on all types of acoustic design to help you pass your sound testing to walls in flats, whether it’s accomplished during initial construction or during a refurbishment/renovation project. We also undertake UKAS accredited sound testing providing a ‘one stop’ solution for all your acoustic requirements.
If you would like more information in regards to sound testing please follow our blog or contact us at firstname.lastname@example.org or call Darren Direct on 07775623464. Alternately, if you would like more information on how to prepare for your sound testing please download our sound test checklist.