General Requirements
When undertaking testing to determine compliance with Part E of the Building Regulations it is important to ensure that the tester is a suitably qualified and competent person in the measurement of sound insulation in buildings.
Testing is required for new dwellings that adjoin other buildings and works involving the material change of use of a building that will become used as one or more dwellings.
Testing should be completed only when the dwellings either side of a separating element are complete with the exception of decoration. Testing is not required for all dwellings; a portion of the dwellings= should be reflective of all different construction methods used throughout a development.
Sound insulation testing should be undertaken between rooms or spaces that are separated by a common separating wall or floor.
Soft furnishings should not be installed prior to the completion of impact sound insulation testing. Where a resilient material is to be used on the surface of the floor it must be bonded in place prior to testing.
Testing for sound insulation is not required between common circulation routes and dwelling spaces as the results may be unreliable however, compliance can be demonstrated by inference i.e. using similar construction should to achieve the appropriate level of sound insulation in other areas.
While testing of all separating walls and floors is not required the methods of construction used should be consistent throughout to ensure the appropriate levels of sound insulation are achieved. Should construction methods change additional testing will be required to demonstrate compliance for all methods of construction.
Amount of Testing Required
While a set of tests relates only to the particular dwelling tested it can be said to be indicative of the performance of that construction type. It is important to ensure that dwellings are grouped together based on their construction type and the appropriate amount of test are completed for that group.
Dwellings are categorised into two types – dwellings house which include bungalows and apartment/duplex dwelling houses. Dwellings should be grouped based on their type and the type of construction used. For dwelling houses the groupings should be formed based on the separating wall construction between dwellings. For apartments/duplex buildings the groupings should be formed based on the separating wall and/or floor construction. Where room sizes are generally the same and the construction methods and associated flanking construction, details remain the same throughout sub groups may not be required.
Sets of Tests
Table 2 of Technical Guidance Document E provides details on the number of tests that should a ‘set of tests’ should comprise to ensure an accurate result is obtained. This table, which has been provided below for clarity also indicates the type of test that is required in a particular location.
Table HE2 - Number of individual tests in a 'set of tests' - Extract from TGD E
Programme of testing
Initial Testing
At least one ‘set of tests’ should be completed on a dwelling group or sub group within the first four dwellings to be brought to completion, this is applicable regardless of the size of the group or sub group.
Minimum Frequency of Testing
Where all initial tests have passed the frequency of testing per group or sub group should comply with the requirements of Table 3A of Technical Guidance Document E which has been provided below for clarity. The testing frequency as outlined in Table 3A below is only application if construction is in accordance with Sections 3 and 4 of this document.
Testing should be completed more frequently at the beginning of construction to ensure any issues are addressed at an early stage.
Table HE3A - Minimum frequency of testing per group or sub-group - Extract from TGD E
Reporting Procedure
Appendix A of Technical Guidance Document E, details the appropriate method for recording the test results, these results should be retained as proof that the requirements for sound insulation performance have been met.
Failed Tests
Should an individual test relating to airborne or impact sound insulation not meet the minimum requirements detailed in Table 1 of Technical Guidance Document E then that ‘set of tests’ is deemed to have failed.
Should a test fail remedial works should be undertaken to ensure that the element meets the requirements detailed in Table 1 of Technical Guidance Document E, this is determined by ways of a retest. Should the retest fail additional remedial works should be carried out until such time as the minimum requirements. If there are other dwellings of the same construction type already completed on this site prior to the failed test(s) then similar remedial works should be completed on these dwellings also.
Should remedial works be required the number of sets of tests required should be increased by one for that group or sub group.
Where the failure relates to the construction of the separating element and/or the associated flanking provisions all other separating elements of similar construction should undergo remedial works to ensure the performance requirements detailed in Table 1 below are met.
Table HE1 - Sound performance levels - Extract from TGD E
Assessed Sound Details (ASDs)
Where the methods of construction are not in accordance with Sections 3 and 4 of this document certified construction details should be used. Appendix B of Technical Guidance Document E provides details of certified construction types, if these details are adhered to the testing frequency is to be in accordance with Table 3A of Technical Guidance Document E.
Table HE3A - Minimum frequency of testing per group or sub-group - Extract from TGD E
Other Constructions
If construction is not in accordance with the assessed sound details, provided in Appendix B of Technical Guidance Document E or the construction details provided in Section 3 and 4 of this document then it is essential that the frequency of testing is increased to ensure the proposed detail is capable of meeting the required performance.
A ‘set of tests’ should be completed on every dwelling within a group or sub-group within the first eight dwellings which are to be completed on that site.
Where none of the above tests have failed the minimum number of ‘sets of tests’ should be in accordance with Table 3B of Technical Guidance Document E.
Table HE3B - Other constructions - minimum frequency of testing per group or sub-group - Extract from TGD E
