End-users, construction companies, developers, architects and acoustic consultants are increasingly bombarded with information from companies who either manufacture and sell or simply sell products for sound insulation and sound absorption. Yet the information coming out of these companies and the technical advice and support provided by them can be highly variable.

Why should it be like this? What do user groups require of the supplier companies? This shouldn’t be a difficult question to answer. Despite there being specific differences in their needs there are a number of common elements.

All are looking for quality products, proven solutions and correct technical advice. Yet, what are the messages coming back from the recipients of this information? The main complaint from end-users is that of receiving technical information that creates confusion, leading to decision making being a real problem.

There are many different methods and ways of expressing sound insulation performance and it is all too easy to confuse the layman, who may not have appreciated the difference between airborne and impact sound, yet alone, the difference between laboratory and site test results. Increasingly one hears of “fairy-dust” solutions being offered with guarantees of peace and quiet that simply cannot be achieved.

One recent caller to our offices, Paul Hanrahan, site manager for CK Properties, complained of just this problem. Paul commented that “I’ve recently been talking to another welladvertised sound insulation material supplier, who provided me with a solution to a particular acoustic problem we faced on a current project. They advised that their particular product would guarantee compliance with Part “E” of the Building Regulations and provided trade literature purporting to support this, as well as providing a sample. Believing this, we purchased and installed the product only to get a significant failure when tested.

Subsequently, on taking our now larger problem to Floorscan Acoustics, a distributor of SRS products, we were given much more information and made aware that the performance of these materials will differ from site to site, since they only form a part of the total floor or wall construction. Not only that, we were advised by Floorscan that the SRS product, of which the other product was a clone, would not meet Part E in this particular situation. An alternative SRS product was offered, and shown to provide compliance on site prior to purchasing the total metreage required.

It’s been a costly exercise, but we certainly know who to go to next time, and why.”

At the other end of the spectrum, of necessity, acoustic consultants are required to keep up-to-date with the latest developments in acoustic systems and products. The number of providers is now large with many new manufacturers and/or suppliers having appeared in the marketplace over the last few years. Not all employ experienced, qualified personnel with a knowledge of building acoustics and/or site experience. As a consequence, on many occasions, these consultants find that they are faced with difficulties in ensuring proven products are used on sites. Erosion of specifications becomes all too common.

Duncan Templeton, of leading practice, BDP Acoustics, commented that: “We rely on the architect and engineer incorporating in design drawings and contract documents, acoustic requirements which we define carefully and scientifically, based on laboratory and field test data. Too often this advice becomes generic rather than specific, when it comes to product selection.

The architect has to balance acoustic performance with other parameters – appearance, buildability, durability, fire rating and fixing. The contractor is swayed by cost, availability via supply chain partners and ease of site assembly. The result is compromised product selection and installation.”

A further example has come to our attention only this week that reinforces the problems outlined above. SRS’s Acoustilay had been used successfully on a flat conversion in one street in Lancashire. The product had been specified following a diagnostic site survey. The good news spread and a near neighbour wanted to follow suit. This time the site survey revealed that a more rigorous solution was required and a ceiling treatment was recommended in addition to the application of Acoustilay.

Yet, what did the client and contractor do? Seeing that Acoustilay had worked further up the street they decided to omit the ceiling treatment and just go for the acoustic underlay; not Acoustilay, but a cheaper clone. The result was a failure with the end result being increased costs for the necessary remedial action.

What can the specifier and end-user of the information do to remedy this situation? One thing is certain; there is no one correct route to success.

As illustrated above, just as every construction site is different, and that difference may result in a different acoustic performance from the identical product/system when used in it, there is no simple panacea. However, there are some simple guidelines that should be adhered to; so that the recipient of the information can be assured that they are receiving the appropriate recommendations and the appropriate product(s) for their particular noise problem.

What we are all seeking is confidence in the choice of the right material/system for use in the right place and key to gaining that confidence is that the advice, recommendations and ongoing support is coming from the right people and is followed without specification erosion.

Helpful Tips

• Use proven products and/or solutions

• Longevity of product indicates that it has a proven success rate. Look-alikes and clones may not have been subject to the same level of testing and will not have the same track record. Testing can be costly and some companies may not wish to incur these costs, gambling on similarities to proven well-established products and a lower price securing them the business. The holding of a patent for the product or seeing a registered trademark on the product can act as a good indicator.

• Longevity of a supply company indicates that they are likely to have a proven track record.

• Ensure that a supply company has appropriately qualified technical personnel e.g. members of the Institute of Acoustics. New companies on the block are not precluded from this and may meet these criteria, but you should check this out, as graduate level qualification alongside practical experience and the support of appropriate IOA member referees are required for consideration for full IOA membership.

• When looking at companies claims for products/systems, ensure that you compare “apples” with “apples” e.g. DnTw with DnTw (site recorded data under real conditions) and not Rw (laboratory recorded data under perfect conditions). Rw figures will look significantly better than the DnTw figures measured on site.

• If in doubt, ask for an acoustic condition survey to be carried out. Knowing the starting point makes recommendation of the appropriate solution simpler, with much greater guarantees of success.

• In the current age of increased sustainability and protection of the environment, a traceable audit trail is important. Ensure that your supplier can provide this for its product range.

• If still in doubt, simply ask!!! Reputable companies will certainly be willing to provide you with relevant information regarding the company, its personnel, as well as copies of laboratory and site test data.

Comments