DIY projects may offer self-satisfaction, but are you saving much? The problems created by an amateur can cost plenty in the long run.

It’s a recurring question, installer Len Wallis says, when asked why consumers should engage a professional for their AV installations rather than doing it themselves.

“The average client does not have, and should not be expected to have, the knowledge to correctly design a whole-of-house system.”

Len Wallis is somewhat of an industry stalwart. His Sydney-based store, Len Wallis Audio, celebrated its 30th anniversary in July.

He says his company is spending more on staff education than ever before.

“Technology is moving at an alarming rate, and the knowledge needed to integrate all the components is growing at an even faster rate.

“And then there are the lessons learnt in the field. Through bitter experience we know which Marantz DVD players will not work with which Fujitsu plasmas via HDMI, or which routers are incompatible with Sonos systems.

“Even when customers try to cut corners and use their sparky, it comes unstuck in many cases.”

To emphasise the importance of using a qualified professional, Len has the following procedures in place for all projects.

Before sales staff can quote on a job, they must arrange for a site inspection by a project manager, who forwards a report to the sales person.

Next, the sales person does the system design, which must be checked and signed off by the project manager before it goes to the client.

“Once accepted by the client, the project must go to our draftsman, who prepares a cabling overview ­– what cables need to go to which rooms, and so on ­– and a wiring schematic that shows the exact positioning of every interconnect and cable, thus ensuring that nothing has been missed.

“The frightening thing is that on occasion we still get it wrong.”

Reliability is an important element of AV installations, Len says.

“We aren’t dealing with two or three-piece component installations any more. Most systems are made up of 10 to 20 components.

“If some of these components are unreliable, you are going to spend a fair amount of time with the system out of action.”

Len says there’s a place for ‘theatre in a box’ solutions for people who are looking for a basic home theatre.

“However, if performance is a priority you cannot go past a correctly designed system. This requires a little more work, and possibly a good deal of faith in an installer, but the results are well worth it.”

Len says the problems caused by DIY first-timers can be expensive and time consuming to rectify.

“The most common mistake is not running cables to allow for control of speakers in rooms. We regularly see jobs where cables have been run for speakers into different rooms, but no allowance has been made for any control system in these areas.

“It is also common for us to be brought in on a job where the design and cabling has been a DIY project, only to find that the cabling is wrong and, as the walls have been closed, it is too late to do anything.”

Another mistake is screen size – most customers are still looking for screens that are far too large for their rooms.

“A screen should not represent any more than half the cost of the system. Enjoyment from a home theatre system is made up of vision and sound, and equal emphasis should be given to both.

“But the thing that really frustrates me is that people assume we can teach them, or their contractors, everything that they should know in the space of a few hours.

“We spend about $50,000 and many, many hours a year on training and still don’t know it all.”

Len says the most damage is caused by people attempting to install a system, such as the Bunnings-stocked Winplus sytems, that shouldn’t be installed in the particular environment.

“Rectification can be costly and messy. In some cases it means chasing into walls, which then need to be repatched and repainted.

“The worst example of this was a project we were involved in where the clients wanted automation but had the home wired in the conventional daisy chain fashion.

“Although we were able to automate the home, we had to completely rewire the house, which meant removal of the ceilings in most of the rooms.

“In most cases the cost of rectification is more than the saving made by going it alone, and far greater than it would have been to have a professional do it in the first place.”