Question
We are bothered by noise from a neighbor's gas-fired pool heater exhaust vents which point in our direction. The slope of the properties prevents any mitigation measures on our end, but our neighbor is willing to have us address the noise on his property at the source. The gas company troubleshooter said we should address the problem through landscaping. What would you recommend we do?

Answer
Hello,

I would suggest some type of acoustic wall and/or an insulated enclosure for the heater.Walls can be constructed of concrete,masonry or wood. The most effective would be concrete filled with solid foam insulation. Locate the wall as close to the noise source as possible.

A concrete wall would consist of a series of horizontal concrete boards layed into slots in concrete posts,the space between the outside and inside concrete boards being filled with solid foam insulation. The structure must continue to the ground since noise will get through any gaps at ground level.

An ordinary concrete block,stone or brick wall will also have some sound deadening effect. A concrete block wall filled with solid foam in the openings in the individual blocks would be much more effective.

The comparitively least effective sound barrier would be a wooden timber fence. This type of fence consists of heavy timbers layed horizontally between timber supports. An ordinary wooden fence would not be very effective since it is too thin and sound would transmit through any gaps in the fence.

Another type of wooden fence could be made of exterior plywood panels with solid foam insulation sandwiched between. An exterior plywood fence may have a shorter lifespan than other wood fence types. The plywood must be kept coated.

It is important to seal the tops of all foam filled fences to keep water out. Build the fence as high and as long as possible. Most likely the fence will have to be constructed over the legal fence height for your area and you may need to apply for a variance from your zoning board.

You might also want to consider an acoustic enclosure for the heater. This is an insulated box that would surround the heater. This option would be alot cheaper than a concrete fence but I cannot tell you how effective it would be.

Noise also may be coming from moving parts in the heater and/or expansion and contraction from heat and cooling. Perhaps the heater can be noise isolated,rubber boots,pads,etc..applied to the heater to stop noise from vibrations. Some noise may be coming from vibrations that transmit through the ground and air and reverberate off building surfaces. Since you are downslope,perhaps some noise is reverberating inside the area created by the slope.

Manufacturers of this type of equipment often do not make a serious effort at sound engineering even though such engineering can often be done at comparitively low cost. Perhaps the heater could be replaced with a quieter model. Good luck. Let me know if I can be of further help.

Mark Harshman
http://www.mahdrafting.com
Email: [email protected]

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