How to insulate the engine housing or engine cover

Engine housing and cover insulation
Many pleasure crafts have an onboard engine housing or engine cover that is part of the deck of the boat, mostly sloops and smaller vessels. The engine housing, or cover, is usually made of fairly light materials such as wood or polyester. These light materials are the main reason for noise problems on those crafts. We have the solution and products to solve this issue and make your boat ride more pleasurable.
An important thing to keep in mind: make sure to use a product with sufficient heat resistance!

How to insulate the engine housing or engine cover
To insulate engine noise you need to install an acoustic noise absorbent product in the engine housing or cover, as thick as possible. Make sure that the whole engine housing or engine cover is insulated, do not skip parts, this will result in noise leaks! Products cannot touch parts of the engine. The picture on this page shows an excellent example of an engine cover insulated with Merfocell PU and taped of seams.

Products to insulate the engine cover and housing
When you have less than 10 cm between the engine and a product we speak of high temperatures. These products are the ones we recommend:

Merfocell FC: Max. 110 °C. Fiberglass cloth top layer.
Flamex FC: Max. 150 °C. Fiberglass cloth top layer, for flat surfaces only.

If the engine room or engine compartment is larger, with at least 12 cm or more distance between the engine and the absorption material, we can assume that temperatures are medium and not higher than about 60 to 70 °C. It is your responsibility to make sure if this is true. These products are the ones we recommend:

Acousticcell PU:, Max. ± 80 °C, PU protective top layer oil- and moisture proof.
Merfocell PU: Max. ± 80 °C. PU protective top layer oil- and moisture proof.
Flamex PU: Max. ± 100 °C. PU protective top layer oil- and moisture proof.

How to isolate engine noise
To reduce low engine noise even more, from big diesel engine for example, means to isolate the engine. This is done by making the engine cover, hatch or housing, as heavy as possible. Only with mass you can isolate the lowest frequencies. You can achieve this by installing heavy Isomat TS sheets on the engine housing or engine cover and then apply an acoustic noise absorbent product as described in the paragraph above. These are the recommended products:

Isomat TS:, Max. ± 80 °C, Mass load vinyl to increase mass and insulation
Merfocom: Max ± 100 °C, Soundproofing and absorption.

Products for insulating the engine housing, engine cover

Insulating engine housing