Insulating engine housing

Engine housing and cover insulation  Engine 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


  1. PU Finishing Tape
    PU Finishing Tape
    To close gaps between sheets
    • For finishing gaps between two panels
    • Oil, dirt and moisture-proof top layer, heat-resistant
    • Easy to keep clean

    Starting at £18.17

    (incl. tax)
  2. Isomat TS
    Isomat TS
    Insulations for light materials/wood
    • Mass loaded vinyl
    • Soundproofing homes, vessels
    • For flat surfaces

    Starting at £26.15

    (incl. tax)
  3. Protective top layer resist dirt, oil and moisture.
    Acousticcell PU
    Dirt-resistant absorption foam
    • Sound absorbing acoustic foam
    • Automotive, Boats, Machine Noise 
    • Self Adhesive, Protective layer

    Starting at £28.01

    (incl. tax)
  4. Flamex PU
    Flamex PU
    Dirt-resistant Absorption Panel
    • Melamine foam with PU top layer
    • Sound-absorbing, oil, moisture & dirt-resistant top layer
    • Self-adhesive

    Starting at £32.39

    (incl. tax)
  5. Merfocell PU
    Merfocell PU
    Sound absorption with a top layer
    • Oil and moisture resistant top layer
    • Sound absorption
    • Self adhesive

    Starting at £32.40

    (incl. tax)
  6. Flamex FC
    Flamex FC
    Soundproofing absorption panel
    • Fiberglass Cloth (FC) top layer
    • Heat-resistant Max. 150 degrees
    • Soundproofin for boats and vehicles

    Starting at £52.97

    (incl. tax)
  7. Merfocell FC
    Merfocell FC
    Heat Resistant absorption
    • Glass fibre cloth (FC) top layer
    • Moisture and heat-resistant
    • Applicable in engine compartments

    Starting at £57.96

    (incl. tax)
  8. Merfocom Combination
    Merfocom Combination
    Absorption and soundproofing panel
    • Soundproofing for boats & yachts
    • Sound-absorbing and Sound-insulating
    • Equipped with an oil-resistant and fire-resistant top layer

    Starting at £106.36

    (incl. tax)

Sound insulation for yacht and shipbuilding
More information about insulating yachts, ships and sloops can be found on the overview page 'Sound insulation and absorption for boat and yacht'.