sound proofing

[Chalky White]

Hi to all you fellow boaters, well that old question of sound proofing has come up yet again well I am looking into getting my boat sound proofed carry out a few test and put my finding on here along with a supplier so if you thinking of doing it watch this space

 

Chalky White

[p6rob]

I'll be very interested in the results.

At the moment I'm thinking of replacing my solid engine mounts for rubber and making an acoustic housing for the engine, or lining the engine 'ole with sound proofing sheets. I guess the engine will run hotter if it's enclosed but, with the engine in the way, it's going to be difficult to do a decent job of lining the engine 'ole.

 

Yesterday morning (6:30) as I walked along the tow path one of the moored boats had his engine running. It wasn't until I was halfway along his boat that I became aware the engine was running, however I got about two boat lengths past the rear of the boat before I could no longer hear it. To be fair though, it was moored by the A5 road bridge, so even at that hour there was a lot of ambient noise to mask it.

Unfortunately they'd moved on by the time I got back from work, so didn't get chance to ask about their sound insulation.

 

Rob

[musicman]

Quite a number of years ago now I made a generous box to encase the engine and lined it with foil-backed soundproof sheets. The sheets had a heavy membrane as part of their construction. It wasn't cheap, but the difference was incredible. I found that at the tiller, what had been a noisy boat was now much, much quieter. Long cruising sessions were a much better experience as a result. The exhaust on my boat is still fitted with a normal silencer - I guess the next step to an even quieter engine would be to fit a hospital silencer.

[Robbo]

Hi to all you fellow boaters, well that old question of sound proofing has come up yet again well I am looking into getting my boat sound proofed carry out a few test and put my finding on here along with a supplier so if you thinking of doing it watch this space

 

Chalky White

 

Presume you mean sound insulation , and in the engine room. I think the best solution instead of going for the pre-made foam-lead-foam solution is too form these same layers. You can then use denser foam and thicker "lead", but mainly because you can overlap the layers.

 

Also remember to quieten a engine, the insulation is only half the job.

Edited June 11, 2014 by Robbo

[jake_crew]

Weight is good, but lining the engine 'ole with paving slabs isn't realistic.

 

Stopping large panels from booming is good - so the stick on sheets as above can help, thou they're often intended for cars hence they will work better on thin (1mm thick) metal.

 

In a previous life I worked on sound/vibration proofing aircraft parts where lack-of-weight is a major requirement.

 

For large panels, another panel can be loosely riveted to the first so that the two can "clap" together. Soft aluminium works well for this as it has high damping chacteristics. If using the same material for the second panel, make it a different thickness.

[Robbo]

Weight is good, but lining the engine 'ole with paving slabs isn't realistic.

 

Stopping large panels from booming is good - so the stick on sheets as above can help, thou they're often intended for cars hence they will work better on thin (1mm thick) metal.

 

In a previous life I worked on sound/vibration proofing aircraft parts where lack-of-weight is a major requirement.

 

For large panels, another panel can be loosely riveted to the first so that the two can "clap" together. Soft aluminium works well for this as it has high damping chacteristics. If using the same material for the second panel, make it a different thickness.

 

For canal boats weight isn't really be an issue. So using dense heavy material is better.

Edited June 11, 2014 by Robbo

[John V]

My yoghurt pot is very quiet, the engine sits in a case in the centre of the boat. the top and sides of which are lined with foam/lead/foam soundproofing sheet. Although far from silent on board, due to its position under the galley sink, from the canal bank it is very, very quiet. The water cooled exhaust helps a lot as well.

IMO composite soundproofing material is the way to go (but expensive).

[Machpoint005]

The OP doesn't say what type of boat he is playing with.

If it's a cruiser stern or semi trad narrow boat, the first thing to do is make sure the deck boards fit snugly.

[Neil2]

Despite the fact that most NB engines are flexibly mounted these days, a lot of the vibrations from the engine are still transmitted to the hull through the transmission. I reckon this is the noise that most people find intrusive. If you create a flexible coupling and allow the engine mounts to do their job all you have to deal with then is the actual noise of a diesel engine, which in many cases isn't actually that bad, and the exhaust note.

[Paul's Nulife4-2]

I found that this -

https://www.dropbox.com/sc/fcy9u7aw122ezts/AAAk6m-fUBD3e9HbZi3n8qvOa

Coupling, Dramatically reduced Noise /Vibration.

[Hairy Animal]

I've recently put a very noisy diesel generator into a cocoon to make it usable on board our boat, and used a multi-layer barrier mat from Bicester Soundproofing Products (http://www.bicpro.co.uk/soundproofing-materials.htm). They're very helpful and if phoned are happy to discuss any particular problem and advise which of their wide range of products is the most suitable. I'm very pleased with the mat I bought from them, though it was expensive.

[Neil2]

I've recently put a very noisy diesel generator into a cocoon to make it usable on board our boat, and used a multi-layer barrier mat from Bicester Soundproofing Products (http://www.bicpro.co.uk/soundproofing-materials.htm). They're very helpful and if phoned are happy to discuss any particular problem and advise which of their wide range of products is the most suitable. I'm very pleased with the mat I bought from them, though it was expensive.

The heavy soundproofing mat looks interesting - it's not boat related but I'm looking to improve the soundproofing of one of our rooms at home - could you give us an idea of cost?

[Robbo]

 

The heavy soundproofing mat looks interesting - it's not boat related but I'm looking to improve the soundproofing of one of our rooms at home - could you give us an idea of cost?

Sit down first, if it's a reasonable size room you'll be looking at around £1000-2000 to do it right. Edited June 11, 2014 by Robbo

[Neil2]

Sit down first, if it's a reasonable size room you'll be looking at around £1000-2000 to do it right.

Maybe I'll use Axminster instead, sounds like that would be cheaper.

[Mike Jordan]

There is due to be an article in the next edition of WW which shows a very effective method of reducing the noise levels for minimum cost.

Musicman - Before you splash out a hospital silencer, see if you can find anyone who has achieved a good result with one. Ive found them to be of little use, its not the exhaust note that makes the clatter but the engine in a tin box.

[Paul's Nulife4-2]

Hi all,

Can I just ask what peoples definition of a Hospital Silencer is, I ask as i don't know if this is another name for something like A Water Lock silencer which is what I use on both my Main Engine & my Generator, that's all.

If so I can honestly say it makes a HUGH difference in the antisocial noise of exhaust made.

[Mike Jordan]

As I understand it the name came from the type of very large and expensive silencers used to cut the exhaust noise from hospital emergency generators. the amount of power required to allow a hospital to continue to function during a power failure means a massive automatic starting diesel. The silencers are very good at keepimg the noise level to acceptable limits. I assume that the water traps are in a wet exhaust system, as you say a very efficient silencing method but not one in general use in narrowboats these days.

[capri sun]

I was wondering of using some "Celotex" as sound proofing in the engine bay as I have been offered a load

my worry is is it suitable on a cruiser stem NB if I stick to the the outside metal re fire hazard

Roger

[Paul's Nulife4-2]

As I understand it the name came from the type of very large and expensive silencers used to cut the exhaust noise from hospital emergency generators. the amount of power required to allow a hospital to continue to function during a power failure means a massive automatic starting diesel. The silencers are very good at keepimg the noise level to acceptable limits. I assume that the water traps are in a wet exhaust system, as you say a very efficient silencing method but not one in general use in narrowboats these days.

Ahh, yep got ya.

Cheers.

[Alan Saunders]

Looking under the bonnet of diesel-engined cars, they have absorbent, dense foam shields on the top of the engine. Certainly, removing this clip-on shield from my 2002 Clio noticeably increases the noise level. Maybe the engine bulkhead has additional sound insulation; the diesel clatter is more noticeable with a window open but nothing like the noise from my Vetus M3.10 under an 18mm ply deck.

 

Short of the expense of a full engine cocoon a moulded engine cover and engine/bulkhead insulation may obtain acceptable noise levels to the steerer and the cabin occupants.

 

HTH, Alan

[Robbo]

I was wondering of using some "Celotex" as sound proofing in the engine bay as I have been offered a load

my worry is is it suitable on a cruiser stem NB if I stick to the the outside metal re fire hazard

Roger

I think Celotex is closed cell, it will be useless for sound insulation.

[Paul's Nulife4-2]

I was wondering of using some "Celotex" as sound proofing in the engine bay as I have been offered a load

my worry is is it suitable on a cruiser stem NB if I stick to the the outside metal re fire hazard

Roger

Hi ya,

You will have to confirm, but I think Celotex FP 500 or something like that is the fire proof one. And is definitely a cheaper option but,,

It's designed more for Temperature insulation, than sound insulation, if that makes sence.

 

I think.

Edited June 11, 2014 by Paul's Nulife4-2

[ditchcrawler]

For information on Quietlife see the link below

 

http://www.asap-supplies.com/marine/boat-soundproofing-and-noise-insulation

[Beaker]

For information on Quietlife see the link below

 

http://www.asap-supplies.com/marine/boat-soundproofing-and-noise-insulation

 

That link is broken, try this:

 

http://www.asap-supplies.com/marine/boat-soundproofing-and-noise-insulation

[ditchcrawler]

 

That link is broken, try this:

 

http://www.asap-supplies.com/marine/boat-soundproofing-and-noise-insulation

Sorry and thanks for the fix