Insulation

[Nausikaa]

Hi Guys,

I'm looking for a bit of help. I am refurbishing the forecabin of my little yacht and have ripped out the old insulating mat which was glued directly onto the hull (solid GRP). I will be fixing partial frames along the inside of the hull and then lining it by attaching horizontal battons to the frames. I plan to use a lighter coloured wood for this, e.g. larch, as the cabin is quite dark, there being a lot of mahogony there already.

My question is, should I leave the space between the hull and the battons open, with say a 2mm gap between battons for ventilation or should I insulate between the supporting partial frames and, if so, what material do you recommend?

For the next few years the yacht will be in northern Europe before heading to the Med and other places where the butter melts....and stays melted!

Thanks for the help!

Stephen

Yacht NAUSIKAA

[Jack Tyler]

Hello again, Stephen...

It's an interesting question and I've done it both ways. I'd definitely opt for adding insulation with a closed-cell product.

In colder weather (and don't forget, you won't see water temps above 8-10 C until you reach Cabo Vincente, even with the warm Spanish/Portuguese summers) leaving the space unoccupied will invite hull sweating to drain downwards...which is good if the condensate makes it to the bilge, not so good if it runs out onto the V-berth platform. You will have a mold factory on the inside of the hull but the bedding & cushions won't be affected. However, insulating the hull will reduce the sweating altogether, quiet the cabin a bit (your sleeping quarters, as I recall, and also the part of the boat closest to wave slap while at anchor), and will help the cabin stay cooler in the tropics (where as you know, the sun's effects are relentless in every respect). In fact, at anchor in the tropics I'd say an ideal combination is a foredeck awning, an open hatch and an insulated hull.

In my country (USA), DIY stores offer a variety of closed cell products in 4' x 8' panels that are cheap and intended to insulate houses being built, before the exterior siding is added. Over here, I would look for foil backed (both sides) isocyanurate closed-cell foam panels, a product I used when reinsulating my icebox. I don't know if that crosses to what stores in the Baltic countries would stock, but you get the idea.

Fun project! Good luck to you.

Jack

[Nausikaa]

Hi again jack....and once more, many thanks for your time and good advice.

I am a great believer in ventilation and reached the same conclusion as you did regarding ventilating and allowing the condensate to collect in the bilge but, as you wrightly assume, that won't happen as the V-berth forms a continuous shelf from hull side to hull side. Below the berth, as tradition dictates, there is some good stowage space. I don't want to weaken the structure by building drains (which can clogg anyway) into a channel arround the side of the berth and I definately want to avoid wet bedding.

Closed cell insulation is probably the best way to go then. That being the case, I will probably insulate the deck head as well. At the moment it is covered with some kind of 'fluffy stuff' (firtunately it is only the fore cabin which has this deck head coating) which looks like very cheap immitation fur. It is very good at keeping dry though but does not provide a lot of insulation. There is a good two inches of space between the beams and the deck head so this will give me adequate space for the job withou reducing the effective headroom.

Many thanks again Jack and Season's Greetings to you.

Stephen

[panthablue]

Hi

i have a steel boat which I fitted out myself some years ago.

I had the whole of the inside sprayed with polyurethane foam. this made a one inch thick insulation which is still good today.

If you use this method, make sure you install some battons before spraying so you have something to attach the covering to.

When I did mine, I also painted the battons with cuprinol to prevent rot if they got damp.

any good to you?

[Nausikaa]

Hi Panthablue,

Many thanks for this information.

I have seen spray type insulation on steel boats and found it very good. I have not seen it used on GRP though and so I have not considered it as an alternative. Maybe I should?

Do you remember the name of the product you used?

All the best for Christmas and the New Year,

Stephen

Yacht Nausikaa

[sid]

Hi Nausikaa,

I am new to the forum and sailing, I am not sure what GRP means? I have alot of experiance with spray polyurethane foam systems though, and can give you advice on whether it could work for you. What would you be applying the spray foam too? BASF is one of the largest manufacturers, they are worldwide and can give you some info about the product.

Merry Christmas to all

Sid

Hi Sid,

GRP is glass reinforced plastic better known in Australia as fibreglass. Welcome to the discussions.

Rod

[Nausikaa]

Hi Sid,

Many thanks for your reply....and for Rod's explination of GRP.

I will be glad for any advice.

Hope y'all had a good Christmas

Stephen

yacht Nausikaa

[sid]

Hello and thanks for the welcome, now that i know what GRP is.., I hope i can give you some advice, I have sprayed polyurethane foam to the underside of many hot tubs, made of fibreglass and the adhesion was fantastic. If you decide to go with a spray foam product, remove everything you can, overspray is common and it sticks to things quite well, i.e windows and wood. The prep work is usually done by the installer, but in the case of it being your boat you may want to take the extra care in covering finished areas. The off gassing occurs when the 2 components mix and gel after approximately 6 seconds it is tack free and shortly after a finished product. Have in place before the foam is installed a means to fasten coverings..wood or whatever you will have over top. In my opinion all foam should have a barrier on it, it can be a simple paint or intermescent fire stop there are many products availible. If you have any other thoughts or questions I would be happy to answer.

take care

Sid

[Nausikaa]

<font size="3">Hi Sid,

Thanks for your last posting. The spraying of polyurethane foam looks like the 'easy option'. May well be the best one too. I will look further into this. Do you have any brand names I can check on the internet? It is always wise to find out as much as poissible before committing oneself.

Before reading your posting, I had almost decided to go for a 3M product called Thinsulate. It both insulates and isolates. 3M sell it in huge rolls so I suppose I must find a retailer who is prepared to sell by the metre if I am to go down that road.

The spray alternative does seem easier as no special adhesive will be needed. As for covering the bits and pieces surrounding the area to be sprayed, that is not a problem.

One further questipon. A friend here in Cape Town suggested using cork tiles. Any idea as to how good cork is as an insulator?

Once again, many thanks for your help Sid.

<font size="5"><font color="purple">Happy New Year ALL</font id="purple"></font id="size5">

Stephen,

Yacht Nausikaa</font id="size3">

[sid]

Hi Stephen,

I think your best spot for information for spray foam may be the BASF website, but if you google " polyurethane foam " you should find lots of information. I would assume there are a few different products available for you as far as foam systems, make sure it is a 2 pound density foam, like I said before you should put a coating on it after its applied. I do not know about cork as an insulator, I would think there is some R-rating to it, how would you adhere it to your boat, glue perhaps? I would make sure that it will be alright if it gets damp so it will not delaminate over time. Hope this helps a bit, take care

Sid

[YachtVALHALLA]

I presume everyone here has read the thread "IS YOUR BOAT A DEATH TRAP?"

[?][?][?]

Terry

[JeanneP]

Cork tiles is a bad idea, IMO. We had cork tiles on the bulkheads in the head, and the cork acted more like a sponge than anything, and rotted the bulkhead out under the cork. I don't think it has much insulating value, either.

[Nausikaa]

WOW!!!

Thanks for this. I will avoid cork like the plague then.

Incidentally, in the last YM or PBO which filtered down to the Cape there was an article about an ex RN guy and his 'Kingfisher'. The Kingfisher had cork tiles on the sole and bulkhead. It seemed ok but he was just summer sailing in NW Europe.

Anyway, thanks for the advice. Cork is out!

Stephen

yacht Nausikaa

[Nausikaa]

Just wanted to let you alll know that I have found a closed cell foam product manufactured in the UK called Versifoam which is a closed cell, sprayable Polurethane Foam that comes in an easy to use kit

It is supplied in two sizes of kit:

Versifoam 15 is very portable and you can get into small spaces. It yields about 0.34m3 of Foam per litre.

Versifoam 50, although portable yields about 1.0m3 of Foam and gives cost advantages over the 15's.

This should do the trick! I'll let you know how I get on, costs and how easy it is to work with later on.

All the best

Stephen

yacht Nausikaa

[brightspell]

I've also previously used cork tiles on my grp sailing cruiser, but found that they became discoloured and more alarmingly, tended to curl out at the corners. After a while they would lose all remaining adhesion.

Therefore, I will try out the Versifoam product. I've been kipping out on the boat on a deep `trot' mooring in mid December (minus cork tiles) and found that its a bit `taters' especially with a 5 knot spring tide running in the Swale!

Regards BS

www.moreinfo247.com/8821255/free

[Oscar]

Originally Posted by name='Converted Post'

GRP is glass reinforced plastic

Actually, to be completely correct it's "Glass reinforced polyester."

I am sure they are illegal in many places outside the US as well now, but be advised that some spray on foam insulations in the past have contained formaldehyde, and are considered a health hazard. I'm sure any modern 3M product is up to date in that respect.

[Nausikaa]

Thanks for the warning Oscar. It is difficult to know what is good for you and what isn't these days.

I am working in Yeman at the moment but I keep my boat in Denmark and I am fairly sure Denmark is clued up on banning chemicals which are considered a health hazard. I intend to do the work when IO hav eleave next month so I will see what is available.

Cheers,

Stephen

Yacht NAUSIKAA

[Chetan]

hi all

many of the options discussed seem like "non-options" after reading the "IS your death a boat trap" thread.... or am i missing something?

glad for any clarification or input

cheers