Hull construction materials

[grahamnr17]

Hi Folks,

Could I ask a question about hull construction materials? I'm busy researching the kind of boat I'll end up with, and so far have settled on size (40-ish foot by 10-ish foot). Now I want to get clear in my own mind the main types of material and the pros and cons. Here's what my brain is thinking, based mostly on assumption:

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GRP/Fibreglass:

Pros: Strong, comes in all kinds of shapes, relatively easy to repair.

Cons: Cracks on heavy impact(?), osmosis, requires regular clean/anti-fowl.

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Wood:

Pros: Beautiful traditional appearance, generally built to a high standard.

Cons: Intolerant of missed maintenance intervals, water ingress/wet rot from scrapes and bashes below water line, expensive to repair.

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Steel:

Pros: Very strong.

Cons: Rust.

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Like I say, these are just my initial thoughts. I know there are some very old craft still going strong made from all these materials, and I'd welcome comments/advice/observations from those in the know and with experience of the different types.

Best regards, and thanks in advance.

Graham

[Roy]

Keep in mind I'm no expert, just my view....

but from past experience, we once had a wooden boat, before we lived on one, and I seem to remember spending nearly the whole time
we owned it, trying to keep it afloat rather than going anywhere in it.
I think they are a labour of love, needing regular maintenance, fine if
you are good at woodwork and know what you are doing, or can afford
to pay an expert to do your repair work for you.
(now let's hear from a wooden boat enthusiast to tell me I am wrong)

Steel:
Our first "live aboard boat" was made of steel. We loved her, never
worried about being hit by over enthusiastic hire boaters, she was tough.
Steel boats have a tendency to rust from the inside out, from water
in the bilge from leaky stern gland, condensation running down the
cold steel hull etc. A coulpe of times we had to have rust holes welded
over. Not a problem but found it a worry all the time.

GRP:
Our next two boats which includes our present one are GRP.
Almost maintenance free, any knocks or bashes are easily repaird
with glass or filler depending how bad.
Osmosis on a sea going boat is a cause for concern, but minor
osmosis on a river boat I have allways been told is not so serious.
(as I said I'm no expert that's what I have been told)

So personally I would always go for GRP...
Unless I had the chance of a "Steel Dutch Barge"

[grahamnr17]

Fabulous information Roy, thankyou There's no substitute for personal experience. I'm definitely going for GRP

My next bit of research shall be working out what it costs to live on a boat, and the practicalities of waste disposal etc.

[Roy]

you are welcome Graham.

[rod]

Hello...Would it be reasonable to expect a GRP broads cruiser 1970ish to last another 20 years. I am considering an ex-hire boat to liveaboard for around £20.000...low maintenance and not sinking being my only 'musts'............Thoughts Oh wise ones!....I am totally uneducated in all things Boat....it Begins here..........ROD.

[rod]

OOPS!...I doubled-up...foolish Newby....And Osmosis in a Coastal Marina...Need I fear it?...is it the...'Black-Death' of GRP?...Thoughts/Cures/Ruses/Costs?....."CHEERS!" ROD.

[billy]

Pox, the dreaded osmosis means nothing or a lot.

Most old FRP/GRP hulls are wet due to water entering the layup. This can cause the pox/blistering but it is rare that this sinks or causes significant structural problems with the vessel. It will affect the value and the potential sale and the insurers may want you to have it fixed if fully comp.

Some hulls were built badly with a dry lay up or in a damp workshops. One of my hulls had blisters and when I stripped the gelcoat off there were patches where there was no resin in the mat from new.

Diy fixes are possible, the West System has a booklet on how to deal with the pox. Yard osmosis treatment is costly, it is labour intensive and they have to guarantee the work which means they have to take out insurance.

Don't let a wet hull or the pox put you off. If you know what's going on it need not be a problem. Just bear in mind that you may not get insurance without sorting it. Third party is not usually an issue.

My little boat is GRP but my home is steel. Modern coatings (glass flake epoxy) is good for 15 years between blasting. A far cry from the yearly hull blacking of yesteryear.

Wood is lovely and I love it but I would need a man to do it for me and I can't afford that. I make do with the odd bit of pretty wood on the inside of the boats, and that is bad enough to keep up!

Glass is probably the best for an old hull. Steel is very good for new build but if an old hull has not been looked after it will need attention. It can be cost effective to rebottom a steel boat if the price is right.

A sound Ferro Cement hull is good too, a lot of folk rule them out but a good one can be great.

[Roy]

Well we have a 1977 GRP Broads cruiser, I hope, and can't see why, it won't go on another 30 years.

As long as you get it lifted every few years to check, clean, paint and antifoul the bottom.
Repairing any problems or damage, if you find any. (very low maintenance)

Billy could probably tell you more about osmosis...
But generally on the broads osmosis is not usually a problem.. (different if you intend going to sea)

Lot's of old GRP Broads boats make very good homes.

[Roy]

By the way...
Welcome to the forum Rod...

Are you thinking of living on the "Broads" or just getting a Broads boat?

[rod]

"CHEERS!" Chaps...sounds good...I am leaning towards a broads cruiser on a coastal marina...I hear residential moorings on the broads make hen's teeth seem common!?...It's open ended,I like the look of the broads I could move around...whereas I dont see me out to sea with the waves smacking me sideways ,going backwards on a strong current...Dont be fooled by my Flag...I am no Cap'n Pugwash!...So would a static coastal mooring cause the dreaded 'Sloughing Pox' to break out?..... ROD.

[Roy]

Well, You are right, there are almost no residential moorings on the broads...
BUT! there are hundreds of us on the Broads who live on our boats.
see this section on moorings to get the idea CLICK HERE


I certainly wouldn't take a Broads boat out to sea, they have been built
to cruise the rivers only, not designed to take to the sea.

[rod]

What's that boat of yours!...a 42 ft Caribbean?...I really like their 'looks'....are the single level better as a liveaboard?...Yep! TASTY..........................................R.O.D.

[Roy]

No it isn't Rod, we had a 39ft Caribbean some years back and yes it made an ideal home.

This one we are on now is a 44ft Broom (cruise master), we've got even more room on this,
I think Brooms only built two of them though.
I have seen a photo of the other one but we have never seen it on the river.

We prefer a boat all on one level for living on, seems to give you more room,
but all tastes are different.

[rod]

"YEP! ROY" I think it's looking down the long corridor...always my favourite photos in the Ads. O.K.........................................................Later ROD.