Exponential Curve for Boat Maintenance Cost?

[sengland]

On my 34', I've just been through the costs of new engines, new sales, rigging, all through hulls and interior, and more so replacing those wont happen for quite a few years I hope.
Right now its all about maintenance, hauling out + antifoul and marina fees and I budget around $4500 per year for all that until I get a big ticket item in 3-4 years which could be $5k max for an engine job, and $3500 - $4500 per sail.

[Wallaby]

Originally Posted by PippaB

Come on Stu, with your units mania?

1.8, 2, and 2.2 are all exponents in your proposed equation and the whole thing describes an exponential curve A relatively shallow one maybe, but exponential nonetheless.

FINALLY!

There might be some confusion. To wit, exponential defined:

1. Containing, involving, or expressed as an exponent.
2. Expressed in terms of a designated power of e, the base of natural logarithms.

[excess_risk]

Check this active thread:

"Not Counting" costs of cruising and living on boat
https://www.cruisersforum.com/forums...d.php?t=265932

Seems the general conclusion is closer to linear at around 40’.

[Baby tug]

You can spend what you want , boat ownership can be very economical or it can be very expensive that’s obvious , I bought a motor sailor a few months back that I’m thinking of doing a refit too , I could spend 4000 or 40,000 most likely I’ll try to keep it as close to 4000 as I can , the whole reason I bought the motor sailor was to keep my fuel cost to absolute minimum , I’m basically a trawler guy , but I am looking forward to figuring out the sailing thing , sail when I can , motor when it’s more convenient , comfortable ride etc. at least I’ll be able to cross an ocean and head straight to my destinations without tacking , anyways to your point you can do it very economically, what do you really need anyways do you really need a microwave oven , holding tanks , composting heads , full suite of electronics you don’t need any of those things, Owning a boat usually cost me very little to nothing but I generally don’t keep a boat very long I’ll buy a good deal use it for a while pass it along , usually for a price that recoups my expenses I don’t know if that was helpful at all , probably not

[Phyrcooler]

Originally Posted by CaptTom

Length is only one factor. It's really complexity which increases maintenance costs. More systems and components means more maintenance. Things like dockage costs are generally based on length (or length and beam) but beyond that it's more a matter of how much "stuff" there is to maintain. And of course, your own ability to DIY.

I absolutely agree on this as well. It’s all about systems, components, and complexity - even within the same LOA. Yes, a longer boat will cost you incrementally more (think bottom maintenance and antifouling), but those other factors will have a greater impact.

And we’ve discussed it here before, but the ratio of expenses to boat value is hogwash that just keeps getting quoted as fact. Especially when some folks are talking maintenance costs, and others are including dock fees (which vary significantly from coast to coast and even within a state). My annual maintenance costs are actually significantly less for my current boat, and my dock expense is the same (same LOA)… even though the value of my current boat is almost DOUBLE the one it replaced.

[Cheechako]

Well sure complexity of the boat matters, but you would surely think a graph would be based on the same basic boat systems. It's not a projection of YOUR cost, it's a comparison! OR, the graph maker doesn't know what he's doing.

[Cheechako]

A chart of sales prices from 25 to 50 foot basic boats might just parallel maintenance actually.
All I know is it's a amazing what a fairlead block for a 50 footer costs compared with a 25 footer!

[DreaminFred]

Originally Posted by Papasail

Anybody know of any (graphs) that help show boat maintenance costs (relative to length)… all plotted out: 30’, 35’, 40’, 45’, 50’, 55’, 60’?

*wondering if something like an exponential curve has begun to fall in place as so much data has made itself clear over the years?

⛵️[emoji1360]

I suspect this is more a function of the owner and sociology than the boat and systems. If the boat is actively cruised and owner-maintained that’s going to have a given slope/function, but if the boat is professionally maintained for vacationing owners that curve is probably shifted up by 300%. Then there are the livesaboards that stay at the mooring or anchor and “maintenance” means “if it floats, it’s a 10.”

The owner also probably is the determinant on size and age. The first category above is probably 30-50’ and 15-45 yo; the second 44-120 and 20-new’; and the third is 60-40 yo.

That said I was stunned by the number of 45’ catamarans in the Bahamas this winter that were first boats of inexperienced sailor/owners. Interesting to see what happens to the used boat market in the next 5 years.

Sv Joy

[StuM]

Originally Posted by PippaB

Come on Stu, with your units mania?

1.8, 2, and 2.2 are all exponents in your proposed equation and the whole thing describes an exponential curve A relatively shallow one maybe, but exponential nonetheless.

Not at all!

> Expense = BaseCost + VariableCost * BoatLength ^2
That is not an exponentiall equation. (The exponent is a fixed value)

An exponential function is defined by the formula f(x) = ax, where the input variable x occurs as an exponent.
IOW, it's only exponential if it includes Boat Length in the exponent.

[Fore and Aft]

I don't think you can ever get an accurate curve because there's to many variables. The biggest variable would be owners attitude to maintenance.
I have surveyed so many boats where they have had zero maintenance. Just last week one boat was missing it's navigation light. The owner didn't care as he is only a day sailor. I don't think it's laziness just some people see nothing wrong with having to wiggle that cupboard door to open it or using a halyard/sheet until it breaks.
DreaminFred the cat things happened here in Australia as well. One client didn't even know that boats need antifoul paint and slipping. The delivery skipper was going to teach him everything in the two week delivery voyage. Then he was picking up the family and heading offshore.
Cheers

[Student_Driver]

Displacement is a great metric for cost. I think $1-2 per lbs per year average over ten years. Some years less. Other years more.

If i were to add a second explanatory variable it would be the boat’s disp/lwl ratio. The lower the d/l ratio the higher the cost.

So cost would look like. $1 x Disp x Max(0.75, (DLR/250)^2)

I chose 250 as a median dlr but not sure. There needs to be a floor. So i use the max function. I square that to capture the geometric cost of light stuff

Of course this is a crude approximation of the median cost across a large population of sailboats.

Generally you’ll see a Gaussian (bell shape) distribution around this number based on condition, care, usage, etc etc

[sailorboy1]

I have recorded my total living on a boat costs for 6 years and am able to determine the difference in costs for my 41' boat as it would be compared to a 30' boat. It works out to around $1500 year. That is total which includes marina costs so that is more than just maintenance costs.

For maintenance, repairs, upgrades it works out that my 41' boat costs 17% more than a 30' one would.

I will leave it for others to put together a math formula.

[Papasail]

Originally Posted by Fore and Aft

I don't think you can ever get an accurate curve because there's to many variables. The biggest variable would be owners attitude to maintenance.

I have surveyed so many boats where they have had zero maintenance. Just last week one boat was missing it's navigation light. The owner didn't care as he is only a day sailor. I don't think it's laziness just some people see nothing wrong with having to wiggle that cupboard door to open it or using a halyard/sheet until it breaks.

DreaminFred the cat things happened here in Australia as well. One client didn't even know that boats need antifoul paint and slipping. The delivery skipper was going to teach him everything in the two week delivery voyage. Then he was picking up the family and heading offshore.

Cheers

From original poster:

OMG; Yikes!; Yougottabekidding; terrifying (for putting his family on board); ya-know…. this actually doesn’t surprise me (though the horror of the thought is truly grotesque).

AND….

*I’ve seen it before. [emoji51]


A microcosm of how people think today ~
or…. don’t think.

[Papasail]

Originally Posted by Papasail

From original poster:

OMG; Yikes!; Yougottabekidding; terrifying (for putting his family on board); ya-know…. this actually doesn’t surprise me (though the horror of the thought is truly grotesque).

AND….

*I’ve seen it before. [emoji51]


A microcosm of how people think today ~
or…. don’t think.

Quick added story I was told by my father when I was about 8 years old:
“an able man bought a boat for his family, not large, maybe 20’. The main sheet got stuck in the truck at the top of the mast. He asked around a little, but mostly was told that his idea of climbing the mast to fix it wasn’t good…. that, in fact, it was a terrible idea. Put his family on board (mom, kid & newborn), presumably as ballast. Climbs the mast believing that he was safe for tying in at the edge of the dock, boat topples, everyone falls in… sail being fixed & partially hoisted, covers his family as they enter the water. Newborn dies, kid successfully resuscitated on the dock, wife divorces him in the aftermath.

[Joli]

Originally Posted by Student_Driver

Displacement is a great metric for cost. I think $1-2 per lbs per year average over ten years. Some years less. Other years more.

If i were to add a second explanatory variable it would be the boat’s disp/lwl ratio. The lower the d/l ratio the higher the cost.

So cost would look like. $1 x Disp x Max(0.75, (DLR/250)^2)

I chose 250 as a median dlr but not sure. There needs to be a floor. So i use the max function. I square that to capture the geometric cost of light stuff

Of course this is a crude approximation of the median cost across a large population of sailboats.

Generally you’ll see a Gaussian (bell shape) distribution around this number based on condition, care, usage, etc etc

I think your number of $1~2/ft per year is quite high. How are you arriving at this?