Architectural student still has boat house design question !

Architectural student still has boat house design question !

Post by Mathew Pee » Thu, 20 Jan 2005 07:05:45


Flooded boat houses in Cambridge flooding 2001:
http://www.firstandthird.org/tables/information/floodsmich01p2.shtml

What happened inside one of the boat houses:
Severe flooding swept through Cambridge, and our boat bays found
themselves under a foot and a half of water. Unfortunately, Peter Brandt's
airtight construction meant that it floated in to the underside of the
rack above - severely cracking the shell, taking the club's new novice
boat out of action for the second novice term in a row.

Seems like having racks without sharp edges would generally be a good
idea... and do any of those houses in Holland ever raise and then float
away in a flood??

Mathew

On

Quote:
> Due to proximity of water flooding is potentially a problem in many
> locations.
> Personally Im looking at designing/building a boat house or picking up
> someone elses design and building.

> The systems Im particularly interested in are:-

> Systems to automatically raise racks as flood water ingresses.
> OR to raise the whole building as water levels rise.

> In holland they have houses built with this type of system so not
> beyond the wit of man to mitigate flood damage to boats. A stocked
> boat house can easily have 250000 worth of boats so its an area worth
> lookiing at in detail.

> Anyone who is similarly interest please feel free to keep in contact.

> Regards

> Donal

 
 
 

Architectural student still has boat house design question !

Post by donal.ca.. » Thu, 20 Jan 2005 18:47:24

I have some details hidden away at home. They work on the principal
like ,say, the floating pontoon outside the ARA. They have four big
steels (appear around 1 metre diameter) piled securely into the ground
which are inside the houses and allow for (from memory) about a 3 metre
rise in water(dont know if you turn the engine on after 3 meters!!).
The firm manufacturing the houses was looking to sell several thousand
units and is a serious large engineering concern in Holland. I will try
and dig up the details at some point.

Of course a sudden rush of water would still be a problem and I also
wonder about the consequences of debris getting caught underneath on
the ride back down,

If a similar principal were applied to racking as its (relatively)
light one could have a ratchet rise so that the debris problem was
eliminated. One may need a weird and wonderful shape produced to allow
the boats to travel up into roof spaces without riggers colliding but
Id have though a decent engineer could come up with quite an elegant
solution.

Having suffered from 2 foot of water in our boat house one year(my boat
squashed on bottom rack then 5 foot of water the next year...3 of my
boats squashed its a topic Im quite interested in as I can see that if
people claim(I didnt) such risks will be uninsurable in time.

Donal

ps if anyone knows of any land available for a boat house..............

 
 
 

Architectural student still has boat house design question !

Post by Kit Davie » Thu, 20 Jan 2005 20:04:29

<snip>

Quote:
> Donal

> ps if anyone knows of any land available for a boat house..............

This is from RQs notices page. Don't know how current it is.

http://www.odsc.org.uk/mainpage.htm

Kit

 
 
 

Architectural student still has boat house design question !

Post by Phil » Fri, 21 Jan 2005 18:41:21

Perhaps I can float (!) an idea.... providing the water level doesn't
rise too quickly, and boats are routinely tied to the rack - leaving
the bungs/hatches out would surely mitigate the worst of the damage?
The bouyancy compartments would fill and empty gradually. Might be some
silt left inside which could be washed out after.

Cheers,

Phil.

Quote:

> Having suffered from 2 foot of water in our boat house one year(my
boat
> squashed on bottom rack then 5 foot of water the next year...3 of my
> boats squashed its a topic Im quite interested in as I can see that
if
> people claim(I didnt) such risks will be uninsurable in time.

 
 
 

Architectural student still has boat house design question !

Post by Sarah Farquha » Fri, 21 Jan 2005 19:13:51

boat bays found

Quote:
> themselves under a foot and a half of water. Unfortunately, Peter Brandt's
> airtight construction meant that it floated in to the underside of the
> rack above - severely cracking the shell, taking the club's new novice
> boat out of action for the second novice term in a row.

the first time it was out of action because the bows were taken off,
crashing into a corner if I am not mistaken? ;)

Sarah

 
 
 

Architectural student still has boat house design question !

Post by Douglas MacFarlan » Fri, 21 Jan 2005 19:24:30



Quote:

>Perhaps I can float (!) an idea.... providing the water level doesn't
>rise too quickly, and boats are routinely tied to the rack - leaving
>the bungs/hatches out would surely mitigate the worst of the damage?
>The bouyancy compartments would fill and empty gradually. Might be some
>silt left inside which could be washed out after.

>Cheers,

>Phil.

>> Having suffered from 2 foot of water in our boat house one year(my
>boat
>> squashed on bottom rack then 5 foot of water the next year...3 of my
>> boats squashed its a topic Im quite interested in as I can see that
>if
>> people claim(I didnt) such risks will be uninsurable in time.

Am I missing something here? If the boats are stored hull up, even
with the hatches open, will the air in the compartments not just
get a bit compressed by the pressure of the water from below rather
than expelled. What route would the air use to escape from the
compartments?

Douglas

 
 
 

Architectural student still has boat house design question !

Post by Sarah Farquha » Fri, 21 Jan 2005 19:42:37

Quote:
>>Perhaps I can float (!) an idea.... providing the water level doesn't
>>rise too quickly, and boats are routinely tied to the rack - leaving
>>the bungs/hatches out would surely mitigate the worst of the damage?
>>The bouyancy compartments would fill and empty gradually. Might be some
>>silt left inside which could be washed out after.

> Am I missing something here? If the boats are stored hull up, even
> with the hatches open, will the air in the compartments not just
> get a bit compressed by the pressure of the water from below rather
> than expelled. What route would the air use to escape from the
> compartments?

> Douglas

I agree, how would the buoyancy compartments fill up if there was
nowhere for the air to escape? its the same idea as pushing an upturned
bottle into a bucket of water - the water does not fill the bottle
because there is nowhere for the air to escape.

If you tie the boats on, then surely the place of contact with the ties
would be the first place for the shell to get damaged - just like
overtightening a tie when you put a boat on a trailer!

Sarah

 
 
 

Architectural student still has boat house design question !

Post by Phil » Fri, 21 Jan 2005 22:35:41

This might depend somewhat on the details of the construction - doing a
quick straw poll of our club sculls shows some with a vertical hatch
and a bung, some with a hatch angled along the waterchute, and some
with a horizontal hatch in the decking. Each of these would fill to a
differing degree when presented with a slowly rising water level. Some
makes of scull in the shed would fill completely (eventually) due to
their inherent inability to be watertight (or airtight!) since new.....
Phil.
 
 
 

Architectural student still has boat house design question !

Post by Sarah Farquha » Fri, 21 Jan 2005 23:33:25

Quote:

> This might depend somewhat on the details of the construction - doing a
> quick straw poll of our club sculls shows some with a vertical hatch
> and a bung, some with a hatch angled along the waterchute, and some
> with a horizontal hatch in the decking. Each of these would fill to a
> differing degree when presented with a slowly rising water level. Some
> makes of scull in the shed would fill completely (eventually) due to
> their inherent inability to be watertight (or airtight!) since new.....
> Phil.

  although that may apply to singles, I doubt the same would be true of
an VIII.

Sarah

 
 
 

Architectural student still has boat house design question !

Post by Douglas MacFarlan » Fri, 21 Jan 2005 23:49:54


Quote:


>> This might depend somewhat on the details of the construction - doing a
>> quick straw poll of our club sculls shows some with a vertical hatch
>> and a bung, some with a hatch angled along the waterchute, and some
>> with a horizontal hatch in the decking. Each of these would fill to a
>> differing degree when presented with a slowly rising water level. Some
>> makes of scull in the shed would fill completely (eventually) due to
>> their inherent inability to be watertight (or airtight!) since new.....
>> Phil.

>  although that may apply to singles, I doubt the same would be true of
>an VIII.

>Sarah

Let forget about hatches for a moment. If you had a sculling boat
which had had it canvases (let's be nostalgic as well) removed
and it was tied to a rack hull up. If the boathouse slowly flooded
would the hull fill with water? (Let's also asume that the hull
has not leaks).

Douglas

 
 
 

Architectural student still has boat house design question !

Post by Jon Anderso » Sat, 22 Jan 2005 00:01:05

Quote:

> Let forget about hatches for a moment. If you had a sculling boat
> which had had it canvases (let's be nostalgic as well) removed
> and it was tied to a rack hull up. If the boathouse slowly flooded
> would the hull fill with water? (Let's also asume that the hull
> has not leaks).

No it couldn't, could it?
The solution is to get a long piece of pipe and tape it to the floor of
the boat and when upturned feed it out so it sticks above the top of the
hull.
Or...just move the boats off the racks. :)

Jon
--


    [ All views expressed are personal unless otherwise stated ]

 
 
 

Architectural student still has boat house design question !

Post by Douglas MacFarlan » Sat, 22 Jan 2005 01:45:14


Quote:


>> Let forget about hatches for a moment. If you had a sculling boat
>> which had had it canvases (let's be nostalgic as well) removed
>> and it was tied to a rack hull up. If the boathouse slowly flooded
>> would the hull fill with water? (Let's also asume that the hull
>> has not leaks).

>No it couldn't, could it?
>The solution is to get a long piece of pipe and tape it to the floor of
>the boat and when upturned feed it out so it sticks above the top of the
>hull.
>Or...just move the boats off the racks. :)

>Jon
>--


>    [ All views expressed are personal unless otherwise stated ]

That sounds like the voice of practical experience rather than
theoretical discussion. Fortunately it is not a problem I have
had to solve for my own boat.

Cheers,

Douglas

 
 
 

Architectural student still has boat house design question !

Post by Phil » Sat, 22 Jan 2005 01:57:34

Scarcely enough trapeed air in some VIIIs to make it float!
 
 
 

Architectural student still has boat house design question !

Post by Sarah Farquha » Sat, 22 Jan 2005 02:19:32

Quote:

> Scarcely enough trapeed air in some VIIIs to make it float!

well i figured the sort of VIII in question was the type (like a
Janousek) that had sealed underseat buoyancy (but hey lets not get
embroiled with the buoyancy issue here)

Sarah

 
 
 

Architectural student still has boat house design question !

Post by petersr1.. » Sat, 22 Jan 2005 03:32:31

Quote:

> Scarcely enough trapeed air in some VIIIs to make it float!

If you've put the VIII upside down on the rack, then buoyancy when the
right way up is pretty irrelevant. It will not fill up past the highest
point where water can flow in, so the upwards force on the eight is
equal to the weight of an eight _full_ of water (canvasses and any
buoyancy compartments included) if you were to try to lift it (huge)
minus twice the weight of the eight (relatively small). So, a few tons
of upwards force.

Pete