As you could have read under types of houseboats, only the 'arks'
on a concrete hull are blessed with an almost maintenance-free
under-water-ship. All ships on a steel or iron hull must be taken out of the
water every three or four years for treatment against the inavoidable rust and
to be checked for signs of wear and tear.|
Ships that still sail wear off
faster than permanently moored houseboats and the maintenance interval mostly
depends on conditions in the insurance policy or the mooring permit.
The most popular ways of getting ships out of the water are the slipway and the
drydock. In some cases a hoisting crane or boatlift is used, but only for the
A slipway is a kind of railway track which runs down a slope till under water.
On it are several special carts, moved by a winch. The carts are lowered in to
the water, the ship is manoeuvered above them and then secured with ropes. Once
everything is in place the winch pulls the carts with the ship on to dry land.
To make it clear i've drawn a
sketch of a slipway (GIF 7Kb).
In a drydock a ship comes out of the water straight up, which is very practical because then you won't have to empty all the shelves and cupboards in the house to avoid mayor
household disasters. A drydock is in itself a large container. Once the ship
has entered the dock can be pumped dry and the work can begin. A fixed dock is
shut with watertight doors before pumping and a floating dock is so to speak
A floating dock is a sort of submersible barge. It is sunk
far enough to allow the ship to be manoeuvred in. Then pumps start to
bring the two above the water.
I've also made a drawing of a floating dock(GIF 8Kb) .
Once a ship is out of the water it is cleaned with water under heigh pressure,
more than 100 atmosphere (1470 psi) to get rid of waterplants, alge and stuff
like small shellfish. Then the hull can be inspected.
The first inspection
is a visual one for deep rust and/or loose rivets. Then a ship is often
'knocked', hit on with a big hammer to hear (frequency) and feel (buoyancy)
whether the plates are still thick enough. The required amount of plate differs
on the use of the ship and on the insurance company, in general 3 to 4 millimeters
is considered good for a permantly moored houseboat.In some cases a ship has to
be measured for thickness. The old way consists of drilling holes on supicious
spots and measuring the plate. Nowadays a lot of inspectors have ultrasonic
measuring devices which only require thourough cleaning at the spots to be
As soon as the ship is found in order or is repaired it gets coated for the next four
years. Until recently with tar or tar-containing products, but this will soon
be over due to new environmental regulations. Unfortunately the quality of the
given alternatves is not proven yet. New regulations do bring up the price
because shipyards have to meet tougher requirements.
Don't get me wrong, I do support environmental improvements but find it sad to
see that it will probabely mean for some people that they'll have to leave
their floating house because they cannot afford the maintenance anymore. The new rules
may also mean the dissapearance of some characteristic small shipyards in
Going to the shipyard is probably the biggest and most costly event that
regularly returns.You're out of a house for a week, or can camp in it on the
shipyard, without water, gas and telephone. The costs can add up to 2.000 Euro
and that is if everything is o.k. Repairs vary from 300 to thousands of
Euros. On top of that you have to take a leave from your work because you
have (or want) to be present wen repairs or inspections are carried out.
Welding and grinding for instance, bring along an increased fire-hazard.
But, if all goes well it brings you years of house-boating-fun and freedom!