marine head

[Tigerlily]

Can anyone guess at how much it would cost to install a marine head with holding tank in an older boat?

That is a rather vague question. You may as well ask how much does a sail boat cost.
I am currently building the head in my trimaran, and I can tell you what I have found, but you could do it cheaper, or spend lot's more.
Head-$315
Holding Tank-$80
misc fittings-$60
1.5" thru hull-$30
3/4" thru hull-$16
Seacock 1.5"w/flange-$100.00
3/4" thru hull-$42
Y-Valve-$63
anti siphon-$35
macerater pump-$150
Deck Fitting-$40
1.5" hose-$100
3/4" hose$20
Misc clamps and such depends on what you use
or
Porta potti-$70

[Alan Wheeler]

Then Add 150% as a fudge factor, just because it's a boat.

[By Invitation]

Alan,

Your being conserative again.

[Alan Wheeler]

Welll, I don't want to put the guy off compleatly.

Actually, if you are going to pay someone to do the work, just add a zero to each of my figures, and you should be close
Or as the standard boatright statement around here goes "6 weeks and $15000". It does not matter what stage of what project you ask about, that is the answer.

[Alan Wheeler]

Now for a little clarification, just for interest sake. A Toilet is a toilet, not a Head. "The Head" is the head of the boat. The area just beyond the figure "head". A toilet is only called a "head" if it is installed at the head of the boat. The term "Head" used today is actually falsely used.
Quoted from Colin Brookes.

[Jentine]

will only cost a couple of bucks.

As I have pointed out many times, I am a fan of the bucket, however. It's hard to get women on board without a head. And Wheels, I know, but as I have also said before, misnomers can become accepted language over time, through common usage. This is one of them.
While we are talking toilets, anyone have any experience with Lavacs? I have used the Taylors stuff, and really like the quality, but I have concerns about the seal on the Lavac head. I am considering this for a future installation. I can not find ny warranty info online for this toilet. Anyone know the warrany period?

[Boracay]

I put a Lavac onto my 32' ferro some time ago.
It worked well with no problems at all.
Thats provided you dont count the reactions of one sensitive lass who was horrified to see the toilet paper from her visit streaming out from the boat.

[delmarrey]

According to the Sailor's Illustrated Dictionary: head n. (1) The toilet on a vessel. Today the term is often used to mean the space in which the toilet, basin and other conveniences are found. The use of this definition comes form the days when the crew relieved themselves standing on a wooden grating near the water's edge at the bow or head of the ship. To go to the head was quite literally to go to the head of the ship. (piss'n into the wind)

Sometimes called the john................_/)

[GordMay]

FWIW: Plumbers & Mech. Engineers call the 'toilet' the “Water Closet” (WC), and the 'sink' the "Lavatory" (LAV)

[BC Mike]

The WC on the plans contains the lavatory ( dunny ) and the water closet, which may be the water container for flushing the dunny, or it may be a water tank up higher for the same purpose, or the tank could be a holding tank to gravity feed the taps. The sink for hand washing is often in another room and not in the WC area but in the bathroom. Possibly different usage of terms in different areas. I am giving you the Queens English version.
Many British magazines now refer to the general area that may contain the dunny and sink as the heads. Prural and I am not sure why. Maybe someone still living in England can explain how the British messed that up. Can I assume that lew is short for lavatory ?
NZ English being more refined, will refer to the dunny / toilet / head / can / bucket by what is going on in there. So you can have a slash house or a bog shop, depending on the activity.
Michael

[Boracay]

From memory the only problem with installing a Lavac (and this would probably apply to most marine toilets) was doing a good seacock installation.
With good quality seacocks properly installed all one had to do was install a tiny anti siphon hole a suitable distance above the waterline in a loop of the sea water input pipe and make sure the hoses were fully secure. It is necessary to ensure that the anti siphon hole is never blocked.
I also thought it desirable to make sure the auminium body of the toilet was bolted securely to a solid wood base. A ceramic body would need special consideration.
The Lavac is a most satisfying toilet to use as one simply lowers the lid, gives a number of solid pumps, and listens for the hiss of the anti siphon. All is then well.
One should, of couse, never operate the pump while sitting on the toilet as medical attention could be a long way away, and emergency rooms would have little experience of the resulting bodily damage.
These days it seems mandatory in many places to run the output to a holding tank. Some places seem to require pumping from a deck fitting, some sort of diversion scheme and some sort of lock. It would be best to check local regulations. The holding tank would require a suitable vent.
Like most things on a boat it may be sensible to assemble all the components in the desired position and have a long, careful think.

It's interesting that you mention the pump out. Due to the fact that the Lavac is a sels system from intake to output, during a pumpout, if the seat is closed, is it reasonable to assume that the tank will be filled with seawater? And is it also reasonable to assume that if the seacock is closed for the intake, that it will likely cause the tank to collapse, or other damage? And finally, does Lavac provide any specific guidelines for this?
Finally, my biggest concern is still the life of the lid seal. Has anyone had one fail?