Cladding

[Paul Gwilliams]

Please see the pictures of some cladding at the rear of the cabin on our 30' Mike Siveright owl class NB.

 

I took one side apart to remove the gas piping and noticed there was a lot of air / dead space in there.

 

My question, or rather can you help settle a difference of opinion between the boss and me, is can I lose some of the height as on one side I want to put an additional step in and on the other by lowering the level I will have less adjusting of a new kitchen unit to do

[Tony Brooks]

I am baffled by the photo. If the varnished wood is under the gunwale then the plastic tub is defying gravity. If the plastic tub is not defying gravity I can't work out what the step is with the white bar thing on it. However I am not familiar with those boats.

[Hudds Lad]

21 minutes ago, Tony Brooks said:

I am baffled by the photo. If the varnished wood is under the gunwale then the plastic tub is defying gravity. If the plastic tub is not defying gravity I can't work out what the step is with the white bar thing on it. However I am not familiar with those boats.

pretty sure it's the panels around the swim at the back end near the step up to the stern, top pic is taken at an angle and is the left side if looking to the stern from indoors, bottom pic is right side.

 

or i'm completely wrong

[Tracy D'arth]

Looks like the rear swim to me too. Don't remove it!

[Tony Brooks]

2 minutes ago, Hudds Lad said:

pretty sure it's the panels around the swim at the back end near the step up to the stern, top pic is taken at an angle and is the left side if looking to the stern from indoors, bottom pic is right side.

 

or i'm completely wrong

I thought it was one photo but still baffled. I did think the "box" in lower part of the image looked like the curve of a swim but it did not look tall enough to me even given the floor is in place so maybe 4" or so taller than it looks.

 

Maybe more individual photos annotated to show what he wants to do. I don't think trying to lower the swim is very practical or even sensible.

[David Mack]

If you take that cladding off you will find insulation behind it, then a few mm of steel and then canal water. Its the shape of the hull. Lift up that floor panel, and all should become clear.

[Paul Gwilliams]

It is the cladding on the swim.

 

However when I removed the top on the right side (blue frame of door seen in photo) there was a good 4 to 5 inches of air then a layer of polystyrene insulation then metal then water at various depths.

 

My question is does the airgap serve a purpose that I don't know about or can I lower the level on both sides to make an extra step for the entrance as the floor has been damaged by years of it being the spot everyone lands on as there is no internal step and on the other side lowering the height so I do not have to cut too much off a kitchen unit to follow the swim.

2 hours ago, Tony Brooks said:

I am baffled by the photo. If the varnished wood is under the gunwale then the plastic tub is defying gravity. If the plastic tub is not defying gravity I can't work out what the step is with the white bar thing on it. However I am not familiar with those boats.

The plastic tub is the location of the bottom external step

[Tracy D'arth]

Fine, go for it. Air gap is serving no purpose.

[Paul Gwilliams]

29 minutes ago, Tracy D'arth said:

Fine, go for it. Air gap is serving no purpose.

Thank you ?

[Tony Brooks]

47 minutes ago, Tracy D'arth said:

Fine, go for it. Air gap is serving no purpose.

Fully agree. Try to ensure the insulation is a tight fit against the steel and fill any gaps or cover with aluminium tape to keep water vapour away from the steel.

[blackrose]

On 11/09/2020 at 13:11, Tracy D'arth said:

Fine, go for it. Air gap is serving no purpose.

 

The airgap behind panelling in the cabin serves no purpose either but there's a myth amongst quite a few narrowboaters that air circulates in the gap and it performs some function. It's nonsense. If there's no airgap there in the first place then there's no need for air to circulate!

 

I filled the gap behind the panels under the gunwales on my boat with more insulation 15 years ago and the only effect it's had is keeping the boat warmer in winter. I know lots of people who filled the gaps between the sprayfoam and panel with rockwool during their fit out. 

[BEngo]

Tony's point about keeping the water vapour away from the steel is very important.  You already have some  water on the steel and that will tend to promote rust on the inside of the boat.  Because most boats sit nose up the water from condensation  tends to pool at the rear of the boat, usually on the counter plate.  Here the rust attacks the outside of the rudder tube, the top of the counter and, if it is there, the front of fuel tank.  It is not unknown for boats to have rusted away from the inside before they have rusted from the outside.

Whilst you have the cladding off, dry it all out, treat any rust, give it all a good coat of paint  and refit with a vapour barrier.  Spray foam in tins is a good way of gap filling. Builders polythene sheet and duct tape or, better, aluminium tape makes a great vapour barrier.

 

N

[Paul Gwilliams]

Thank you all for your input.

 

You never know with things like this whether it's cosmetic or has some purpose that was lost in the mists of time