Condensation again, but on a new build

[WotEver]

18 minutes ago, Alan de Enfield said:

The man that never made a mistake, never made anything.

And the man who’s never experienced failure has never risked anything. 

[Kendorr]

1 minute ago, WotEver said:

And the man who’s never experienced failure has never risked anything. 

Strewth, I've led a very risky life then ?

[ditchcrawler]

20 minutes ago, matty40s said:

The boat I mentioned in a different thread *should I have a survey on a new boat.....

I moved in Winter,  ending up breaking thin ice occasionally.

The boat was dripping inside,  on closer inspection,  the spray foam had only been sprayed up to the under window cross members and the steel round the windows was uninsulated.

The spray foam stopped 3" from every mushroom hole.

Steel with a single coat of paint was visible round all hatches and front mini-doors, the wood hadn't been built out far enough and rust was already visible in all these areas.

I had to get them back to mine, it was as thin as a coat of paint in some places, needles to say after they did it again I had a lot of cutting back to do

[Old Son]

10 hours ago, Markinaboat said:

Two houdini hatches dripping from the metal frames. Was thinking of using a piece of ply, maybe 6mm glued to kingspan and then covered with vinyl and pushed up with a tight fit under the hatches. Has anyone tried this or similar method?

I've made two boxes, one for each hatch which sit on the roof. They are painted to match the roof cover and sit in place when I'm not on the boat. I move them when on the move. Absolutely no dampness around them. I did also make a wooden frame with some stick on foam around the outside. The frame sat tight into the hatch surround. The frame incorporated a piece of polycarbonate to allow the light through. It works and keeps the metal frame dry but I like the protection the external box provided. 

[Batavia]

13 hours ago, Mike the Boilerman said:

I too have a condensation problem on bare steel. Or my boat does anyway 

 

Its on the undersides of the sliding hatches front and back. As the hatches slide they go over a steel ledge/upstand which would prevent sprayfoam getting past. I can only add 2mm or perhaps 3mm thickness of insulation. Any suggestions? Whatever I might use, the OP could use the same. 

 

I always used foam board on the underside of sliding hatches. It has an impervious surface which can be wiped clean and comes in thicknesses from 1mm upwards.  You can get a self-adhesive version, but I always used a contact adhesive - enjoy the fumes!

 

Chris G

[ditchcrawler]

3 hours ago, Batavia said:

I always used foam board on the underside of sliding hatches. It has an impervious surface which can be wiped clean and comes in thicknesses from 1mm upwards.  You can get a self-adhesive version, but I always used a contact adhesive - enjoy the fumes!

 

Chris G

My side doors are done with that as they are open in all weathers

[Markinaboat]

14 hours ago, Old Son said:

I've made two boxes, one for each hatch which sit on the roof. They are painted to match the roof cover and sit in place when I'm not on the boat. I move them when on the move. Absolutely no dampness around them. I did also make a wooden frame with some stick on foam around the outside. The frame sat tight into the hatch surround. The frame incorporated a piece of polycarbonate to allow the light through. It works and keeps the metal frame dry but I like the protection the external box provided. 

found this today. B&Q sell, Wickes have their own version. Can also get plastic end covers to finish off. Thought woold buy some magnetic tape to hold under the houdini hatches.

 

http://www.arielplastics.com/en-gb/products/multiwall-polycarbonate/multiwall-polycarbonate-sheet/10mm-twinwall.aspx

[Guest]

On 13/12/2018 at 17:11, Mike the Boilerman said:

I too have a condensation problem on bare steel. Or my boat does anyway 

 

Its on the undersides of the sliding hatches front and back. As the hatches slide they go over a steel ledge/upstand which would prevent sprayfoam getting past. I can only add 2mm or perhaps 3mm thickness of insulation. Any suggestions? Whatever I might use, the OP could use the same. 

 

 

 

 

 

 

 

Had exactly the same problem as you, and glued some of that foam camping sleeping mat on the underside of the hatches which has worked well (six quid at argos). I think it is more than 3mm, but you might be able to get a thinner foam of similar nature? 
 

[ditchcrawler]

25 minutes ago, catweasel said:

Had exactly the same problem as you, and glued some of that foam camping sleeping mat on the underside of the hatches which has worked well (six quid at argos). I think it is more than 3mm, but you might be able to get a thinner foam of similar nature? 
 

https://www.ebay.co.uk/bhp/3mm-pvc-sheet upvc foam sheet

[Guest]

On a slightly different note, I am this year getting a condensation problem that is worse than other years. It is the old "mattress against the wooden wall" problem! The short term solution seems to be leaving a moderate gap between mattress and panel, though this is not ideal. I have tried the "camping mat" approach between panel and wall, but this seemed to make things worse. 
It is a standard spray foam insulation, with an air gap, then 9mm ply panels.  My thoughts have included injecting more expanding foam in there, and/or spray gluing carpet tiles to the wall. I wondered if anybody else had tried these or other approaches with any success?
Mucho grassyarse.

[ditchcrawler]

2 minutes ago, catweasel said:

On a slightly different note, I am this year getting a condensation problem that is worse than other years. It is the old "mattress against the wooden wall" problem! The short term solution seems to be leaving a moderate gap between mattress and panel, though this is not ideal. I have tried the "camping mat" approach between panel and wall, but this seemed to make things worse. 
It is a standard spray foam insulation, with an air gap, then 9mm ply panels.  My thoughts have included injecting more expanding foam in there, and/or spray gluing carpet tiles to the wall. I wondered if anybody else had tried these or other approaches with any success?
Mucho grassyarse.

The carpet bit fixed it for me.

[Cheese]

If getting foam, try and get something that is fire resistant.  The last thing you want in an emergency is molten plastic dripping from an exit route.

[TheBiscuits]

1 hour ago, Cheese said:

If getting foam, try and get something that is fire resistant.  The last thing you want in an emergency is molten plastic dripping from an exit route.

It's not a bad thought, but if the fire was making the foam drip off that hatch I think I'd want to go out the other way.

[Guest]

6 hours ago, ditchcrawler said:

The carpet bit fixed it for me.

Thanks will give it a go. May I ask if you used spray adhesive or similar?
Cheers.

[ditchcrawler]

8 minutes ago, catweasel said:

Thanks will give it a go. May I ask if you used spray adhesive or similar?
Cheers.

Yes, spray

[Guest]

Just now, ditchcrawler said:

Yes, spray

Superb, thanks. A trip to Wickes or similar for me tomorrow

[BruceinSanity]

13 hours ago, ditchcrawler said:

Yes, spray

We’ve used carpet tile in difficult, badly ventilated spots, mainly inside lockers. We found using double sided tape as well as spray helped keep the tiles in position.