Roof paint colour - light or dark?

[Guest]

2 hours ago, rgreg said:

I have had both light and dark roof colours. The light roof can be dazzling in the sun and hard to keep clean so I much prefer the darker colour. As for heat, I have not noticed any significant difference between the two.

I have often wondered about this. My mince pies are dodgy and I find myself reaching for sun specs more and more these days, but I think a really light coloured roof would drive me insane whilst steering in summer. I expect a matt finish might not be quite as bad.

Edited December 15, 2018 by Guest

[Dav and Pen]

With temperatures reaching 40c a lighter coloured roof makes sense but it still gets very hot. Our narrow boats were always red oxide which is very easy to apply and good for climbing on something we don’t need to do on the continent.

some of the French commercials just use a varnish over bare steel and boy do the side decks get hot. Once moored alongside one who had this system and when I lifted the dog up ,so we could cross the peniche to get off ,he stated hopping about his feet were burning. 

[The Welsh Cruiser]

Regarding various replies to changing my roof from red to light grey and not noticing any difference in summer: The insulation on my boat is poor, it's only an inch or so of polystyrene. The boat gets cold in the winter. Right now with it being around 2 degrees outside I'm having quite a job keeping the inside at 20 with my boatman stove, and I'm only 35ft. So, with the insulation being poor, if changing the roof colour to a lighter shade makes a difference I would have expected a good result with my boat, with having poor insulation. Does that make sense? 

[TheBiscuits]

2 minutes ago, The Welsh Cruiser said:

Regarding various replies to changing my roof from red to light grey and not noticing any difference in summer: The insulation on my boat is poor, it's only an inch or so of polystyrene. The boat gets cold in the winter. Right now with it being around 2 degrees outside I'm having quite a job keeping the inside at 20 with my boatman stove, and I'm only 35ft. So, with the insulation being poor, if changing the roof colour to a lighter shade makes a difference I would have expected a good result with my boat, with having poor insulation. Does that make sense? 

Yes, lots.

[The Welsh Cruiser]

2 minutes ago, TheBiscuits said:

Yes, lots.

I know it's not conclusive. I was surprised actually, because if I touch the roof of the boat at mid day it's quite cool whereas later in the day if the sun is on one side of the boat (mid green) it feels really hot to the touch.

[Sea Dog]

9 hours ago, ditchcrawler said:

The paint is Epiphany's if I have spilt it write 

'Allo 'allo, I am suspicting you tooped that on your smurt fern, Dutch crewler?

[Sea Dog]

9 hours ago, ditchcrawler said:

The paint is Epiphany's if I have spilt it write 

'Allo 'allo, I am suspicting you tooped that on your smurt fern, Dutch crewler.

9 hours ago, ditchcrawler said:

The paint is Epiphany's if I have spilt it write 

'Allo 'allo, I am suspicting you tooped that on your smurt fern, Dutch crewler.

[Greyladyx]

Having been a vehicle refinisher, one thing I do know is anything matt gets very dirty quickly and does not age well.

 

Semi gloss is good in my roof, have a look at symphony paints.

 

Gloss is often used in light colours with antislip patches masked off.(safe yes)

Edited December 15, 2018 by Greyladyx

[ditchcrawler]

14 minutes ago, Greyladyx said:

 .

 

Gloss is often used in light colours with antislip patches masked off.(safe yes)

That really holds the muck

[Sea Dog]

28 minutes ago, Greyladyx said:

...with antislip patches masked off.

 

I've got nicotine patches on my roof - it helps stop the chimney smoking.

[Greyladyx]

1 minute ago, Sea Dog said:

 

I've got nicotine patches on my roof - it helps stop the chimney smoking.

Hehe

[Dr Bob]

This summer, my dark blue roof (matt & rust finish) was getting up to 65-70°C on a sunny day which meant 31°C on the inside of the roof. Yes, that was hot inside the boat but with a good fan it was no problem. We are just having it repainted and going for a dark blue roof again. I couldnt bear the glare off a light coloured roof when motoring into the sun - the dark roof is so much better. In the winter the roof is often 25°C on the inside and 0°C on the outside. Pretty similar temperature gradients.

[MtB]

1 hour ago, Dr Bob said:

This summer, my dark blue roof (matt & rust finish) was getting up to 65-70°C on a sunny day which meant 31°C on the inside of the roof. Yes, that was hot inside the boat but with a good fan it was no problem. We are just having it repainted and going for a dark blue roof again. I couldnt bear the glare off a light coloured roof when motoring into the sun - the dark roof is so much better. In the winter the roof is often 25°C on the inside and 0°C on the outside. Pretty similar temperature gradients.

 

Another approach favoured by certain liveaboards is to cover your roof with crap. Then the colour doesn't matter one jot.

 

 

[frahkn]

2 hours ago, Mike the Boilerman said:

 

Another approach favoured by certain liveaboards is to cover your roof with crap. Then the colour doesn't matter one jot.

 

 

 

We spend about half the year on the boat but have nothing (if you ignore three pigeon boxes and two solar panels) on the roof. I can't imagine this changing were we to also spend the remaining six months aboard.

[MtB]

5 minutes ago, frahkn said:

 

We spend about half the year on the boat but have nothing (if you ignore three pigeon boxes and two solar panels) on the roof. I can't imagine this changing were we to also spend the remaining six months aboard.

 

Yep me too. Nothing on my roof except stuff used for cruising. I really couldn't imagine cruising with a roof piled high with carp, but many do. 

 

Why are you awake  and posting on here so late?????

 

Errrr.....

[Greyladyx]

Just now, Mike the Boilerman said:

 

Yep me too. Nothing on my roof except stuff used for cruising. I really couldn't imagine cruising with a roof piled high with carp, but many do. 

 

Why are you awake  and posting on here so late?????

 

Errrr.....

? 《 

[MtB]

3 minutes ago, Greyladyx said:

? 《 

 

Frahkn started it miss, Its all his fault....

 

 

[Greyladyx]

Just now, Mike the Boilerman said:

 

Frahkn started it miss, Its all his fault....

 

 

I don't speak German sorry Mike.

[MtB]

2 minutes ago, Greyladyx said:

I don't speak German sorry Mike.

 

You don't haff to. Check post 64!

[Grassman]

 

Thank you all (those of you who kept to the topic) for your helpful and thought provoking replies to my OP. I have still to decide but I'm now leaning towards having a lighter coloured roof.  The insulation on my boat is polystyrene which probably isn't as good an insulator as spray foam so that doesn't help. I have 3 solar panels and a roof box which would shelter some of the roof from the sun though, but being a 62ft boat there's still a lot of the roof exposed to the sun.

 

Since beginning this thread my wife has told me that when working the locks she has noticed a significant difference when she has placed her hand on the white and black painted balance beams. The black part is always much hotter to touch she says. 

[Dr Bob]

5 hours ago, Mike the Boilerman said:

. I really couldn't imagine cruising with a roof piled high with carp, but many do. 

 

We don't have any fish on our roof but in summer &autumn we have a few big pots of confetti ........... or Nemisia to them who are in the know....and the odd Sky dish/ TV antenna etc

[frahkn]

9 hours ago, Mike the Boilerman said:

 

Yep me too. Nothing on my roof except stuff used for cruising. I really couldn't imagine cruising with a roof piled high with carp, but many do. 

 

Why are you awake  and posting on here so late?????

 

Errrr.....

 

Well I was posting "so late" because I was awake. Why I was "awake so late" is a more difficult question .... in fact too difficult for me right now. Might have been able to answer it if I'd had more sleep last night! ?

[Dr Bob]

44 minutes ago, frahkn said:

 

Well I was posting "so late" because I was awake. Why I was "awake so late" is a more difficult question .... in fact too difficult for me right now. Might have been able to answer it if I'd had more sleep last night! ?

You didnt leave the duvet on the roof again did you?

[frahkn]

39 minutes ago, Dr Bob said:

You didnt leave the duvet on the roof again did you?

No, I distinctly remember throwing the dog off my side of the bed, pulling the duvet up and climbing under it. Also remember feigning sleep when the wife was disturbed by 5 stone of dog getting back up, on her side of the bed.

 

Almost certainly, none of this occurred on the roof, for one thing it's far too steep up there.

[Tony Brooks]

On 15/12/2018 at 12:19, catweasel said:

I have often wondered about this. My mince pies are dodgy and I find myself reaching for sun specs more and more these days, but I think a really light coloured roof would drive me insane whilst steering in summer. I expect a matt finish might not be quite as bad.

FWIW. My roof is a light grey/creamy colour but its semi-gloss over textured Protectacoat. I do not find it dazzles in the sun Is fairly easy to keep clean unless you let bird poo dry on it for months, and it is cooler to the touch than the gloss dark green band either side of the roof (the painter's choice, not mine - no consultation).