tin roof sealant?

[johnakay]

I got sick of getting my garage roof refelted so I bought some Box Profile Roof Sheets.
the ones that are coated in brown or green plastic etc..
when it snows like it has been water tend to seep up through the joint.
I don't get this problem when it rains only when it snows.
ok it not the snow that cause it but ice,when it start to melt the water can't get through quick enough so it forms a puddle in the roof and seep throught the joint.
the question is what the best sealant to use?
I want one that doesn't crack etc with hot/cold weather.

 

[Paul.]

Roofers mate is pretty good, only available in black and grey though, it sets like rubber, very flexible.

 

[CTB]

Ideally if you could raise the pitch of your roof to above 10 degrees, you wont have the ice problem.

 

[pedrobedro]

I sealed between the sheets with roofing mastic as I fitted the roof. If you have the recommended overlap it should seal alright.

 

[johnakay]

Ideally if you could raise the pitch of your roof to above 10 degrees, you wont have the ice problem.

I knew that years ago when I had the garage built.
the neighbour was a bricky and he did all the drawings/planning etc.
I didn't want to interfere .on the drawing (and I still have it it) state a 5" drop to zero. I thought this wasn't much but he said that is standard for a garage(in 1979 when I had it built)
cost me about £1,000 @ the time this inc the 30/40ft drive ,garage 21ft x 12ft wide .
the builders wanted £1200 for a small garage 14ft x 10ft .
so I didn't argue about the slope.the chap is dead now.

 

[CTB]

In my experience, soaking the roof with those black bitumen products never brings a satisfactory result. The water ingress caused by an ice dam always finds a way through. Its better to bite the bullet and raise an end to at least a 15 degree slope , and it will be cheaper in the long run.

 

[Ratty]

so I didn't argue about the slope.the chap is dead now.

That was a bit harsh

Sikaflex 291 is good, marine grade and fast set in cartridge form. Not sure about this one but there are a lot of PU sealants that are moisture cure and don't mind damp surfaces if you want to get it done ASAP. Try googling. Sikaflex are a pretty good make and they may do one more suitable.

 

[Hitch]

Sika291, excellent quality sealant...used a good few tubes of that!

For cladding, a butyl rubber is normaly used, such as the alreday mentioned roofers mate, much cheaper than sikaflex.

For side laps, polyband tape is normally used, composite sheets are supplied with it already applied iirc.

 

[decepticon]

For cladding, a butyl rubber is normaly used, such as the alreday mentioned roofers mate, much cheaper than sikaflex.

butyl mastic is what is recommended for side and end laps but comes on a roll (9x3mm) as a strip not from gun applied tube

For side laps, polyband tape is normally used, composite sheets are supplied with it already applied iirc.

poly band is for side laps but not on the weathering sheet. it is used in a twin skin system to make the liner panel sidelaps airtight.
composite sheets used to have an integral seal but they now recommend 9x3mm butyl strip sealant site applied

it could well be that if it is a single skin roof the ice/snow could be causing condensation
cheers
neil