• We invite you to join UKWorkshop.
    Members can turn off viewing Ads!

Metal profile roof sheets dripping

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

Paul TT

New member
Joined
20 Aug 2020
Messages
3
Reaction score
0
Location
Portsmouth UK
Hi I have a shed with a metal profile roof fixed straight on to timber joists with tek screws am worried about this dripping water as weather gets colder what or how can I nsulate this preferably without taking the roof off completely as I wish to store some classic motorcycles anyone done this or have an answer to this one.
 

AJB Temple

Finely figured
Joined
13 Oct 2015
Messages
3,601
Reaction score
832
Location
Tunbridge Wells
If the motorcycles are valuable, I would store them in an inflatable bubble inside your shed. This consumes very little power and is very effective at dealing with a consistent environment. As you are in Portsmouth, keeping corrosion at bay is always a challenge.

Also the units condition the battery at the same time as keeping the bubble inflated.
 

Lard

Established Member
Joined
2 Feb 2014
Messages
101
Reaction score
67
Location
Abergavenny
It will happen! I have the same although when I built my ‘shed’ I included an inner breather membrane which has ‘dealt’ with the problem of condensation droplets.........up to a point. The condensation collects On the inner side of the profiled roof, gains weight and eventually the larger droplets fall onto the membrane and run down and out. Without wishing to tell you how to suck eggs the problem is that warm, moist air hits the cold roof and so the only solution is to insulate/ventilate. Boarded insulation will help but even that will not eliminate the issue and so the ultimate answer is to spray insulate the inner face. I couldn’t be bothered with that and so I put up with the ODD (ie rare) drop making its way through the membrane joint at the laps and that’s only because I should have increased the pitch when I designed/constructed the roof.
Hope that’s of use to you.
dq
 

MikeG.

Established Member
Joined
24 Aug 2008
Messages
10,158
Reaction score
672
Location
Essex/ Suffolk border
We have a professional sheet roofer on the forum, but I've forgotten who he is. Hang on for his advice before you make any decisions.
 

disco_monkey79

Established Member
Joined
5 Oct 2009
Messages
634
Reaction score
28
I had spray foam on my old workshop's metal roof. It sorted the problem perfectly, but I had metal joists, and it also made a terrible mess when spraying it on.
 

Paul TT

New member
Joined
20 Aug 2020
Messages
3
Reaction score
0
Location
Portsmouth UK
I had spray foam on my old workshop's metal roof. It sorted the problem perfectly, but I had metal joists, and it also made a terrible mess when spraying it on.
Hi spray foam is nasty stinky stuff and would need everything emptied out was wondering what I could fit on the inside to do the same
 

Steve_Scott

Established Member
Joined
21 Jan 2019
Messages
103
Reaction score
26
Location
Huntingdon
If you could face replacing the sheets there is a product that has a fleece type material layered to the building side. It basically acts like a sponge and holds onto the water and allows it to evaporate as the day warms up (as long as you have reasonable airflow). I’ve been toying with this solution but feel if the roof is coming off why not just replace with timber and insulation...
 

philrosenberg

New member
Joined
18 Jul 2020
Messages
3
Reaction score
1
Location
UK
I would insulate with either kingspan or rockwool then board your ceiling.

There is an important point to note, any air which seeps past your insulation or percolates through your insulation will still generate condensation and this can potentially rot your roof.

To avoid this you should do both of the following

1, leave an air gap between the roof and the insulation connected to the outside world to allow condensation to evaporate and escape.
2, on the INTERIOR of your insulation fix a sheet of damp proof membrane to act as a vapour barrier. This must be sealed at the edges with tape to make it airtight. Or if you use kingspan with the shiny coating, the shiny coating is your vapour barrier. Use the silver tape to seal this at all edges and fix any damage.

So from the top, down, you should have metal roof, air gap, insulation, vapour barrier, boarding.
 

Paul TT

New member
Joined
20 Aug 2020
Messages
3
Reaction score
0
Location
Portsmouth UK
I would insulate with either kingspan or rockwool then board your ceiling.

There is an important point to note, any air which seeps past your insulation or percolates through your insulation will still generate condensation and this can potentially rot your roof.

To avoid this you should do both of the following

1, leave an air gap between the roof and the insulation connected to the outside world to allow condensation to evaporate and escape.
2, on the INTERIOR of your insulation fix a sheet of damp proof membrane to act as a vapour barrier. This must be sealed at the edges with tape to make it airtight. Or if you use kingspan with the shiny coating, the shiny coating is your vapour barrier. Use the silver tape to seal this at all edges and fix any damage.

So from the top, down, you should have metal roof, air gap, insulation, vapour barrier, boarding.
Could I foam the gaps above wooden joist with squirts foam them celotex or king spa between the joists and either foam or seal where the boards touch the joists?
 

Keith 66

Established Member
Joined
5 Jan 2013
Messages
586
Reaction score
170
Location
Benfleet Essex
Im just at the point of replacing the workshop roof but it will with be insulated steel roofing sheets, expensive but worth it.
 
Top