I've got a corrugated roof on my garage and its getting on my nerves, on the inside of the roof the amount of condensation that builds up is unbelievable it's drips everywhere n makes everything inside wet,

 

Now is there anything I can apply to the roof to stop this, don't really wanna have to put a new roof on to stop this

 

Cheers in advance Paul

I've got a corrugated roof on my garage and its getting on my nerves, on the inside of the roof the amount of condensation that builds up is unbelievable it's drips everywhere n makes everything inside wet,

 

Now is there anything I can apply to the roof to stop this, don't really wanna have to put a new roof on to stop this

 

Cheers in advance Paul

 

it needs a "warm roof void"..in english it means it needs insulating from the top(outside) so that the inside temp is room temp and not condensing. Rip them shite sheets off and deck it out with 3/4 plywood and have a normal flat roof as in felt and bitumen.Stop spending on the zed and get yourself a decent hat on the garage:laugh:

I've got a corrugated roof on my garage and its getting on my nerves, on the inside of the roof the amount of condensation that builds up is unbelievable it's drips everywhere n makes everything inside wet,

 

Now is there anything I can apply to the roof to stop this, don't really wanna have to put a new roof on to stop this

 

Cheers in advance Paul

 

I have my similar roof lined with polystyrene sheet 50mm thick. I came in 8x4 sheets and was easy to put up and or cut to fit

Some is wedged behind the roof supports. In other places I used expanding urethane foam to bond it in place.

Its not flameproof of course so it could be a fire hazard. However in a private garage on private land not accessed by the public and with no employee liability either I felt the benefits outweighed the risk. Wasnt overly expensive either.

The safer option as regards fire risk is Kingspan sheeets or similar but they are a lot more expensive.

Heh, I worked at Wards/Kingspan for 5 years inbetween semesters during my time at University. They're expensive because of how much coin the temp workers get :lol:

I thought about polystyrene I also heard you can get a paint that helps prevent it but didmt wanna buy it for it not to work

 

If I stop spending in the zed it will never get back on the road lol, I wish I would of boarded the roof now instead of using corrugated sheeting

Hi

 

I have one of them concrete garages, and they have a metal corrugated roof. When getting installed they put this sheeting underneath to stop condensation. Heres some pics. Ive never had any condensation problems yet touch wood. Not sure what its called tho.

I thought about polystyrene I also heard you can get a paint that helps prevent it but didmt wanna buy it for it not to work

 

If I stop spending in the zed it will never get back on the road lol, I wish I would of boarded the roof now instead of using corrugated sheeting

 

As said already not too expensive.

http://www.ebay.co.uk/itm/EXPANDED-POLYSTYRENE-FOAM-PACKING-SHEETS-ALL-SIZES-/251006675975?pt=UK_Packaging_Materials&var=&hash=item3a7129ec07

Just the 25mm thickness would stop condensation. The 50mm will make it quite cosy!!

I'm in a similar situation to you. However I budgeted to get a sprayfoam contractor in.

 

Been building my workshop for the last 18 months, and finally put the steel roof on in August. Pitched roof with steel z purlins going gable to gable means I have a completely open attic void with no trusses in the way. Lots of storage!

 

Anyway I researched insulation options quite extensively. Apparently difference of around 1-2 degrees between the inside air and the outside will cause condensation.

 

 

You have several options which I'll list worst to best:

 

1) EPS sheet cut to fit

 

Will work BUT will be flush against the valley on the corrugated sheet. This means the crest of the sheet is forming a void above the eps panel. Air will get in there either from inside or outside and it will still condensate. If it gets really bad it'll drip down onto the eps and run down until it find an exit. Every joint needs to be taped to stop the air going up through to the roof sheet.

 

The other major issue is fire - even the fire retardant stuff burns real bad. An angle grinder spark will just go straight through it.

 

 

2)

 

Foil backed Kingspan style stuff

 

Easier to work with than the EPS, better fire ratings too. Foil backing means that you can tape the joints much easier and effectively and in doing so you form a 'vapour barrier.' Very expensive though

 

 

3)

 

DIY sprayfoam

 

Very effective - it will get into every gap in the roof and seal it. It's 'closed-cell' foam meaning it is waterproof. You will end up with a well insulated warm roof.

 

It looks easy to apply but I bet its not! :)

Bad news - diy spray foam kits have no fire rating! The stuff you see online that says this and that about fire actually refers to a German B1 rating which is basically means it will combust/ignite

 

 

4)

 

Contractor installed sprayfoam

 

Get a pro in and you can have british standard class 0 fire rated foam. Hold a blow lamp on and it'll melt but not catch fire.

 

Cost is not exactly cheap - I've had quotes for 60m2 at 50mm thick range from £1300 - £2500. They all tell me they would have my roof done in 1/2 a day.

 

 

Funny angle photo of my roof below

 

You could use building visqueen ( I think thats how it's spelt). I had the same trouble on my old garage so I did a nice install over the top in black sheet. Used stainless staples to fix it to wood batons on the top of the walls outside then stretched it over to the other side. Did the same front and back and the condensation stopped. Very good temporary measure for the winter but make sure you fix it on very well indeed otherwise it'll blow up like a kite and disappear into the neighbours garden. If I remember it was about £50 for miles of the stuff. Beofre I did this I spent money on black bitchumen paint on the outside of the panels but it didn't stop the condensation.

Hmmm thanks everyone got a few ideas now,

 

Cheers dublove some good info there

That sprayfoam is very good, I am in the process of refurbishing someone's workshop and just had a contractor in to do the inside of the new tin roof, it works a treat. Not sure how much it would be for something small or diy but definately does the job and doesn't take long to do at all.

hey eggs - says you're in somerset, can you tell me who you used for the foam? I've found only one place local'ish to me (Cosyhome in Glos) all the others seem to based up north!

I had this done in Norwich but the company came from up North, Hull rings a bell. Im away so can't get to any paperwork at the moment, if you need to know let me know and i'll dig it out when im back next bud