Hot tin roof?

[T i m]

Hi All,

I asked a while back about considerations when raising the pitch on a garage / workshop roof (to make more of a 'loft' / storage space) and I'm now, after seeing some in use, considering that pre coloured galv steel roofing you often see in the bigger profiles cladding the walls and roofs of the sheds we all know and love. ;-)

I'm told it would be much noisier than the existing corrugated cement fibre (and I would have to replace that anyway as it would be too short with a higher pitch) but I see you can get self insulated panels but not sure if they meet the requirements of 'non combustible' (I'm thinking of the insulation rather than the panels here).

I've even seen (but now can't find) a simulated slate (I've found the tile one) that would be in keeping with our and many of the houses round here.

The pro's for me could be that it might be lighter than cement fibre (easier for me to do), possibly more secure (you couldn't just break it open) and could be pre-insulated?

So, has anyone here used such stuff themselves and can point out any pitfalls etc please?

All the best ..

T i m

[The Natural Philosopher]

I've lived in tin tops in africa. BOY they get hot.

Definitely put insulation under.

Don't worry about noise. Just make sure there is something inside in the way of e.g. plasterboard - that will cut the echoes down.

[Mary Fisher]

Speak for yourself ...

Why not go the whole hog and use pv tiles ;-)

Mary

[Stephen Howard]

I work under an Ali one in Hants....and boy did that get hot last year!

Regards,

[T i m]

Hmm, so are we saying much hotter than corrugated cement fibre guys (assuming no insulation)?

All the best ..

T i m

[Stephen Howard]

Yeah, I would say so.

Regards,

[The Natural Philosopher]

I fear so, yes.

[T i m]

I was using the 'we' to specifically only include normal people Mary. ;-)

Whilst that would be lovely, being able to keep all the motorbikes charged up an have some battery / LV lighting etc I can't afford the panels. :-(

Al the vest ..

T i m

[Tim Lamb]

In message , T i m writes

try [e-mail]

I used their 80mm AS35 foam sandwich for a large, pitched roof workshop without any real problems.

Points to consider are....

the sheets arrive cut to length: one end square and the other having a 50mm rain drip (insulation and under sheet cut back). When you fix this as a lean-too or ridge there is a triangle of uninsulated space which needs filling with fire rated expanding foam.

flashing is made to your specification but sits on top of the roofing ribs. Metre wide foam gap fillers are available but need to be trapped by the flashing fixing screws.

Fixing screws are available for metal or wooden purlins.

rolls of mastic tape are required to prevent heavy rain bouncing under the lap joins. This is applied to the underside of the lap but requires care when lifting the sheet into position. Pair of hands needed at top and bottom. Lap stitching screws are essential.

The biggest problem I encountered was how to attach the guttering and how to seal off the exposed foam. Steadmans did not offer any solutions. In the end I got some 100mm x 75mm pine cut diagonally (done by my timber supplier with a band saw) which suited my roof pitch. Fixing was by some home made *Z* shaped galvanised steel strips and the wood dosed with preservative.

Things you may not realise about ribbed roofing..... not all buildings are built square, my barn is 1m longer on one side than the other. This is not a problem where the gutter is longer than the ridge however, on the other side, the ribs conduct rain water over the end of the building. Luckily I had some left over extruded aluminium gutter from a greenhouse which was fitted behind the flashing.

regards

[meow2222]

corrie is relatively noisy in the rain, but I dont see it being an issue.

NT

[Stephen Howard]

It can be...when you're on the phone. It also tends to amplify the intensity of the rain...it sounds like Armageddon has arrived early, and when you open the shed door to take a peek at the spectacle you find it's just a light shower. As for hail, well, that just gets silly.

Regards,

[T i m]

Brilliant. That was one of the profiles I considered (I spotted it on another site). Can you remember roughly how much it cost please Tim?

Gotcha. I wondered how you / they dealt with that ..

Understood.

And considering the up to down ratio on that profile there would be some fairly considerable sized gaps! It was that area that started my questions previously. The existing low pitched roof came with a pre moulded cement fibre ridge and that excludes all but the smallest of gappage at the ridge. I wasn't sure if this was a common solution that was available in a variety of angles but as yet I'm still not sure.

Understood.

Ok ..

Understood and ok again ..

Isn't that strange. They make a product then sort of run out of ideas on how to use it?

Ok ..

Yeah, I guess that's bound to happen quite often, especially with older buildings.

Handy. ;-)

I was thinking of building a little forward overhang into the replacement roof to offer a bit of cover over the doors so would also have to do something gutterwize.

I guess it might come down to cost in the end, based on the cement fibre at the lowest and working up from there.

All the best and thanks for your time and info Tim

T i m

[T i m]

Agent shows this reply on the end of another thread but I'll answer here anyway.

I quite like the sound of rain, especially when I'm trying to get to sleep (tinnitus sufferer) but I try not to do that when using the Myford. ;-)

LOL. We have a poly carbonate lean_to roof that has a similar effect and is normally our 'audible rain indicator'. ;-)

I bet!

So, if I can get some sort of resolution to the ridge question, maybe corrugated cement fibre would be a cheap / quiet / cool (as in temp ) easy_to_source solution and potentially less likely to attract any attention (as it's what's on there already).

I will just have to design in (and will have more space for with the increased pitch) some form of roof lining (the walls are lined with ply and insulating material already).

All the best

T i m

[Tim Lamb]

In message , T i m writes

November 2006 AS35 80mm composite sheeting cost £23.78/m

I also bought some AS35 40mm seconds at £7.73/m. Seconds are slightly damaged: dented/overlong etc. They are exempt from LPC approval so may not be a good idea for a domestic installation. I used a metal cutting circular saw to cut them but there may be other ways.

For a ridge, you will need internal and external folded section at around £5.00/m. Ridge fillers at £0.75ea. Also 90 deg. barge at a similar price. Fixings are not exorbitant.

Delivery might be an issue as these usually arrive on an artic fitted with a Moffet Mountie fork truck. Delivery to Herts. was £150.

I guess you have 3" cement fibre in self colour. I found delivery times on painted *big 6* sheets had reached 3 months, recently.

regards

[The Natural Philosopher]

You haven't lived through a tin roof in a tropical thunderstorm then.

[Mary Fisher]

Ah, thank you - that's the nicest thing I've heard all day.

Mind you, it is fairly early in the day - for me ...

One at a time is good.

Mary

[meow2222]

Lol. Seriously though, its nothing like that bad. In fact it isnt bad at all. The sound gives early warning of rain, which is handy to enable the quick dash to the house before it starts raining properly.

TNP wrote:

no, but I never found them a problem for British weather. Only in a storm does it start getting noisy.

OTOH if the OP can get fibre cement for less, I would. No condensation problem, less heat loss, less heat gain, rustproof forever, no contest really.

NT

[T i m]

Ouch .. :-(

That is slightly better (considering it is already insulated etc) but still not cheap if you are d-i-y'ing (ie, not having to pay labour).

I guess if that was say a sheet of polycarb or cement fibre you could easily cut off the excess or lose a damaged corner somewhere where it didn't matter. I seems this AS35 is quite a 'engineering' solution in how the joints are made / sealed etc.

Even for something like a fully detached workshop Tim?

Ok ..

That's another couple of hundred quid?

So would be the same for me (Herts) as it's probably per load rather than value?

Yep ;-) While we are on the subject, would you know what other colours are available please?

Oh, ok, well in the real world I have a lot of work to do before I get to that stage so may not be a problem etc. re the painted sheets Tim, is this something that would need re-doing in time?

All the best and thanks again Tim.

T i m

[T i m]

;-)

Nurse came round a bit earlier today then?

Motorbike, light or tile? If it's the latter the former will get wet till I do the lot?

All the best ..

T i m

[T i m]

Cheers, that should save me a few quid (you are very generous) ;-)

Hmm, I do get *some* (I have to protect lathes and other kit to stop them rusting).

Oh, so CF is quite good then?

No 'hot tin roof' ;-)

True ..

Hmm. I hadn't really considered it to be a 'good' but 'cheap' solution (as provided by these pre-fab garage Co's to keep the price down etc) but maybe I was mistaken?

All the best ..

T i m