What type of roof to replace a rotten fibre cement dairy shed roof?

[Chippy]

I have a 1200 meter squared roof to replace. I’ve visited Holland a lot and all I see is composite roof with insulation under it. Is this to keep it cool in summer and warmer in winter? Why don’t we use this type of roof over here? Is it just price? Do I use fibre cement again or composite but with non drip stuff on it or small amount of insulation?

 

[Blue.]

I have a 1200 meter squared roof to replace. I’ve visited Holland a lot and all I see is composite roof with insulation under it. Is this to keep it cool in summer and warmer in winter? Why don’t we use this type of roof over here? Is it just price? Do I use fibre cement again or composite but with non drip stuff on it or small amount of insulation?

Yes cooler in summer,warmer in winter.

All down to price.

You could underclad the purlins and insulate under fibre cement sheets,probably still work out cheaper than composite panels.

 

[Chippy]

Also, should I put lots of sky lights in and allow shed to get too warm in summer or none and use LED’s which will be going in anyway?

 

[dannewhouse]

Also, should I put lots of sky lights in and allow shed to get too warm in summer or none and use LED’s which will be going in anyway?

Will you set them up for 16 hours of daylight etc
If so wouldn't bother with them, what's the first sheet blown out in an old roof?

What about a light ridge?
What LEDs are you going for?

 

[Chippy]

Yeh was going to set them up for the usual 18 hours of daylight and 6 of darkness. LED’s I’m using are ones YESSS electric sell. I’ve got light ridge in new part of shed and it’s good but at £1000/bay it’s a bit dear really. LED far cheaper and I produce my own electric so cost of running isn’t an issue. I read more and more articles about heat stress so surely it’s best to have no sky lights isn’t it?

 

[dannewhouse]

Yeh was going to set them up for the usual 18 hours of daylight and 6 of darkness. LED’s I’m using are ones YESSS electric sell. I’ve got light ridge in new part of shed and it’s good but at £1000/bay it’s a bit dear really. LED far cheaper and I produce my own electric so cost of running isn’t an issue. I read more and more articles about heat stress so surely it’s best to have no sky lights isn’t it?

Wouldn't bother with roof lights then, or a light ridge at that price!
How much is a normal vented ridge?
I've been looking at led floodlights plenty of them but they vary all over in price. Problem is you need plenty so your not in shadow all time, a few powerfull ones is no good

 

[Chippy]

I got a price off a company to supply and fit lights in my 200 cow shed to provide 200 lux and it was £15,000 ?
I can buy the equivalent off YESSS electric for £3000 and fit with my electrician and telehandler ?

 

[dannewhouse]

200 lux X (square m of shed) (1500m2??) = Lumen
300000 lm
28000 = £187 biggest unit on list
300,000 / 28000 = 11 units
11 X 187 = £2057
50w is 3500lm floodlight, cheapo at £15?
300,000 / 3500 = 86 units
86 X 15 = £1290
Seems a compromise in between numbers would be best but few big units end up shadowing everywhere.

 

[Headless chicken]

@Bald Rick

 

[Bald Rick]

Also, should I put lots of sky lights in and allow shed to get too warm in summer or none and use LED’s which will be going in anyway?

It is our experience that NO roof lights are the best way forward as the shed is degrees cooler is summer and no different in winter. As a minimum I would have an open protected ridge or you could consider opening the sheets by 5mm or so for rapid venting

Interestingly we have just been testing our lights and the High Pressure Sodium’s are putting out a minimum of 230 lux anywhere we measured but the High Barn LEDs were only over 200 lux directly under the lamps but quickly faded although to our eyes the LEDs were much brighter.

Insulated sheets are expensive and as we are not in an area where we have long, cold winters we discounted them although it was a strong possibility for the calf unit.

 

[335d]

What about the new sheets that let light in, but block heat. apparently used a lot in mainland Europe.

Home - Greenhill Systems

www.greenhillsystems.co.uk

 

[Forever Fendt]

the lowest price composite panels we have seen have been about £15 sq meter new and big six less than £6 so a big difference even on a small project