New roof - Fibre cement roofing - Anyone used??

todayisagreatday

Hi

We've just had positive feedback from pre planning advice and will submit a full application very shortly.

For the roof and the top half of the house (it will be extended up from a bungalow to one and half storey) we want a corrugated steel look, we initially considered Tata Colourcoat Urban and Vieo but we're a bit put off in terms of a few unfavourable reviews on the weathering of this and cost. We will also have 9 skylight windows too. We have started to look at alternatives that give us the corrugated look. As I said before it will only be the roof and top half of the house as the test will be render and it will be quite modern in appearance.

We have seen Cembrit, here is an example though we definitely don't want it for all of the house as it can look a bit farm building like but we are very rural, adjacent to the canal so it will actually be quite in keeping with the area. I'm waiting for samples of colours.


https://www.cembrit.co.uk/projects/?project=39876

We have also seen Marley Eternit Profile 6 which is similar too. I'm just wondering if anyone has used this or any roofers who have an opinion. I know it's previously been associated with asbestos historically and the look won't be for everyone but any advice or opinion would be great.

Many thanks

EachPenny

todayisagreatday wrote: »

I'm just wondering if anyone has used this or any roofers who have an opinion. I know it's previously been associated with asbestos historically and the look won't be for everyone but any advice or opinion would be great.

As a general comment, when it comes to appearance and colour stability I would say a plastic coating on steel is more likely to last than a coloured cement product. Coloured cement products tend to fade and discolour quite easily, and also support the growth of organic material. This is great if you ultimately want a 'weathered' natural look, not so great if you want it to look uniformly clean.

The other comment I'd make is that steel sheeting is usually available in longer lengths than cement-based products. You need to investigate maximum sheet lengths and compare that to your requirements. Cement-based roofing products look untidy where you have overlapped joins - which would be necessary if the cover length on your roof exceeds the maximum available sheet length. If you can cover the roof with a single length of steel sheeting you will have a cleaner, neater look.

You also need to look at the availability of trims, especially if you are covering walls. Cement-based products may have a limited range of trims (e.g. covering external corners) whereas with steel the supplier can often manufacture any shape trim you need. Your final choice might depend on the availability of these 'extras' rather than the bulk of the sheeting.

Personally I've used a lot of plastisol covered steel sheeting, much of it as 'seconds' from an agricultural supplier. After 10+ years it is still looking as good as when it was installed.

If you are concerned about the quality of any product, ask your supplier if there are any installations in the local area you could go and view.

todayisagreatday

EachPenny wrote: »

As a general comment, when it comes to appearance and colour stability I would say a plastic coating on steel is more likely to last than a coloured cement product. Coloured cement products tend to fade and discolour quite easily, and also support the growth of organic material. This is great if you ultimately want a 'weathered' natural look, not so great if you want it to look uniformly clean.

The other comment I'd make is that steel sheeting is usually available in longer lengths than cement-based products. You need to investigate maximum sheet lengths and compare that to your requirements. Cement-based roofing products look untidy where you have overlapped joins - which would be necessary if the cover length on your roof exceeds the maximum available sheet length. If you can cover the roof with a single length of steel sheeting you will have a cleaner, neater look.

You also need to look at the availability of trims, especially if you are covering walls. Cement-based products may have a limited range of trims (e.g. covering external corners) whereas with steel the supplier can often manufacture any shape trim you need. Your final choice might depend on the availability of these 'extras' rather than the bulk of the sheeting.

Personally I've used a lot of plastisol covered steel sheeting, much of it as 'seconds' from an agricultural supplier. After 10+ years it is still looking as good as when it was installed.

If you are concerned about the quality of any product, ask your supplier if there are any installations in the local area you could go and view.

Thanks for this detailed reply. I have asked the question about installations in our area for both Cembrit and Marley Eternit. I've also sent off for some samples of plastisol corrugated sheeting from Rhino in the Midlands which do a range of cement fibre boards and steel sheets, we may have to visit and have a chat.

One point I'd read on another forum mentioned from someone who had build two large framed buildings was that 20years on the sheeting started to peel its plastisol coating and there is no real way to cure it as any paint coating would be on top of the plastisol that has not come off yet--so it would peel later.

I guess with cement board corrosion is never an issue, but I do need to look into the fading I guess finding out long term how both these materials have weathered and stood the test is going to be difficult.

We need to consider cost, warmth/insulation, maintenance, cost of installation and also whether one is better for the installation of skylights. We don't have a particular preference on material as long as it has the corrugated appearance, it's just trying to weigh up pros and cons of both and I'm feeling completely overwhelmed!!

EachPenny

todayisagreatday wrote: »

One point I'd read on another forum mentioned from someone who had build two large framed buildings was that 20years on the sheeting started to peel its plastisol coating and there is no real way to cure it as any paint coating would be on top of the plastisol that has not come off yet--so it would peel later.

Always a risk, but can be minimised with great care and attention during installation. (e.g. clear up any drill swarf rather than leaving it, or worse - treading it in to the coating).

You really need to look at the cost per square metre for the different materials and their expected lifespan. Steel is relatively low cost, you might consider it reasonable to write off the cost over 20 years (i.e. expect to replace it at that time) and find the cost is comparable to other options. You might also want to look at the feasibility of ordering some spare material now to keep in storage to carry out any future repairs.

todayisagreatday wrote: »

...also whether one is better for the installation of skylights.

This is where my previous comment about the availability of trims comes in. You'd need a material which you can get suitable components (off the shelf or made-up) to accommodate the windows. You can probably achieve anything with some leadwork, but you'd need to factor in the cost and effect on appearance. Steel certainly lends itself to adaptability more than cement-based roofing.

todayisagreatday

EachPenny wrote: »

Always a risk, but can be minimised with great care and attention during installation. (e.g. clear up any drill swarf rather than leaving it, or worse - treading it in to the coating).

You really need to look at the cost per square metre for the different materials and their expected lifespan. Steel is relatively low cost, you might consider it reasonable to write off the cost over 20 years (i.e. expect to replace it at that time) and find the cost is comparable to other options. You might also want to look at the feasibility of ordering some spare material now to keep in storage to carry out any future repairs.

This is where my previous comment about the availability of trims comes in. You'd need a material which you can get suitable components (off the shelf or made-up) to accommodate the windows. You can probably achieve anything with some leadwork, but you'd need to factor in the cost and effect on appearance. Steel certainly lends itself to adaptability more than cement-based roofing.

Marley Eternit have confirmed Velux do flashing kits for the profile 6, but I've contacted https://www.roofingsheetsbyrhino.com which do a range of products and hopefully will visit and get some information on m2 cost too