Rubber roofing ?

[Astrokev]

Hi All

Still thinking of designs for my ROR observatory. I've seen a few builds were rubber sheeting has been used instead of more traditional felt.

I think rubber is more expensive than felt, but there are upsides which I presume in the long run offset the cost.

I'd be interested to hear from those that have used rubber - please can you recommend suppliers? Is thickness important? Is fitting it easy? How does it compare to felt regarding weight?

Many thanks

Kevin

[Gina]

I got mine online from Rubber4Roofs. It's lighter than felt and certainly far easier to fit. No joins needed as it comes nice and wide. It doesn't split or crack like felt tends to. It's reckoned to have a life exceeding 50 years. Not that it's been going long enough to proove that I've been very pleased with it. I was dreading putting felt on but the rubber stuff was a doddle - just apply the adhesive to the wood with a radiator paint roller and roll the rubber on. You can smooth it down with your hands - it's got a smooth surface - or ues a roller. I recommend it wholeheartedly Yes, it costs more than cheap felt but I think it's worth it.

[Islander]

Yep, Rubber4Roofs - very helpful people and they'll cut the sheet to any size you want.

It's a doddle to fit - far easier than torch on felt and it'll outlast it too.

[r3i]

I would second everything that Gina said: Having covered the warm room roof and just finished the rolling section on my observatory with EDPM, I would not hesitate to recommend it. It was just so easy to install and you get a very neat and seamless finish with little effort, I also used a radiator paint roller to apply the adhesive.

And yes I also got mine from Rubber4Roofs. The only downside is that it is considerably more expensive than traditional felt, but the benefits far outweigh the additional cost IMHO.

[Carbon Brush]

Yes what Gina said.

In my case I bought pond liner rubber. Easy to get locally in the size I wanted.

A bit of effort gluing and waiting for glue to set. But that was partly down to my roof design.

5 years on, no sign of problem. Not even on the flap that hinges up on one gable end at every opening.

[r3i]

5 years on, no sign of problem. Not even on the flap that hinges up on one gable end at every opening.

Good to hear a positive long term report on how this material is standing up to the great British weather.

[Astrokev]

Thanjks guys. Rubber4Roofs it is then.

Now I need to decide whether to have a pent roof over the main obs, or a flat roof that will roll over a warm room.

[Carbon Brush]

I have a pent roof. It needed quite a bit of extra strengthening to prevent sag.

A 'normal' shed roof is supported on 4 sides and it doesn't matter if there is a bit of sag.

The roll off is supported 2 sides only.

If a flat or pent roll off sags, then it jams, or you have to leave a big clearance between wall and roof, or fix extra castors/sliders to provide more support. It can be messy.

If building again, I would probably go for a shallow gable to improve rigidity.

[Gina]

I had thought of using a pent roof for both warm room and roll off roof but I eventually went for a shallow gable. You can get rigidity with lightness that way.

[Astrokev]

Actually, I realise I made a mistake and was getting me roof types mixed up! I was meaning a gable roof and not a pent, although the latter could be easier to make in some respects. I'm sure it would be possible to brace it so that it doesn't sag. Mmm, must give this some more thought....

[r3i]

Actually, I realise I made a mistake and was getting me roof types mixed up! I was meaning a gable roof and not a pent, although the latter could be easier to make in some respects. I'm sure it would be possible to brace it so that it doesn't sag. Mmm, must give this some more thought....

I did think about pent roofs for both the warm room and rollling roof, but eventually decided on a pitched roof for the rolling roof - not really sure why, it just felt more aesthetically satisfying

[Gina]

You can make a pitched roof stiffer for a given weight.

[Bizibilder]

A swift question about these rubber materials if I may? - If you were to glue the rubber sheet to, say, the outside of the wall of a wooden shed, could you simply cut the rubber sheet along the top of the wall or do you have to "wrap it over" and glue it before cutting? (Hope what I am suggesting is clear). Does the "edge" of the rubber stay stuck or would it slowly peel away?

[Carbon Brush]

I used a sheet large enough to cover the entire roof, sides and wrap under.

No joins meaning no risk of leaks.

All of the rubber was glued in place. No nails, etc.

The only exception was some staples throuigh the wrapped under (dry) parts.

Should repairs be needed, there are pond liner repair kits available.

Hope this is useful. David.

[Bizibilder]

Thanks - that makes sense. Unlike Roofing felt, which can become "bulky" when wrapping round corners - if you crease it it may tear - the rubber will easily fold over a 90° angled corner?

[Astrokev]

Thanks - that makes sense. Unlike Roofing felt, which can become "bulky" when wrapping round corners - if you crease it it may tear - the rubber will easily fold over a 90° angled corner?

Good question. I was also wondering about this.

[r3i]

A swift question about these rubber materials if I may? - If you were to glue the rubber sheet to, say, the outside of the wall of a wooden shed, could you simply cut the rubber sheet along the top of the wall or do you have to "wrap it over" and glue it before cutting? (Hope what I am suggesting is clear). Does the "edge" of the rubber stay stuck or would it slowly peel away?

If I recall, there is a PDF on the Rubber4Roofs site that explains how to install, and they send you a hard copy when you purchase from them. There's also an installation video. But basically they suggest that you can either tack the wrapped edge down with clout nails or fit a wodden batten.

And yes it's very easy to fold over as required.

[Gina]

You can fold the corners neatly like packing a parcel, the rubber is not too thick and it retains it's flexibility, doesn't harden with age etc. (so they say - not had mine long enough yet to know). However, I can say that gluing the rubber flat onto the woodwork of the obsy where the rubber is under stress to fold back, doesn't work. It DOES come unstuck. It needs to be fastened down with either battens or clout nails. Round the edges of the roof, I wrapped the rubber underneath and fastened it with clout nails. That produces a nice tidy job.