Alpha system roof

[747sheltie]

We just picked up our 2014 ST26RB this week. It is my understanding Crossroads is now universally using the alpha systems roof in all models, as advised by the dealer.

Upon inspecting and cleaning the roof I noticed it to be quite soft and spongy, to such a degree I sought out placing my weight directly on the roof trusses where possible, the outlines of which were slightly visible under the roof membrane. It is so spongy I thought that maybe one should not be on the roof to clean it, although the dealer did not advise such when we discussed appropriate cleaning practices.

Does anyone have any feedback on this issue? I certainly do not want to have concerns when attempting to clean the roof. I was really surprised as to how spongy this type of roofing system is, unlike roof systems used in the past by manufactures. Maybe walking on it is not a problem?

Thanks,
Greg

[cw3jason]

Just stay on the trusses and it will be fine to clean, you can also put down some shoring if you are really concerned

[JBE-dad]

I got on the roof of my Sunset TT last week for the first time and had the same spongy feeling. Was not comfortable at all being on top of the roof.

[Lloyd]

What is this (Alpha system roof)? I've never heard of it.

[747sheltie]

I don't weigh that much, and am concerned about how it felt. I guess what would provide some sense of comfort is what the manufacture says is permissible. Are you aware of what their response or direction is?

I just joined the forum, so maybe this issue has been discussed previously and I am not aware of it.

[747sheltie]

Apparently it is roof system now being used in construction. I will be doing more research on it, but I believe it is the latest generation of rubber type roofs. It is so soft and spongy, it does not make you feel secure about not doing harm to the membrane (i.e. causing a breech and therefore a potential leak opportunity).

[cw3jason]

The Alpha system roof is just the membrane used, it is manufactured by Alpha Systems LLC. The Alpha-Ply membrane blends the flexibility of an EPDM membrane with the durability of a plastic membrane to provide the next generation of RV roofing. The softness of the roof is cause by the light weight materials used in the construction of the roof frame and decking. I will have to look it up, but I believe it is a aluminum truss roof with 3/8 marine grade plywood decking, hence the flex. This helps keep the weight down, but still adds plenty of strength for the roof. Again this roof is not meant to be walked on accept to do routine maintenance and inspections and I would recommend staying on the trusses

[mark5w]

Direct from Alpha Systems LLC.

To help OEMs achieve their goal of reducing weight in their units, Alpha developed a roofing membrane which is practically half the weight of EPDM. The Alpha-Ply membrane blends the flexibility of an EPDM membrane with the durability of a plastic membrane to provide the next generation of RV roofing.

http://www.alphasystemsinc.com/Product/ProductList/1

Link to their website.

Sounds like it's a membrane system, not a membrane and truss system.

[Lloyd]

Thanks for the leg work Mark. That's what I was asking.

[747sheltie]

Thanks for the quick info Jason and Mark. The link to the website was a big help.

Greg

[harley]

You may want to take the 4 scrwes off one of the roof vents(inside) and take down the plastic inside cover and look to see how thin the luan "plywood" is . It is not 3/8 marine. It looks like 3/16 only .
I was also told to walk on trusses and only for roof maintenance. I was also refused a ladder option cause they don't want people up there.

[cw3jason]

according to the specs, it is 3/8 plywood and steel trusses

[Lloyd]

Originally Posted by cw3jason

according to the specs, it is 3/8 plywood and steel trusses

I think I would verify that info with CR before I took it to the bank.
One thing I find unbelievable is --steel roof trusses. I don't know if I believe 3/8 plywood either. They use to be known for using 1/4 material.
I know, the spec sheet states what cw3jason posted, but I'm skeptical.

[747sheltie]

Thanks for the info. I will pull the vent to get a good visual on the wood underlayment. Whatever thickness it is, if you have been on your roof you will feel the soft and spongy response as you maneuver your weight to walk around. I must say I was surprised. As long as it performs well is the key. I am sure CR has done their homework.

[LeBo]

Here's some info on the Alpha roof system. http://www.alphasystemsinc.com/ourstory