I have had the small (6x8) HFGH since November 2005 and so far see no holes, brittleness, deterioration or discoloration of the panels ... they look like new. I'm sorry to read yours are not holding up as well and hope that someone has a more helpful response for you.

Perhaps it would help if you could describe the problem: Is it inside, outside, or both? Is it worse in any particular area or on some panels? To your knowledge, have the panels have been exposed to any chemicals?

I've only had mine a little over a year but haven't seen any detioration. Any spraying that may have caused this?

James, I remember last time you posted [in this thread,](http://forums2.gardenweb.com/(http%3A/forums2.gardenweb.com/forums/load/strucs/msg03230435933.html) you said the south panels were deteriorating. So, now the west side too?

I tried Googling for other reports of polycarbonate panel deterioration or damage, but the only thing I found was the same problem mentioned by googoo_dahl in the previous thread about exposure to mosquito repellant.

I have seen ammonia included among the chemicals that can attack polycarbonate...since this is on two sides now, I wonder if it could it have been caused by some type of ammonia cleaner used on the greenhouse?

I also wonder if Harbor Freight might have any info...if they've any previous reports of this problem.

My 6X8 HFGH will soon be 2 years old and the panels are like brand new. I've washed them with Palmolive dish soap and hosed them off. I don't use anything harsh on them. Have you sprayed anything that area? How about a neighbor?

I put my HFGH up in the Spring of 2007. In 2009 I noticed that there were small holes in the roof panels. Notice that I said roof panels. All of the roof panels have many holes in them and they are very brittle. Several have cracked.

What's odd to me is that all of the wall panels show no sign of problems. They are still clear, no holes and are not cracking.

To me, it's apparent that the ceiling batch were cut from a different batch that the walls were cut from. The ceiling batch is obviously defective.

I've never complained to HF, but I really thing that certain supplies of polycarbonate panels really are defective.

Now, I'm debating whether to find some other material to replace them with or order another HFGH just for the panels.

Joe

Here is a link that might be useful: My HFGH

Joe, in case you didn't see it, Laserfan posted this information recently about a 4mm polycarbonate product now available from Tek Supply:

"I notice today that teksupply is carrying 4mm in the (much higher quality with UV protection) PALRAM polycarb. Expensive as all get-out, but here you go. If you look at this page, be sure to download both of the pdf files there as they contain excellent information about both the product and it's application/handling/installation etc. that you will find valuable I'm sure.

Link to Teksuppy 4mm page:

laserfan"

If we eventually do have to replace our panels, I'll at least give a more expensive option like this some careful thought, since I figure it will be a major ordeal to replace the panels in mine (I'll have to empty out the greenhouse, which remains stuffed year round.) I don't want to spend big bucks...but I'd rather not replace the panels very often, either, and I now know the HF panels may well have a limited life span in my climate.
Sheri

OK, I did it. I've order the roof replacement panels from HF. The lady said that they would arrive in 5-6 business days.

I double checked the prices and find it hard to believe that they are so inexpensive compared to Charlies. His shipping was almost as much as the HF order.

I'll see what happens to these and keep you all posted. I will probably get what I paid for, but if I can get a few years out of them, it will be worth it.

See my order confirmation below.

Joe

Thank You for Ordering from Harbor Freight Tools

Here is your Order Confirmation
Order ID:xxxxxxxxxxxxx
Order Date:2011-01-04 07:18:40.453
***Order Summary***
4 13361-0ZZA 93358 ROOF WINDOW PANEL 1'11 X @ $9.72
8 13366-0ZZA 93358 ROOF PANEL 1'11 X5'9 @ $9.41
Subtotal: 114.16
Tax Rate: 0.08
Tax Total: 10.17
Shipping: 12.99
Handling: 0.00
TOTAL: $137.32