Solexx to replace polycarbonate on my Harbor Freight GH?

Do-it-yourself projects such as greenhouse or shadehouse builds and related topics.
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mudhouse
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Solexx to replace polycarbonate on my Harbor Freight GH?

Post by mudhouse »

My four year old 10x12 Harbor Freight greenhouse has served me well, but the clear 4mm thick Harbor Freight twinwall polycarbonate panels have finally deteriorated in the harsh sun of southern New Mexico (yellow, brittle, and holes.) I could order new panels from Harbor Freight, but have ruled that out, since I don't believe their panels truly have the UV protection mentioned in their ads, and I'd rather not do this again in three or four years. I'll either have to buy new 4mm twinwall polycarbonate elsewhere (very expensive with crating/shipping) or try using Solexx.

The shipping cost on Solexx isn't as bad since it's more flexible and can be shipped by the roll. The 3.5mm thickness should work fine in the aluminum frame of my Harbor Freight greenhouse, but I have some concerns about moving to a translucent white material, instead of the clear polycarbonate I'm used to.

I do use a 60% Aluminet shadecloth drape on my rooftop now, year round, and I have an interior 30% drape I use during the worst part of the summer (in addition to the 60% on the roof exterior.) So, I'm probably worrying over nothing, I guess. The more diffused light of the Solexx might allow me to do away with some (or all?) of my Aluminet shadecloth, but this is the hardest thing for me to predict.

Have any of you used Solexx for a greenhouse covering, and were you happy with the amount of light transmitted, for our light-loving cacti and succulents? Thanks for any of your thoughts. (I just checked my greenhouse roof under the shadecloth, and found it's in much worse shape than I'd thought, so I'm looking to order something, pronto.)
Sheri
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cactushobbyman
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Post by cactushobbyman »

I built my greenhouse with 8mm twin wall polycarbonate. My area sees 110 degree summers. I bought my polycarbonate in 4X10 sheets to match my building requirements. I too use shade cloths during the summer. I bought the poly from growers supply.com. Or Farm Tek. Both will link to the poly. Look at my post on this page to see the panels. What I bought is UV protected, so you have to install it correctly. If you get hail, they may require thicker poly.
mudhouse
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Post by mudhouse »

Cactushobbyman, thanks very much. Your greenhouse is quite beautiful, what quality woodworking! Redwood just seems to look great with green plants. I have also considered adding a light fixture, as you have.

We splurged on redwood slats for our benches, and I used redwood stain on all the other (cheaper) interior wood. Here’s a pic of the benches during the build:Image

And after a few plants were stuffed in:
Image

We also built a potting bench with small sink in the greenhouse, and I did a mosaic surface. I know I lost some plant space by doing this, but I really enjoy it. Took this pic soon after finishing it. I am not going to show you what it looks like today (covered with dirt, pots, and a big mess!) Image

This is our first greenhouse, so we didn’t have the courage to build from scratch as you did. We think we could build our own now (your nice structure would be a great inspiration.) But the current Harbor Freight frame, electrical, benches etc are still fine; it’s only the inexpensive (made in China) polycarbonate panels that have given up the ghost.

It's tough for me to upgrade to 6mm or 8mm polycarbonate, from the 4mm thick kit panels, because of Harbor Freight’s aluminum framing at the roof peak. Anything thicker than 4mm will not slide into the slot at the roof ridge. We have discussed ways to defeat this, but staying with a thinner panel material is easier. So, that led me to consider Solexx. It is quite obviously much less beautiful than clear twinwall poly, but it has a better R factor even though it’s only 3.5mm thick.

I’m also swayed by price. Solexx does not have to be crated and shipped by freight, so it’s much cheaper to order. I can buy fourteen 4’x8’ sheets of 6mm twinwall polycarbonate to recover my 10x12 greenhouse for $1023 (yikes) or I can buy 3.5mm Solexx for $672. It’s hard to give up the looks of clear twinwall poly. It’s also hard to find many posts on gardening forums from folks who have used Solexx!

The Harbor Freight has a bad reputation for being flimsy in wind, and the manual is difficult. I did a little blog with some tips to help folks build and reinforce the structure for strength. I’ll update soon blog with another section on replacing the kit panels. Sure wish replacement panels weren't so expensive. :shock:
http://hfgh10x12.blogspot.com/2007/08/t ... nk-it.html
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CoronaCactus
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Post by CoronaCactus »

In my opinion, the whiteout type panels or film is much more effective on large structures. From all the nurseries and growers I've visited I cant think of a single place using the whiteout on a structure smaller than 40' x 80'. On small structures it seems too shaded. Maybe it's an illusion? I've never metered it.

However, if you're using 60% and 30% it may equal out and you could eliminate one of those. Personally I find thats too much shade, is NM that much more sunny than CA? I find that 50% under clear polyfilm is the most shade I'm willing to use. I'm even thinking of going down to 40%.

I think Harriet used solexx panels on her shadehouse roof?
mudhouse
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Post by mudhouse »

Thank you for weighing in, Darryl. I find myself quickly over my pay grade on this sun subject. In an attempt to consider your question about the difference in sun intensity between your part of CA and my part of NM, I grabbed this sun intensity map from this site http://www.nrel.gov/gis/solar.html for what it's worth. My location is the black X in the lower part of New Mexico:

Image

Also my greenhouse has a southern exposure to the longer side, with absolutely no shade, and gets smacked by the full west sun in the evening too (brutal here.)

I initially ordered the 30% Aluminet when greenhouse was new, since I assured my husband "succulents need very bright light" and found it was not nearly enough. I thought I'd be able to remove the 60% drape from the roof during parts of the year, but as the years went by, found my plants were fine with leaving it in place. Even with this, I have a lot of succulents (mostly non-cacti) that only do well on the north side of the little GH, on a lower shelf, in the darkest shade. Go figure. It sure has been a learning experience for me.

But your comments echo my nagging worry...what if the translucent white, in spite of what my brain is telling me, filters out too much light? My reading shows Solexx transmits 70-75% light. Doing just the roof in Solexx is an option, and would cost about $250. At least then I'd have a ten year hail-resistant roof, and I could even use the (miserable) Harbor Freight replacement panels on the walls, figuring I'd need to rotate them out again in 3-4 years. Replacing the roof is the bad part, since I keep plants in there year round.

Thanks again for your input. Maybe there is a reason I can't find much info on hobby greenhouse owners using Solexx on small buildings...? Hmmm.
Sheri
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CoronaCactus
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Post by CoronaCactus »

Ok according to that map, I'm probably closer to 6.0. How much of a difference that really is...i have no idea. Our GHs are lengthwise north/south and also get full sun exposure for as long as its shinning. In winter they get a break around 4:30pm from some trees.

I think just the roof might be a good plan. Just doing a quick search it's hard to find 4mm polycarb, the majority seems to be 6 to 10mm with 8mm being most popular. I bet Harbor Feight did that on purpose! 8)
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Harriet
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Post by Harriet »

I opted to skip the Solexx because of the way it looks (white/cloudy), and I ended up using a single walled clear poly carbonate for the roof of my structure. I went with clear as I would rather deal with shading too much sun, than not getting enough to begin with. Also, I am not too worried about heat loss in the short time I will have to use a heater in our winter.

We are in the process of enclosing the whole shade house and will be using a double walled clear poly carbonate for the side panels. The stiffer double walls will just work better for what we want to do to it. And I like to see the plants from a distance, you can't do that with Solexx.

Those of you on the west side of the country have much better sources for poly carbonate than I do, I have had a hard time finding what I need locally. And shipping large panels is expensive!

Keep us posted on your progress, I like to see how other people do what they do!
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Harriet
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Post by Harriet »

BTW, the potting sink is really cool! And your plants look great too.
It’s not the fall that kills you; it’s the sudden stop at the end.
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mudhouse
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Post by mudhouse »

Thanks Harriet. I have the same thoughts regarding the white color and loss of viewing my plants. Our greenhouse is very visible to many neighbors, and I have been dreading subjecting them all to a view of a "plastic white greenhouse." I have searched high and low for some polycarbonate supplier close to me (or anywhere in my state) but have come up empty, so I can't avoid those astounding crating and shipping fees either.

So far, Farmtek is the only site I've found offering 4mm twinwall polycarbonate. I reconsidered some of my roof design (removing some vent windows I never use anyway) and now have these figures to choose from, for redoing my roof:

Farmtek 4mm twinwall polycarbonate, about $410
Solexx 3.5mm, about $350
Harbor Freight (not really UV coated) 4mm twinwall poly, $135

Frugality won out, this time. I just ordered 12 roof panels from Harbor Freight, shipping tomorrow from California by Fedex. Although I know they'll likely need replacing in (maybe 3?) years, the low cost pulled me in, and will buy us some time to do more research. (Nothing like kicking the can down the road, eh?) At least I won't have to refigure my shadecloth set up. I have no idea how they can ship twelve (roughly) 2' by 6' twinwall poly panels for only $12.99, with no crating fee, but they do. I caved.

I will also probably order more of the HF panels to replace the worst of the yellowed wall panels, too. It will look very nice for a few more years (my neighbors will thank me.)

Maybe I'll learn more about Solexx in the next few years, before I have to replace panels again. Maybe I'll win the lottery, and build a bigger greenhouse, with nice juicy 8mm poly twinwall, all the way! :D

Thanks again for everyone's comments to help me think this through. Much appreciated!
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CoronaCactus
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Post by CoronaCactus »

Wow, that's quite the price difference!

Be sure to take some pics so we can see it too!
apfire
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Post by apfire »

The local HD here and Lowes both sell polycarbonate panels. Here in Florida they are suggesting they be used for hurricane shutters. I purchased my panels from a building supply place. I have to admit there are quite a few plastic dealers here due to the local tourist attractions.
I am just looking for the defining statement to put here. Follow this link to see my other cacti.
http://s290.photobucket.com/user/apfire ... cti%202013, 2014 http://s290.photobucket.com/user/apfire ... New%20Year
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Post by cactushobbyman »

Your interior looks great. I went plain knowing I am very rough on things. I could have bought my poly local through Tap Plastic. The difference, Farm Tek offered 4x10 planels. Freight was high, cost was high, but I hope it will last a long time. At the price of HF replacement, you can keep replacing for a while until your research is complete. I also looked at Solex. Didn't like the white. Great job on the sink, plants looks great.
mudhouse
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Post by mudhouse »

I will take pics for sure, Darryl! I want to document the deteriorated HF panels for my blog, to give other folks in sunny climates a heads up about this potential and unfortunate drawback. (Harbor Freight still rules, though, for ultra cheapskates like me.)

Apfire, lucky you to have sources for plastics locally. I never thought about that in regard to your local Florida tourist industries. Around here, the types of dealers supported by local tourists mostly sell Mexican pottery! :lol:

Cactushobbyman, I showed my husband pics of your greenhouse for future inspiration. I am rough on stuff too, but had fun trying the sink countertop for grins. The edge tiles are now badly scratched from dragging pots and gravel across the work surface, but even in the normal disastrous state, I can still see the pattern through the dirt (mostly.)

I'm sort of glad you folks don't love the white color of the Solexx; makes me feel better about avoiding that choice for now. Being practical is good, but I guess there's nothing wrong with putting a value on being happy with the look of our structures.
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Post by daiv »

Great post. This section is one of my favorites of the forum. Your greenhouse looks fantastic. From the looks of it, you could buy new Harbor freight panels a few times for one Solexx or Farmtek. I probably would end up doing that too.

You may have said it somewhere in the post, but how long did the HF panels last you?
All Cacti are succulents, but not all succulents are Cacti
mudhouse
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Post by mudhouse »

Mine lasted about four years, but I should have replaced them sooner, as the photos below show. I thought my heavy shadecloth was protecting the roof somewhat, and that I would be able to monitor roof panel damage from the inside of the greenhouse. But, the damage was not apparent, since the small holes are only in the outside layer of the twinwall. When I finally got around to removing the shadecloth from the roof a few days ago, to really check the outer layer of the twinwall poly, I found the entire roof was swiss-cheesed with 1/4" sized holes. Almost fell off the ladder!
Image

I have two panels on the south side that are not protected by shadecloth at all. The dots on the ugly yellowed panel are my patches with clear duct tape (classy huh) to cover the holes that started showing up last year. (The adjacent silvery panel is one of four Aluminet screens that I put in place during the summer.)
Image

I think Harbor Freight came out with the 10x12 size greenhouse in 2006. I noticed the first posts about panel problems in May of 2008. One HF owner in south Texas had severe roof panel failure after only one year, but he had never used any shadecloth. (Shadecloth seems to slow down the deterioration.) Some HF owners in less intense climates are still posting that their panels are fine, after four or five years. One HF owner only had to replace his roof; his side panels didn't deteriorate, so maybe this problem is compounded by variations in manufacturing quality. The entire HF greenhouse is made in China (thus the incredibly low price.) So, panel life seems to vary.

When I ordered new panels yesterday, I asked the HF sales rep if he knew of any manufacturing changes in the last four years that might improve Harbor Freight panel life. He said no.

I think it would cost them too much to add a UV coating to the panels, and their market is for folks who want a (very) low priced entry into greenhousing. To be honest I'd still buy one again, since it's still a great bargain for DIY types willing to modify the kit for strength (as shown in my blog in one of the previous posts.) But it's good to keep the panel drawbacks in mind, and don't wait until cold temperatures approach to check your roof! (Lesson learned...)
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