Replies

1. GBA Editor
   Martin Holladay|May 02, 2017 12:13pm|#1

   Kurt,
   The easiest question to answer is the last one:
   Q. "Will south facing single pane glass loose heat on cloudy days?"

   A. Yes, unless you limit your definition of "days" to mean "the part of the day between 10:00 am and 2:00 pm" and unless you limit your definition of "cloudy" to mean "with only a very thin layer of translucent clouds."

   Q. "What is the best glazing option for balance of heat gain/loss on cloudy days?"

   A. There is no easy answer to your question. You will need to compromise. Glass with a low U-factor (for example, triple glazing with two low-e coatings and argon gas fill) will have less heat loss on cloudy days, but most types of low-U-factor glass also have a lower SHGC. High-SHGC glass (a single layer of low-iron glass) has a high U-factor. There is no magic glass with a very high SHGC and a very low U-factor.

   For more information on this issue, see关于玻璃的所有选择.

2. 
   kaf2303|May 02, 2017 04:05pm|#2

   Thanks for the quick reply Martin,
   Since It will need light for the plants and heat for the fish I'm probably better off with 2 or 3 layers.
   Any suggestions for sourcing glass units in the 6'to 6-6 tall range?
   再次感谢，库尔特

3. GBA Editor
   Martin Holladay|May 02, 2017 04:12pm|#3

   Kurt,
   Back in the 1970s, we were all using IGUs sold as "patio door replacement glass" -- the size was standardized and the price was cheap -- to build passive solar homes and greenhouses. You could ask local glass suppliers if they have any low-cost units.

4. GBA Editor
   Martin Holladay|May 02, 2017 04:16pm|#4

   Kurt,
   I used to buy these IGUs in boxes of 10 -- they came in a wooden crate. I still have a few in my basement -- just went down to measure them. They are 34"x76".

   我会说“让我要约”，但我真的不认为你想要它们。

5. 
   Stephen Sheehy|May 02, 2017 04:20pm|#5

   Kurt: If you plan on building a greenhouse from scratch, I'd look into polycarbonate panels.

6. 
   kaf2303|May 02, 2017 05:46pm|#6

   Thanks guys,
   I will look into those options .
   Martin how many do you have? Are they 70s vintage?location? I'm near Burlington,VT.
   Stephen what is the life cycle of the pc. Insulated panels
   Kurt

7. GBA Editor
   Martin Holladay|2017年5月3日04:42 AM|#7

   Kurt,
   我的igus不出售。他们已经存储了40年，您不想要它们。最近制作产品 - 理想情况下，一些具有低涂层和氩气填充物的Igus。

8. 
   Stephen Sheehy|May 03, 2017 06:51am|#8

   库尔特：我不知道聚碳酸酯面板持续了多长时间，但是它们比绝缘玻璃便宜得多。由于它们也更轻，因此建造温室应该更容易。我会去当地的商业温室，看看专业人士对聚碳酸酯的看法。面板有各种尺寸和厚度。

9. 
   kaf2303|May 03, 2017 07:07am|#9

   非常感谢Martin＆Stephen的建议。
   Best, Kurt