The Right Sunroom Size for the Right Plan

[ebass]

  Ideally, I'd like it to be a room, 12x12 or 8x12.......something with enough room to sit in.

[Amanda_931]

Me too.

Some friends have two serious greenhouses.  The small one, where they start (thousands of) seeds, attached to the house.  It consists of a couple of potting benches, water faucet, places for the hanging baskets, lots of openable windows for the summer, a couple of barrels of some kind of (silicone?) fluid to hold more heat.  Translucent, double layer polycarbonate glazing.

And a blower to pipe warm air into the room in the house that is just north of the greenhouse, set to turn on at 80 degrees.  It does this with any encouragement at all on most winter days.

But I kind of doubt you'd want to use it as a sitting room.   For instance, that 80 degrees F when the blower kicks in, is really very hot when the rest of the house is in the upper 60's or low 70's.

The other one is freestanding and big--the one to open up and, shudder, start heating,  as the seedlings grow and get transplanted.

It may be what you--and I--really want is a conservatory.  Something to use as a room.  With glass to take out in the summer so it's a screen porch.  

[ebass]

 I've spent some time in the Middle East, in a desert area where the daytime temps can reach 130 deg. F...........so in my case, 80 deg. might be ok...........still, I like the idea of being able to open windows........and being able to pipe hot air from a sunroom/greenhouse is, no doubt helpful........

Your friends' small greenhouse sounds interesting........
A conservatory sounds like an interesting idea, too.......got any pictures or plans that you can post?

[Amanda_931]

The link will send you an ancient picture of Doug and Claudia's house.  That front is facing dead on south.  They say that they rarely have to add heat, and with a large awning/pergola, a small window air conditioner keeps it cool in summer.

There is so much thermal mass in this house, back side is mostly buried in the ground, that it's hard to say how much the greenhouse really adds to the equation--or how much  the fact that it is right in front of some more south-facing windows subtracts from the study and living room.

The room (study, beer-making, computer, drying clothes in the rain) directly behind the greenhouse is the one with the blower.  Although it's a small room and part of the living room is also in front of the greenhouse.

I house-sat for them once in the wintertime and the house was never unpleasantly cold, and there was always enough hot water for a bath, even if I didn't turn on the water heater.

By contrast  my travel trailer sitting in the frost pocket down by their big greenhouse went through propane like mad.  

Scroll down about 2/3, and there's a picture of the interior of the greenhouse.

http://www.countrysidemag.com/issues/2_1998.htm

I haven't found a nice on-line conservatory picture yet, though.

[Amanda_931]

I may be wrong about the definition of a conservatory.  Links I found seemed to indicate a translucent roof and if it was an English conservatory a gable roof with a decorative spine.

I was thinking of something more on the order of a room with walls at least half windows on three sides--plenty of light, but not necessarily overpowering in the summer.  more or less regular furniture.

[John Raabe]

The house I live in is the Solar Saltbox http://www.jshow.com/y2k/listings/55.html. It has a 14x26 unheated sunroom with five skylights and full south facing window wall. The sunroom is insulated both from the outside and the house. In winter the room acts as an unheated entry buffer and the sunroom has never reached freezing.

The window wall and skylights were built using these plans http://www.jshow.com/y2k/listings/35.html and insulated tempered glass panels from sliding glass doors. After 22 years the panels have recently been replaced due to leaking edge seals (fogging between the panels). About 20 years is the expected life of any insulated glass unit. I've also had to replace about 1/2 the insulated glass in the manufactured wood windows in other parts of the house. Bigger panels also seem to move and stress the seals more and therefore fail a little quicker.

There was one skylight that leaked, but only after the roof was redone. This was because the roofer didn't do the flashing properly. When I fixed that the skylights have been trouble free.

In my sunroom during the summer it never gets more than about 5º - 10º warmer than outside air (this without fan forced air flow). An all glass roof would be much more of a problem.

Starting in late February or early March the sunroom provides most of the house heating on sunny days. This will be true until about the end of October. Thus my heating season is about 6-8 weeks shorter because of the solar inputs from the sunroom.



PS - In the photo above (taken in 2002) two of the panels have lost their edge seals. Can you tell which ones? They were replaced that year and now the others look the same as those and will be done later this year.