Last winter I found myself doing whatever it takes to sit in front
of a south-facing window, which is pretty difficult in my house. So I
decided it might be worthwhile to build a greenhouse. So I got a
building permit and today I started preparing the site. I cleared
away some plants and came up with a 17'x6' area along the south wall
of my house:
I painted very professional surveyor marks to know where to dig to
put the block foundation, like this:
I went to a building supply store and got some concrete block:
and some basement-style windows (for ventilation along the
bottom):
and a sliding glass door:
Pile of concrete:
Pile of glass:
Ground is broken:
First section of first course of block:
Another site view:
Mount dirt:
First section up to three courses:
Extended a little bit:
All the way around, at least two courses deep:
On the 5th day, Greg rested.
Everything is up to three courses:
And this small section is its completed height:
I obtained:
(1x) 2"x8"x16' treated
(1x) 2"x8"x8' treated
(2x) 2"x4"x8' treated
(20x) 2"x4"x8' regular pine
Using this pickup:
An aside about lumber yards. For most things, I've been assuming that Lowes (big box store at edge of town) is cheaper than Bender Lumber (ye olde locally owned neighborhood lumber yard). I mean, Lowes is like the Walmart of lumber stores, if it's not cheaper then what really can it offer? Variety? A convenient location by the freeway?
But I go to Bender anyways because it's really close to my house. Anyways, today I actually looked at the receipts, and Bender is on average about 5% cheaper than Lowes for lumber! And Bender had every bit of Lumber I needed, even the 16' piece!
Sweet!
And I finished laying the rest of the block, with gaps for the windows
and sliding door, and one window placed (for example):
Today I finished off the last of the masonry work I think. I installed
the low ventilation windows:
I took some time off for interacting with the county building department. It turns out for detached structures of fewer than 120 square feet, I don't even need a building permit! Anyways, then it was way too hot out for building. It's been cool for a couple weeks now so I've been doing some work.
I have installed "sill plates" on most of the blockwork:
Those plates are
treated wood that is anchored to the masonry, and then all of the
framing just sits on top of that so it is protected from any
condensation at the top of the masonry or whatever.
I also started some of the framing, now that I have all of the
wood:
In the front are my two sections of window wall, for the south wall
(they are sitting on top of eachother, but will be beside eachother to
cover the full 16 feet). Behind that is a stack of 2x6s for roof
rafters. Behind that is T-111 plywood siding and chipboard roofing.
I went to "Re-Store", a Habitat for Humanity used building supplies
warehouse, to get some windows for the west wall. I found a couple that
fit my needs:
You know, your basic double pane crank-style windows.
So I found a humanitarian there and commenced haggling:
greg. Well, I have up to $100 budgeted for the pair
humanitarian. These look like $35 windows, how does that sound?
greg. Sure (starts counting twenties)
humanitarian. Look how dirty they are... $25?
greg. Ok...I think I can clean them
humanitarian. And look at this rotted wood on the sill!
greg. I was just going to rip off the sills anyways
humanitarian. Okay, how about $15?
At that point, I feel like I should have said:
greg. But look at this screen, it fits securely and it looks good as new, how about $20?
But their anticapitalist tact threw me off so I wasn't really on top of my game and accepted the windows for the price they suggested.
...
I dug a hole, about 3 feet deep by about 9 inches diameter:
And this is the post that goes in that hole:
It will be the center back support for the roof. It is about 3 feet
longer than it needs to be (the roof will be just higher than the windows).
I put up some wall:
The east wall (far) is a big opening for a sliding glass door, and the first segment of the south wall (windows) is up too. The second segment is in position and ready to go up when the west wall is completed for it to lean on.
I put up the rest of the wall:
The west wall (near) has openings for two windows at the top, and the south wall is all the way up. Now to finish the main roof supports..
I put up the center post today:
I sunk it into concrete:
I put up the main back roof support beam:
I got Wes over to help carry the sliding glass door into position:
And I installed the rafters:
Getting the chipboard up to the roof was fun but is now done:
The tarpaper was no big deal, but that stuff is *hot* in the sun:
And I managed to install most of the shingles before it got dark:
I left the top row incomplete so I could get some flashing to make it go right up to the house.
I finished the roof:
I added some plastic (moisture barrier) around the walls where siding
will go:
And I installed siding on the west wall:
But I ran out of siding, so I will do the east wall later:
I finally finished off the rest of the siding:
I've been priming:
And I installed one window pane to make sure I had the idea down, and I think I do:
I've been doing windows all last week, finally finishing the outer panes (of two-pane windows) for the complete south wall:
Close-up:
Painting is the only outside task left that has to be completed before it gets cold (paint likes warm days without rain).
Since it is going to be cold and rainy forever and "great stuff" foam in a spray can doesn't list a minimum operating temperature, I decided it was time to make the structure mostly airtight. So I foamed above the windows:
,
along the gap between the greenhouse and the wall of my house:
,
and around the refurb windows:
I tricked Katrina into painting by letting her pick the colors (Amazon Moss, Dark Royal Blue from Benjamin Moore):
And I've been doing the inside windows (about 2/3rds done):
And now the painting is complete:
It is time to move mount dirt:
So I cleaned the greenhouse for the first time:
And used mount dirt to fill in the gap between the block wall and the dirt floor (because the ditch I dug is slightly wider than a block):
And today I mostly finished dissipating mount dirt to the four corners of the yard (well, mostly I used it to make the grade slope away from the greenhouse for drainage):
I hung the fiberglass insulation (nasty stuff!):
While standing on this low-cost scaffolding:
Finito! Well, sort of. I finished all of the construction tasks, now it's all about the mechanical (such as temperature and humidity monitoring/control).
Many weeks ago I put plastic over the insulation:
Then over the last couple weeks I've been putting up my low-cost interior wall paneling of choice: luan 1/4" plywood underlayment (for putting under carpets). I'm used to drywall, so 1/4" plywood was a treat. It is so light I was able to install the ceiling panels unassisted:
Today I hung the last of the panels and did some other final touches, and cleaned out all of the construction debris and tools and so on. Then I put together a quick-and-dirty bench for plants to sit on:
I have been building a thermal monitoring system for my whole house so that I can run fans and so on to control the temperature in the greenhouse, and also so I can replace my aging analog thermostat (my computer will control the house's furnace). It is probably a bad idea because a computer has a lot more potential points of failure than a dedicated thermostat, but I will leave both hooked up so you can flip a switch and switch back to the old thermostat in case of failure..
So my design is to have a bunch of temperature sensors scattered throughout my environment, using I2C to talk to an I2C hub attached to my PC's parallel port. So I built a prototype I2C hub and prototype temperature sensor in my workshop:
Then I built a bunch of little temperature sensor modules which look like this:
That is a regular el cheapo phone jack that you have probably seen before (it is a convenient case). 0x69 is its I2C address (each sensor has a unique address). The two probes coming out the top have temperature sensors (LM35s) at the tip, and are approximately water resistant (this one is covered in electrical tape...the later ones used epoxy). So one temperature sensor measures ambient "dry bulb" temperature, and the other will be stuck in wet gauze to measure "wet bulb" temperature so that relative humidity can be computed from the difference.
Here is the little board I put inside of them, with a PIC12F675 (tiny 8-bit 4MHz processor with 4-channel analog digital conversion):
Here is the I2C hub I built. It is just a 74HC574 8-bit CMOS latch which I use because I can't stand the unreliable TTL signaling levels on PC parallel ports:
Here are four completed sensor modules:
Here is the one in my basement, fully configured with wet gauze and reservoir:
