After a couple of weeks of inactivity, we began framing on Sunday. In fact, we did more than begin! My father-in-law has framing experience from building several houses, 1 wedding chapel and a number of other projects. He has been a huge help. In fact, he’s pretty much been doing the framing while I hand him the tools. 🙂 But I’m learning.
Even with several snags along the way, all of the walls were erected in a mere 5 hours. That included a couple of breaks to go and get supplies and to partake of refreshments and dinner.
The end rafters were also mounted. At the end of the day, I couldn’t help but bring out one of my new shelving units and sit a couple of plants on it in the greenhouse. I just wanted to get a feel for how much space the shelves would take up in the greenhouse. It’s very exciting.
I’m sure that the finishing touches will take a while, but I am very encouraged to see how quickly it has gone up so far. Soon we will be placing the door and adding the polycarbonate. Stay tuned!
In order to tie the masonry base of the greenhouse to the framing above, I had to affix anchor bolts to the cinder block structure. I used 10″ Simpson L-bolts and set them in concrete about every 3 feet along the top of the wall.
At the same time, I stuck a 24″ length of rebar in each of the concrete-filled holes, for better stability of the walls. After drilling precisely-placed holes in the base boards of the framing, we can now attach the walls to the cinder block and everything will be very solid.
I am using 1×6 decking boards to cap off the holes of the cinder block wall. These 1×6 boards will lay just beneath the regular 2×4 framing. Drilling the holes in the correct location was not an easy task, but the first board is now attached and the others should be a little easier.
As you can see, there is still plenty of room on the bolt to lay a single 2×4 lengthwise on top of the 1×6. Assuming I measured correctly when I set the bolts in concrete, the nut should be just at the top of bolt when the 2×4 is attached.
One of the requirements for us building a greenhouse on our back porch is that is must look nice from the outside as well as the inside. It can’t be some unsightly building with a garden of Eden inside. That’s why we plan to eventually cover over the cinder block with brick that matches our house. That’s also why we decided to stain all of our lumber before doing the framing.
Christie spent several hours over the weekend, staining our standard 2x4s and base boards, while I was finishing with the block laying. We chose a very red stain color, which matches the brick of our house very closely and contains all of the sealant stuff to help protect the wood for a long time. Hopefully we won’t have to re-stain the wood any more often than 8-10 years or so.
With the last block in place, we are ready to start the framing!
This weekend we got down to business on the greenhouse construction. I spent a couple of hours on Saturday gathering supplies. I made a trip to Lowe’s to get two truck fulls worth of lumber and cinder blocks. I honestly won’t need the lumber for a little while, but I wanted to make best use of the 10% coupon I had. I also purchased the mortar mix, rebar pins and anchor bolts that will be used in the construction of the walls.
The 60 cinder blocks were loaded into the truck with a forklift, but since I don’t have my own at home, they had to be unloaded by hand… That’s a lot of blocks.
On Sunday, we got to work. (Although Saturday wasn’t exactly sitting on our butts!) Christie and I carefully chalked the perimeter of the greenhouse. Then I laid the first bed of mortar and carefully placed the first block.
The first couple of blocks were frustrating and tedious. But a couple of blocks later and we were cruising. I had some help from Christie and her dad and we were able to complete much more than I had expected!
After we were finished laying block for the day, Christie meticulously cleaned the tools and the work area, making sure that all of the mortar lines looked clean and filled.
Recent growth in my plant collection has highlighted the inevitable – I’m going to need a greenhouse sometime in the future. And that future seems to be quickly approaching. For quite a while I have thought that a greenhouse might be possible sometime in the future, but we recently decided to go ahead and do it now.
Plants are almost literally growing out of our ears! We need someplace to put them. While my wife and I love our little house, it is lacking in the number of windows needed for happy houseplants. During the winter months, our house stays at 60F most of the day and we only turn it up to 62-63F when we are going to be at home for a while and get cold. The plants would prefer 80F and 80% humidity.
A greenhouse can provide that kind of growing environment on winter days, by simply taking advantage of the sun’s awesome power. I intend to take advantage. On winter nights, a heater is required.
In the next month, we’re going to build a small greenhouse on our back porch. The area we have to work with is about 8’x12′, so the inner dimensions will likely be about 7’x11′. This area is pretty heavily shaded during the growing season by our huge Sycamore tree. When Fall arrives and the temperatures drops, so do the leaves. At this critical time of the year my greenhouse will receive the most light.
One wall of the greenhouse will be shared with the exterior of our house. The roof of the greenhouse will adjoin our house roof.
I plan to lay 2-3 layers of cinder blocks and then build a simple wooden frame out of 2″x4″s on top of that. I have experience laying cinder block from house-building mission trips to Mexico. My father-in-law has built several houses and will be helping with the framing. The walls and ceiling will be covered with 8mm triple-wall polycarbonate sheets. Twin-walls are a little cheaper and more common, but the cost differential is quickly paid for with reduced heating costs and size of heater needed.
The polycarbonate sheets can be attached very easily by nailing/screwing them into the wood frame. Additionally, you have to seal all joints to avoid leaking the warm, humid air of the greenhouse.
To cover the screws or nails, you cover the polycarbonate joints with trim wood. I plan on cutting my trim pieces to fit and then staining and sealing my trim pieces before attaching them to the greenhouse.
I will buy a small space heater that will run in the greenhouse during the winter months over night. During the day, it should stay pretty warm, even when the temperatures outside are cold. I have used a calculator online to determine the BTU output my heater will need. Assuming the temperature falls to about 20 F outside and I want my greenhouse to stay at or above 60 F, I will need about 500 BTUs to heat the greenhouse.
I ran some rough numbers and have an estimated cost of the main materials. Those materials are the lumber, cinder blocks and polycarbonate sheets. They are the most costly and also the easiest to figure. For instance, I know almost exactly how many cinder blocks I’ll need, but have no idea how many nails.
My initial estimate doesn’t include all of the fasteners (nails, bolts, etc.), sealers, stain, or bags of mortar and cement. Other considerations are any extra tools for building (beyond what I already own), the exhaust fan, and a simple fluorescent light fixture. I plan to find some cheap shelves and build the remaining ones to fill the space inside.
All in all, I figure the total cost won’t be much more than 50% greater than my initial estimate for the base materials.
Room for improvement
Over the years the greenhouse will probably undergo a number of changes. I’ve already thought a couple of them through. We would like to add a room onto our house one day. At that time, we will be ordering bricks to match our house. I would like to have a professional mason cover over the cinder blocks with the matching red brick, so I will be leaving room on the back porch pad when I lay the cinder blocks.
Another upgrade I foresee is incorporating irrigation in some way. I’m not sure how I want to do this and I think I will probably have a better idea after the greenhouse is built. For now I’m going to just drag the hose in through the door or use a watering can. One potential watering system would simply be to collect rainwater runoff from the roof and route it into a container in the greenhouse. There are a couple of areas around the house that would benefit from gutters diverting heavy rains to other locations.
Other potential upgrades include improved circulation, ventilation or heating.