Barn Greenhouse

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Barn Greenhouse

Free step by step plans to build a barn style greenhouse!

HANDMADE FROM THIS PLAN >>

Projects built from this plan. Thank you for submitting brag posts, it's appreciated by all!

Author Notes: 

I have been dying to show you my Mother's Day present.

For years and years and years, I've been wanting a greenhouse. Up here in Alaska, the only way you are going to eat cucumbers or tomatoes off the vine is to grow a greenhouse. Or steal from your Mom's greenhouse.

But every year, every spring, we just have so much going on, the greenhouse never happens.

Next year, we say.

I thought next year would never come.

We were already saying next year this year.

So I tried something different

I said, what about tonight?

We started cutting boards at 4PM that night.

By that evening we had completed all of the wall framing.

I was so excited couldn't stop myself from sharing a pic via instagram and twitter!  Jaime from That's My Letter also sent me a work apron that is just so beautiful I was afraid to use it!

That first night, we actually called it an early night!

The next morning, we got up and assembled the panels in the driveway.

We used roofing tin for the side panels.  It's relatively inexpensive and easy to install and will last much longer than plywood.  And I just liked the look of it too.  I designed the plan so each side uses uncut 12 foot long panels to save time and minimize scrap waste.  

The corners are trimmed in simple metal flashing.

For the greenhouse panels, we used the ribbing strips, but they aren't entirely necessary.  We started the ribbing strips so that the corrugated panels would come up just perfect to ..... 

Wrap the top rib of the corrugated roofing!  It was a happy accident for us, but I hope if you build you will consider wrapping the corrugated plastic over the roofing - makes for a good seal!

All of the panels are predrilled

To prevent screws from splitting the plastic panels and wood.

We were surprised at how many screws we ended up using!!!  We used metal roofing screws.

Up to this point, we have not had to cut any panels!  The sides of this greenhouse plan are made a perfect 12 feet long so you can just buy 12 feet long panels and slap them up!

Of course, the greenhouse is also designed to use the widths of the panels, so no ripping panels down.  

But on the gambrel ends, we will need to cut the panels to match the roof line.  We simply held the panels up in place and marked the cuts with a pen.  Then we used a chalkline to make perfect straight lines across ribs and cut with a circular saw as directed by the manufacturer.

Grandpa Tim helped us out with this project.  We are very grateful for all his help and expertise.  

The ends panels are screwed up without the ribbing strips.  

We'll be adding the flashing up to the outside corners as well.

And after years and years of waiting, within a matter of a few days, working on the greenhouse here and there, we had this!!!!

We choose the gambrel or barn style roof design because you can get more headroom inside while still having lots of room up top for greenhouse panels.

  We love it.

And I wanted to get the plans out to you as soon as possible so you can also build it!  Enjoy the plans!

Shopping List: 

Materials for 32" stud walls -

3 - 2x4 @ 10 feet long - use on back wall
5 - 2x4 @ 12 feet long - use on sides/ridgepole DO NOT CUT)
32 - 2x4 @ 8 feet long
11 - 12 foot long x 26" wide standard corrugated plastic greenhouse panels
1 - 8 foot long x 26" wide standard corrugated plastic greenhouse panel (use on door side)
3 - 12 foot long tin panels (use on sides and back)
1 - 8 foot long tin panel (use on front)
Tin screws
28 - 4' long ribbing strips
L flashing (optional for the corners)
You'll need either metal gussets for the trusses or to cut plywood ones from 1/2" plywood. We used scrap plywood from the Momplex need about 1/2 a sheet.

- Will make door in later plan

3 inch screws
wood glue
Tools: 
measuring tape
square
pencil
hammer
safety glasses
hearing protection
drill
circular saw
compound miter saw
level
countersink drill bit
General Instructions: 

Please read through the entire plan and all comments before beginning this project. It is also advisable to review the Getting Started Section. Take all necessary precautions to build safely and smartly. Work on a clean level surface, free of imperfections or debris. Always use straight boards. Check for square after each step. Always predrill holes before attaching with screws. Use glue with finish nails for a stronger hold. Wipe excess glue off bare wood for stained projects, as dried glue will not take stain. Be safe, have fun, and ask for help if you need it. Good luck!

Dimensions: 
Dimensions are shown above.
Cut List: 

Cut list is in plan at each step

Step 1: 

2 – 2x4 @ 118 3/8”
6 – 2X4 @ 32”

NOTE: I made the studs 32" long to conserve 2x4 boards. But this meant we had to rip our tin sheets down about 3" because our overall side wall height ended up being 35" and the tin was 38" wide. You can alter the studs to avoid this problem or even make the studs 45" tall if you choose to use 1/2 sheets of exterior plywood creating 48" tall walls for a taller greenhouse.

We framed everything up with nails and a nail gun and glue. You can also use 3" exterior screws.

Step 2 Instructions: 

4 – 2X4 @ 144”
14 – 2X4 @ 32”

Same is true again of the stud lengths.

Step 3 Instructions: 

4 – 2X4 @ 32”
4 – 2X4 @ 42 ½”
2 – 2X4 @ 81 ½”
1 – 2X4 @ 33 3/8”

Note: If you later the stud length, you will need to then alter the door framing studs to the exact difference.

Step 4 Instructions: 

We actually put the tin on the side panels first to save some time and work. The panels are just screwed together as shown here.

Step 5 Instructions: 

4 – 2X4 @ 48” (BOTH ENDS CUT AT 22 ½ DEGREES, ENDS NOT PARALLEL)
2 – 2X4 @ 39 5/8” (LONGEST POINT MEASUREMENT, ONE END CUT AT 22 ½ DEGREES OFF SQUARE)
2 – 2X4 @ 48 1/2” (LONGEST POINT MEASUREMENT, ONE END CUT AT 22 ½ DEGREES OFF SQUARE)
2 – 2X4 @ 42 1/4” (LONGEST POINT MEASUREMENT, ONE END CUT AT 22 ½ DEGREES OFF SQUARE)
2 – 2X4 @ 7 3/8” (TOP CUT TO DOGEARED POINT MEASUREMENT, TOP END CUT AT 22 ½ DEGREES OFF SQUARE)

We layed the truss out on the garage floor and everything worked out perfectly. We used scrap 1/2" plywood to create gussets but you can also buy metal gussets for the joints. Gussets are simply plywood pieces cut to cover joints and then screwed on with glue. We use 3-4 screws per board covered by the gusset per gusset, with normally gussets on each side of the joint.

Since we knew the end trusses would get the panels applied, we opted to only put gussets on the insides.

We attached the front truss to front wall with screws through undersides.

Step 6 Instructions: 

4 – 2X4 @ 48” (BOTH ENDS CUT AT 22 ½ DEGREES, ENDS NOT PARALLEL)
1 – 2X4 @ 117 7/8” (BOTH ENDS CUT AT 22 1/2" DEGREES, ENDS NOT PARALLEL)
1 – 2X4 @ 55 3/8 (TOP CUT TO DOGEARED POINT, 22 ½ DEGREES)
2 – 2X4 @ 55 ¼” (TOP CUT TO DOGREARED POINT, BOTTOM CUT 45 DEGREES OFF SQUARE, END CLIPPED)

The back truss is built same as front. See next step for close up of the center cuts ...

Step 7 Instructions: 

This board was a little tricky to cut - practice first!

Step 8 Instructions: 

1 – 2X4 @ 141”

NOTE: If you use gussets - we used 1/2" plywood - this will affect your ridgepole length.

TIP: I learned this from the Ram. Take your ridgepole BEFORE attaching to trusses and set it on the side wall. Then just mark all of the side wall stud locations on the ridgepole. Do this on both sides of the ridgepole. Then screw the ridgepole up in place. It will be marked now for the common rafters!

The ridgepole actually sits down from the end truss peak about 1/4". This is shown in the diagram as well.

Step 9 Instructions: 

10 2X4 @ 48” (BOTH ENDS CUT AT 22 ½ DEGREES ENDS NOT
PARALLEL)

10 2X4 @ 47 1/4” (BOTH ENDS CUT AT 22 ½ DEGREES ENDS NOT
PARALLEL) - shorter rafters go up to meet the ridgepole.  I marked all shorter rafters to avoid confusion.

For the common rafters of this barn style greenhouse, we ended up using plywood gussets to save money. After cutting quite a few, I figured out how to cut gussets the super quick and easy way - got gusset cutting down to less than a minute each.

Going to apologize for the poor video - just wanted to show you quickly how to save some time and didn't have time to call hair and makeup :)  had a greenhouse to build!

We put gussets on both sides of each rafter joint with glue and screws. We made all of the small trusses first on the ground, then it was just a matter of stacking them on the ridgepole and attaching to the studs. We used 8 screws per gusset.

Common rafters are installed flush to top of ridgepole and flush to outside of side walls. We had to "toenail" the screws in - meaning they are screwed in at an angle. We used glue and 3" screws from both sides.

Step 10 Instructions: 

The plan will get you through the framing. At this point, you could use plastic paper, lexan glass panels, you name it to seal the frame in. We used the corrugated plastic panels detailed earlier for installation.

IMPORTANT: If you do not use panels you will need some sort of lateral support to keep the greenhouse from swaying side to side. Try 12 foot long 2x4s.

Good luck! We'll be building the door in the next few days and adding plans as well.

Preparation Instructions: 
Fill all holes with wood filler and let dry. Apply additional coats of wood filler as needed. When wood filler is completely dry, sand the project in the direction of the wood grain with 120 grit sandpaper. Vacuum sanded project to remove sanding residue. Remove all sanding residue on work surfaces as well. Wipe project clean with damp cloth. It is always recommended to apply a test coat on a hidden area or scrap piece to ensure color evenness and adhesion. Use primer or wood conditioner as needed.
Project Type: 
Room: 
Skill Level: 
Style: 

Comments

I am SO glad to see this project! I have also wanted one for several years now. could you tell me approx what this cost for materials?
The DIY channel really should hear about you!

Ana -
Even in Alaska you will need vents to keep from cooking your plants.

Love this! Just wondering about what it costs to build? Couldn't find it in the description.

This project is awesome! I've been planning out how to arrange our yard - this is going to have to go into the plan. Love it!

Ana I am so glad to see the greenhouse finished. What a wonderful Mother's Day gift that was. Thank you for sharing the plans with us. Wishing you and your family lots of joy in your gardening adventures...Vi

Very nice job on this. Will be looking at this as a possible basis for the one we need to build, though it will have to wait til next year (this year I'm more concerned about the master suite renovations we're in the middle of.. the old man who built our house ages ago didn't understand the difference between dry wall and and the waterproof greenboard.. so we've had to gut and redo all the bathrooms one at a time. we decided to take the necessity and turn it into an excuse to redo the master suite the way we want, but doing it ourselves, on the weeks hubby's home from the slope, seems to be taking forever.. and there was a lot i can't/couldn't help with for health reasons.. but it's getting there..)
Meanwhile, I have 2 lovely bay windows that I use as an indoor mini-greenhouse.. keep my tomatoes and peppers in those and they do wonderful.. I'm in Palmer, AK and I have to literally kill them off or they would keep producing all winter. had one that got left in the bedroom all winter and ignored.. it has come back and is covered in new bell peppers. it's crazy :)

I of course would have no idea of how to do this on my own. Yet another reason you are loved by us all. I will totally be building one of these instead of buying when I get my spot of land!

Isnt it really nice to get what you want for mothers day. Ana I am so glad you finally got your greenhouse. I got a stanless steel laser miter saw. Now I can build almost anything, got my Kreg Jig for Valentines. Cant wait for my birthday next month. I am thinking air compressor. Keep bringing these wonder projects. I talk you up to everyone I know. Send them to you sight. Thanks for being an inspiration to all the women that think the could not come out of their comfort zone and create.

Thanks,

Emily

Thank you everyone for your wonderful comments! This was actually a very easy project! We ourselves couldn't believe how fast it came together.

We asked locally what people do for venting and most people said on a small greenhouse, having the door open provides enough ventilation. But if we find we need more, we can always add vents.

At this point, we are just looking for a greenhouse to grow tomatoes and cucumbers and herbs and peppers - just extending our growing season a little on each side. But we would at some point like to consider a true arctic greenhouse and I love the suggestions of creating thermal mass. Really got me thinking! Thanks for the input, we really appreciate it!

We designed this plan so it's exactly 48" on the sides. Anyone like to see this as a shed too???? I'd love to modify the plans!

Thanks again for reading and commenting!

I was just thinking how great this would be as a shed. I would love to build a space where I can store my tools and "play" with them too. Thanks Ana!

Ana,
You are, as always, impressive! I would LOVE to see this as a shed! We really need one and my husband loves this design.

Thank you!
Bryanna

I'm searching your newly found site now (found by googling loft bed) for a shed, and saw this.

I am curious how the clear corrugated siding is holding up (did you only build this in May 2012?).

I would really like to have this plan "converted" to a shed. Maybe with double doors (50+ inches on the opening) so I can drive the mower (48" cutting width) with ease.

Thank you for all the plans and ideas that you and your family are sharing with us all.

Hi Ana,

I'd like to see this greenhouse with a smaller footprint . Any outbuilding over 100 sq. ft. would require a permit in my city.

Thanks for the plans! This the the perfect fall work party project!

Hi! The easiest way to do a smaller footprint is to just make it 8 feet long instead of 12! Then you just buy 8 foot sheets of tin and greenhouse plastic, make the side walls 8 feet long instead of 12, and drop 2 sets of common rafters. Super easy mod and would get you just under 100 square feet :)

This looks about just the right size for my greenhouse!

I'll be curious to see what you do for winterizing it. Maybe use bubble wrap in "ceiling?"

Looks like it would support the snow load and I am thinking about heating with a fish tank -- about 500 gallons of warm water should be able to keep the veggies growing... and allow me to harvest fish too!

Thanks Ana!!!

Hi! The greenhouse isn't that heavy - we moved it by putting it on a trailer and then taking it off with just my husband and father-in-law. The best option is to build your trusses and walls on a flat level surface, and then assemble and add the tin and greenhouse panels in place.

I love this idea! And the step by step plans are wonderful! Can you give me a guesstimate of the cost to build this they way you built it?

This looks easy to build, we like the basic structure, but may use corrigated plastic panels on the sides as we live in a cold area of vermont.
Thanks

Hi Ana: I too would love to see this plan as a shed but a bit smaller.

I also wondered about the venting. I don't think that it could be used during the hot summer months around my parts. Then again there is such a product as shade cloth.

I'm in Alaska too and I was wondering what it cost to build this. I also want to be able to grow stuff like tomatoes, peppers and herbs. We have done cold frames made out of pallets but I would like to build a greenhouse.

As I was reading the plans I was trying to figure out how to make it a shed. I would love to see the plans.
Thanks Ana for all you do. I started building a few weeks ago and dont want to stop.

Love this , just emailed it to my hubby in hopes that he gets inspired to build this for me as i love to garden and this is perfect ... thanks for sharing .

I noticed that you placed the clear roofing side ways on the greenhouse instead of placing it vertical so that the rain and snow would run off faster. Did you have any problems during this last winter in Alaska with the snow load? I built a similar shed last year and the roof was strong enough for all the snow this year. Here are the plans, http://www.mybackyardplans.com/gambrelstorageshed.php

Thanks
Darlene

I agree with Darlene. The ribbed panels need to be vertical to shed water. With your horizontal panels the water will run to the ends and then soak into the wood framing. I would expect the wood at the front and back of your greenhouse will begin to rot sooner rather than later.

I am new (just today) and have seen some of your plans. I am awed!!! But when I saw this... OMG... I was in love. I have been wanting a greenhouse for quite a while now and this is actually something attainable for me. Thank you so much for all your sharing and keep up your wonderful work.

I would LOVE to see this as a shed. How hard would it be to make it two doors wide and a bit longer? This looks like just the shed we need for all our gear for our trips :) always an Ana Fan!!!!!

<>< Tamara :0)
Philippians 4:6

Ana

Where did you get the ribbing strips for the corrugated? I would like to build your shed / greenhouse and send you pics! I already have the space and we are leveling now!

Well now, that's about the cutest lil greenhouse I ever did see! My husband and I were inpsired. We bought the materials and we'll be constructing the "lil cutie" next week. I read the post about the horizontal placement of sheeting along with the one on venting. Snow is not an issue in our part of Texas but we do have lots of rain. We are using environmentally recommended treated lumber for the entire project. I will take notice and comment how it holds up over time. (I do not think it'll be a problem) We will, however, need some sort of venting for mid summer as it's disgustingly hot down here. However, we thought the plan was laid out perfectly fine for our needs. We will figure out the venting problem next summer. I'll let you know how it works for our weather and I'll post a link to your site onto our site along with pics after it all said and done. Thanks again!! The Reshards

Seriously...the Gambrel framing is great however Ana got it all wrong with the corrugated polycarbonate (not corrugated glass as she stated). Rain or snow it will rot the wood eventually because water will leak in. Also she should have used foam gaskets/inserts instead of wood. Wood will rot.
Here's a link for Lexan Corrugated Polycarbonate panel installation

http://www.hobby-greenhouse.com/lexan.htm

Actually the metal side walls should be vertical as well.

Ana,

Can't thank you enough for the plans, we've been looking for some plans for a long time now.
However I will build the greenhouse double length, I need a larger greenhouse and will make the pitch on the roof steeper.

A vent is a must and if I need heat then I will build one of this solar panel: http://blog.hemmings.com/index.php/2007/04/26/almost-free-garage-heat-ju...

Good luck planting your dream garden.

This is amazing! Thank you so much for sharing the plans and sharing the knowledge to the community out here! We appreciate it. I know what you mean about putting things off until you decide "why not RIGHT NOW?" That's how I've finally started getting things done!

I miss Alaska like crazy; I love living vicariously through other people's blogs!


Liv

Hubby and I want to have a green house really bad and this just might fit the bill.
Wondering if you secured it to the ground? We get wind storms and I know that it blew away one of those metal kit garden sheds you can buy.

I really like the looks of this greenhouse. It also looks easy to build. What I have a question about is, shouldn't the plastic greenhouse panels be turned the other way for people who live in the Northern climates where there is sometimes 1-3 ft. of snow? Othen that I really love this idea.

Nice page however it's unfortunate you attached the corrugated polycarbonate horizontally which is not recommended by Sabic, Sun Tuff etc. The panel should be
installed with the hills and valleys aligned vertically. This allows snow ( I would imagine in Alaska you get plenty of snow) to slide off the roof and looks a lot better. See greenhouses at hobby-greenhouse.com to see what I mean they use Lexan Corrugated I purchased on a few years back.

We need to save our environment so that our future generation can have a secure shelter. The more we resort to nature and its elements the better for us. Medicines that are made with herbal essence are way better for you. For instance, Kratom has healing properties, so look for natural solutions for you, this is the best way to save our dear old planet.

Hi there, I am semi retired and my wife and I are looking to open a small Business on our 30 acres. We both love gardening and making candles, birdhouses and such. I am curious about the greenhouse plans I found of yours while searching. I see people asking about a smaller version but what if I make it say, 20 ft long? Just adjust the measurements as I would with the shorter version I would think. I would like to attach a shed, store to it and it looks like if I build the trusses closer together it would take the winter snow. I may just make the outside walls higher for the head room and butt the greenhouse to it. Any thoughts? Am I on the right track with it? Thanks in advance, Jack and Pam

hey ana the green house looks great i just have a few questions 1. Im relatively new at this and my husband and sons and ok me we built this beautiful green house frame out of angle iron and outside out of plexiglass we snagged a deal at the local restore from habitat for humanity but the plexiglass is not durable on the outside so we r going to have to replace it with that corrugated stuff you have on yours,Im curious if it islong lasting in the conditions up there in alaska and we were thinking of angling it the other way so as to allow the snow here in utah to fall off the roof but still not sure give me your best synopsis please. 2. also the heating and cooling we only need it for maybe a 6-8 weeks prior to planting so the best possible economical outcome that you have found woud be most helpful. excited spring planter Teresa!

When you want to get a project done you should start as soon as you can or else you have to keep postponing it every time. But before you start you should do a little research on the project, you have to be sure of the materials that you need and their quantity. When it comes to paint colors you learn about the The Hottest Paint Colors and pick the one you like best.

What a wonderful project. Where I live -- I rent -- there was a greenhouse, once upon a time, but it collapse as nobody took care of it. Sad! But, the huge ciment pad with drainage and else is still there as wel as the anchors all around. it would be a great idea to do something with this. Electricity, water is still there and working.

Hope you will post some photos of the wonder in full production! Will you? As for the inside, will you put just tables all around or make raised beds?

Other question... I see you put a metallic frming all around. Did you put some insulation also to go further in time in your production?

Looking forward to read about the evolution of your project

Ana,

I just discovered this plan. Yes, yes, please, oh, please on the shed plans. We really need a shed now that my newly found love of building has taken over the garage. I would really like to build a shed and I love this design, maybe with a few of the clear panels for skylights?

Thank you for everything you do and for inspiring me to learn the best hobby ever!

The Lexan / SunTuff Corrugated Panels need to be installed horizontally and foam gaskets / inserts used instead of wood. They are called the Greco Profile.
Rain or snow water and moisture eventually rot the wood because water will leak in. Also snow will pile up causing stress on the rafters, rain will not run off and will leak into the gable ends.
Here's a link for Lexan Corrugated Polycarbonate panel installation.

http://www.hobby-greenhouse.com/lexan.htm

Here's a video to help you:

http://youtu.be/DysihGdfmaM

Actually the metal side walls should be vertical as well but that is not as critical as the corrugated panels being propely installed.
The Gambrel frame is okay but I don't understand why they didn't use a waterproofing stain even on the interior,
It seems you get a lot of visitors so you need to tell them to do it correctly or your followers will be sorry they used your plans. I'm not trying to be a boor just trying to help. I build cedar greenhouses covered with Lexan Corrugated. Anna if you need advice or assistance you can email me sales@hobby-greenhouse.com

I found this greenhouse last year when I was searching for plans. I added it to my list. Well, a year has come and gone, and I am going to build it this summer. I read the comments about the way you ran the Lexan, and I am just wondering...how has your greenhouse held up? I was going to follow your plans exactly, but if you have had any problems with it, I'll apply the Lexan vertically. It just looks easier to do it the way you have it in the plans. And, if it is doing well, why should I fix something that isn't broken. LOL

I know it was talked about at the beginning of this post regarding converting the plans for a shed. I know you've been busy creating life by way of baby and television show. Just wondering if this was something that was still in the works. If not I will fly by the seat of my pants since I've had a few builds and feel like I could. Thank you in advance.

Absolutely LOVE the greenhouse, thanks for offering the plans! I've wanted one for a long time. Oh, the apron is adorable and looks great on you!