I have a diy greenhouse built out of cinder block and glass panels & 2 x 4s built up against South Wall of house as 4th Wall of greenhouse. I need to rebuild hole new roof. My question is. What is best material to use? I want to put in a. Couple of vents. Measurements are 12 x 14. Any advice? Thanks

My first choice would be to use twin walled polycarbonate panels. Since your greenhouse has a wood frame, they would be easy to install. You can get them in 2 x 4 panels and put in your own vents. Twin walled polycarbonate would also help to diffuse the sunlight hitting your plants.

If you can't get them locally, Greenhouse Megastore has them starting at $16 a panel. They also sell the fasteners and sealing tape.

I need to replace all the roof 2 x 4s I used treated lumber last time but they still rotted. Could I use the metal 2 x 4s? Thanks

Yes. You will need glazing caps and bars. See the Recommended Accessories on this page: http://www.greenhousemegastore...

After several years my family redid the roof of my greenhouse. I kept having problems with the old roof which was made out of corrugated fiberglass panels. The high winds we get here kept tearing it off.
The new roof is made from wood osb sheets and 2 large sunroof pannels plus metal roof panels like they use on metal buildings. It is so much stronger then the old one. I was worried about the loss of light on top but the plants seem to be doing just fine. The whole south side is made from 4 sliding glass doors plus one on the west side plus a solid glass door.
I also got a new misting system set up and my plants are singing
Can you here them?

Agoo said: After several years my family redid the roof of my greenhouse. I kept having problems with the old roof which was made out of corrugated fiberglass panels. The high winds we get here kept tearing it off.
The new roof is made from wood osb sheets and 2 large sunroof pannels plus metal roof panels like they use on metal buildings. It is so much stronger then the old one. I was worried about the loss of light on top but the plants seem to be doing just fine. The whole south side is made from 4 sliding glass doors plus one on the west side plus a solid glass door.
I also got a new misting system set up and my plants are singing
Can you here them?

Your plants must love the makeover. I can hear them singing from here.