I have chosen a 5 12 pitch for my greenhouse but ceres greenhouse states even a 3 12 is fine if you have a front wall with windows.
Greenhouse roof pitch uk.
In the usa the range of standard pitches is anywhere between 4 12 and 9 12.
In areas with heavy snow at least 3 or 4 feet is good to have so that snow won t pile back up onto the greenhouse roof or obstruct any vents.
We recommend choosing a practical height usually a maximum of 9 11 for residential solar greenhouses and then using the adjusted rule of thumb to ensure that the glazing meets the minimum pitch for light transmission.
What the materials the roof is made of certainly counts.
Framing and glazing materials.
Obviously aluminum and glass or lexan would weigh less than wood and glass or lexan but if your issue is angle then you have to consider the weather.
A steep roof pitch also means that there will be more working height above the greenhouse staging.
In the write up it states the future greenhouse will have a simple shed style roof slanting to the south but with a much lower angle to allow for a knee wall which will push the ventilation wall further up.
In order to achieve this goal a glasshouse should be selected with a steep pitch of roof at least 25 degrees or greater from the horizontal.
In the uk the typical house has a pitch between 40 50 although 45 should be avoided.
The two most common framing materials are wood and metal.
Related to the roof slope is the freeboard the space between the lowest point of the roof and the ground.
12 foot rise for 12 foot run.
There is no standard universal roof pitch.
This reinforces the natural chimney effect of hot air rises.