Pitch slope the pitch or slope is the incline of the roof expressed as a fraction describing the rise over the run.
Porch roof truss spacing.
A house attached patio roof takes advantage of the house s structure by supporting one end of the roof on a ledger mounted horizontally to the house.
The spacing between rafters in a given building is part of the engineering calculations that determine the required structure of the roof.
Locating and mounting the ledger is normally a fairly easy process.
This sizing guide for roof rafters will help determine what you need for your small project.
The rise will be the elevation change over the 12 inches.
The roof truss spacing standard is important because eighty percent of new homes are built with standard pre fabricated trusses.
However if the spacing is too wide the patio cover s beams will bow under the weight of the joists and roof covering materials.
Other relevant factors include the type of wood being used for the rafters the size of the rafters and the load that the rafters need to support.
This means that if you re in charge of repairing or installing roofing trusses you ll be expected to hold to these standards.
We show you the steps involved and calculations required for buildng a roof for your porch or constructing one over your deck or patio.
These standards are as follows.
To determine how many trusses to create you will first need to measure both the width and the length of the structure you are building.
The ledger should be attached.
The same thing is true for the bridge of the truss.
We show you how both a typical rafter style porch and truss roof area constructed.
Maximum rafter spans for a patio roof.
Weather you re building a shed roof or adding a dormer to your second story it is important to choose the proper size rafter.
In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
An essential part of planning a patio roof or gazebo project is determining the number size and spacing of rafters beams and posts according to the loads they will carry.
For heavy roofs or in.
The trusses should be a little longer than the exact width to allow for overhang and you will need sufficient trusses to mount across the length.
Follow this guide to ensure the spacing and stability of your diy roof trusses.
The determining factor of post spacing is the allowable span of your beams.
Typical roof truss.
Standard roof truss spacing.
Finally the truss calculator will compute the best dimensional method to connect the pieces of the truss with steel joints and a bridge.
For example a slope of 6 12 means for every 12 inches of horizontal distance the slope of the roof will rise 6 inches vertically.
The more complex the truss framework is the greater quantity of these joints will be required.
Building a porch roof requires basic carpentry and porch roof framing knowledge.
In other words the maximum distance it can cover without support from posts.
The run or the base number is 12 inches.
