Builders aren t bound by standard rafter spacing measurements.
Pergola roof rafter spacing.
Maximum rafter spans for a patio roof 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.
To calculate your rafter length for a freestanding pergola it is measurement a 3.
10 1 6 1 6 13 rafter length of 13 feet.
Posts will be 6 x6 and will be notched to accept a sandwich beam of two 2 x s.
The key thing to remember when it comes to determining pergola rafter spacing is that you cannot go more than 16 inches from center to center between rafters.
Patio roof maximum beam rafter spans what is max distance between posts pergola main beams span building span tables for 8 x12 x24 western red pergola beam span calculator.
Install the front and rear rafters first fastening them to the face of the support posts above the girder.
But they do tend to space rafters in one of several industry standard increments typically either 12 16 or 24 inches apart.
When pergola rafters are on 2 foot centers 16 inch purlin spacing looks good.
The average pergola structure is usually between four and eight feet tall and eight feet and taller.
The most important rule in spacing is to keep the distance consistent between all the rafters.
Spacing of the rafters will vary according to your visual preference and the size of the pergola.
Across the beams the rafters will be 2 x6 s on 8 centers which should be sufficient given their 4 6 spans.
When rafters are on 3 foot centers i typically space the purlins 19 inches.
Since the cedar stock i use is cut green and contains a lot of moisture i usually allow it to air dry for a couple of months before i apply a finish.
The only hard and fast rule of rafter spacing.
With a good design and a well thought out plan a homeowner can create a classic and relaxing outdoor setting that they will enjoy using for years to come.
Take note of this measurement as this will be the first number in the size pergola you choose.
Patio roof maximum beam rafter spans beamsmeasuring pergola dimensions learn the standardwhat is max distance between posts using 2x12x20 foot beams for apergola beam span calculator.
In our example showing a 13 x19 big kahuna freestanding pergola this calculation would be.