DIY Gambrel Trusses for a Shed

This video is for the DIYer and covers the materials and assembly of Gambrel Style trusses for a 12' x 12'. The information can be easily scaled up or down for any size shed, barn, or house.

[@SaerTurner-wn2qh]

here is a tip for figuring out your rafter lengths ... take the span in your case 30 feet convert it to inches that is 360 inches now multiply it by the Sine of 22.5 ....360 x 0.3827= 137.772 now convert the decimal to fraction by like this 0.772 x 32 =24.704 in this case round up and you get 25/32ths of an inch so cut each rafter from long to long on 22.5 degree angles at 137 25/32ths of an inch and Presto you have perfect Gambrel roof

[@dustincarter1743]

Very good series of videos.

[@dustinnorton3541]

That top angle is also 22.5. Both angles together need to add up to 45. The lengths you have work perfect with all angles at 22.5. Just my 2 cents.

[@joleaiperlis5347]

Are the angles(22.5) the same for a 16 feet span???? I'm also doing 6 feet at peak. I am having issues figuring out the angles😅. Any input is highly appreciated.

[@jn1mrgn]

Can I assume at 1:14 that those 2x4 lengths are on the top side? Obviously if you measure on the bottom side, they will be different because of the angled cuts at the ends.

[@charliebeane5549]

Great information !
I am building a 10ft but 18ft building. What will the length of each part of the rafters be?
Thank you for any help !

[@drive8892]

Please can you help me what’s the degrees angle for a gambrel trusses for 10’x12’. The width is 10’ , length is 12’, wall is 7’, loft is 5’, total height 12’. I followed your video and I got the rafters length 3.61’ for both lower and upper. I just need the exact angle degree for each end of lower and upper rafters.

[@captcyco]

Look up “how to use speed a speed square for rafter layout” video

[@waynewazzzstonks2084]

This is not a 6ft roof

[@andrewflewelling4294]

This was very informative. Thank you. Tomorrow, I will be reinforcing rafters on a garage. I'm not sure what the dimensions are off hand and I'm not sure what gussets exist, if any, on the rafters. This is in northern Maine and there is a significant snow load. Question regarding fasteners: is there any reason not to use PL2000 and nails rather than structural screws?

[@chiefoutdoors]

greater shear strength, considerably.

[@chadsmith7793]

excellant

[@sturutherford697]

Is there a formula you use to determine the length of each board that depends on the width of the structure?

[@richardrafferty3926]

I did not use a formula. I found the exact length by establishing on a large flat surface. In my case. I used the shed floor. That had the added benefit of guaranteeing the width of the rafters would fit perfectly once the walls were up.

[@Jay-tk7ib]

You can go by a formula. Both rafters, on each side, have their own run and rise, so you'd calculate them independently, each having it's own run and rise, and therefore it's own length. This is normally for larger buildings that have walls beneath the joints of the two rafters.

[@dennisbarrientos8657]

I want to make that type of roof but i need one the is 5 ft high and 12 ft long. The angles of the rafters change??

[@richardrafferty3926]

Dennis,
You didn’t mention how wide the building will be. However, if you use the same angles the width does not matter. The only change needed is the length of the board. The simplest way I’ve found to figure out the exact length is to lay out the pattern on a large flat surface. In my case. I used the shed floor because that guaranteed the width of the rafters would fit perfectly once the walls were up.
On the other hand, if you the roof to be exactly 5’ then the angle will change some. Again, the best method is to lay out the pattern making sure the peak is at the 5’ mark.

[@dmaninthewall]

I don’t understand it how many degrees are the miters

[@gailtaylor1636]

22.5 as the diagram indicates

[@waynewazzzstonks2084]

Wasted wood

[@UncleSarkis]

How so?