This article excerpts from provides copies of roof framing suggestions from canadian building codes and the cmhc wood frame house construction guide.
Roof rafters bulginf.
My roof is the brown one at the bottom.
Framing any roof but particularly a gable roof low slope roof and cathedral ceilign roofs requires collar ties rafter ties and possibly a structural ridge beam to support the roof and to.
This roof was installed in april 2013 in northern texas.
This article describes explains the directions of forces in roof structures illustrating downwards force horizontal thrust and the causes of rafter sags rafters that disconnect from the ridge or top plate and why a sagging roof pushes the building walls outwards at the wall top.
When looking from the top it looks like this.
After a bunch of deficiencies were noted the larger roofing company fixed most of them.
Architects engineers and designers carefully calculate framing member size spacing and layout according to project specific factors.
Roof sag or roof collapse forces.
Wood rotting from the inside out compromises the structural integrity of the rafter.
Roof spread occurs when the principal rafters of the roof are not adequately supported causing them to open in a scissor like pattern.
If the ceiling joists are not properly secured they will need to be tied in to prevent further movement.
Commonly what you can see of the rotted wood is only part of the problem it is what you cannot see under the surface of the wood that can be the main issue.
We include photographs of collapsing wood framed roofs and photo sequences.
They still haven t been paid yet aside from the initial deposit.
Rotted wood rafters in a roof are a serious issue.
So i have noticed a bulge on the roof.
Something else to look for in regards to roof spread is sag.
A roof over or re roof is not recommended because it will certainly lead to buckling.
Rafters or joists are the primary supportive members of roof structures.
Sagging roof lines can originate with the horizontal ceiling rafters.
To prevent rafters from spreading bracing struts can be used to tie the rafters to the ceiling joists or a metal tie bar spanning through the building at ceiling joist level with metal plates on both sides of the wall.
The shingles are tamko 20 year 3 tab.
Therefore the first signs of roof spread are often cracking bulging or leaning at the head of the masonry causing bowed walls.
There is visible warping three years following the installation as seen in the attached images.
The roofer has recently inspected in the attic and sees no issues with framing or decking.
The nails slip out of the sheathing and create small visible bumps on the surface of your roof.
When the roof framing is assembled two ceiling rafters are often joined together to create a longer span.
He has walked the roof and says it is stable.
Buckling can occur if the wrong type of nails were used to connect the sheathing to the rafters.